Upgrade xrpl to 2.2.0 (#1443)

Fixes #1156

.clang-format

@@ -1,7 +1,7 @@
 ---
 Language:        Cpp
 AccessModifierOffset: -4
-AlignAfterOpenBracket: AlwaysBreak
+AlignAfterOpenBracket: BlockIndent
 AlignConsecutiveAssignments: false
 AlignConsecutiveDeclarations: false
 AlignEscapedNewlinesLeft: true
@@ -18,20 +18,8 @@ AlwaysBreakBeforeMultilineStrings: true
 AlwaysBreakTemplateDeclarations: true
 BinPackArguments: false
 BinPackParameters: false
-BraceWrapping:
-  AfterClass:      true
-  AfterControlStatement: true
-  AfterEnum:       false
-  AfterFunction:   true
-  AfterNamespace:  false
-  AfterObjCDeclaration: true
-  AfterStruct:     true
-  AfterUnion:      true
-  BeforeCatch:     true
-  BeforeElse:      true
-  IndentBraces:    false
 BreakBeforeBinaryOperators: false
-BreakBeforeBraces: Custom
+BreakBeforeBraces: WebKit
 BreakBeforeTernaryOperators: true
 BreakConstructorInitializersBeforeComma: true
 ColumnLimit:     120
@@ -43,13 +31,15 @@ Cpp11BracedListStyle: true
 DerivePointerAlignment: false
 DisableFormat:   false
 ExperimentalAutoDetectBinPacking: false
+FixNamespaceComments: true
 ForEachMacros:   [ Q_FOREACH,  BOOST_FOREACH ]
+IncludeBlocks: Regroup
 IncludeCategories:
-  - Regex:           '^<(BeastConfig)'
-    Priority:        0
-  - Regex:           '^<(ripple)/'
+  - Regex:           '^".*"$'
+    Priority:        1
+  - Regex:           '^<.*\.(h|hpp)>$'
     Priority:        2
-  - Regex:           '^<(boost)/'
+  - Regex:           '^<.*>$'
     Priority:        3
   - Regex:           '.*'
     Priority:        4
@@ -58,6 +48,8 @@ IndentCaseLabels: true
 IndentFunctionDeclarationAfterType: false
 IndentWidth:     4
 IndentWrappedFunctionNames: false
+IndentRequiresClause: true
+RequiresClausePosition: OwnLine
 KeepEmptyLinesAtTheStartOfBlocks: false
 MaxEmptyLinesToKeep: 1
 NamespaceIndentation: None
@@ -70,6 +62,7 @@ PenaltyBreakString: 1000
 PenaltyExcessCharacter: 1000000
 PenaltyReturnTypeOnItsOwnLine: 200
 PointerAlignment: Left
+QualifierAlignment: Right
 ReflowComments:  true
 SortIncludes:    true
 SpaceAfterCStyleCast: false

.clang-tidy

@@ -0,0 +1,133 @@
+---
+Checks: '-*,
+  bugprone-argument-comment,
+  bugprone-assert-side-effect,
+  bugprone-bad-signal-to-kill-thread,
+  bugprone-bool-pointer-implicit-conversion,
+  bugprone-copy-constructor-init,
+  bugprone-dangling-handle,
+  bugprone-dynamic-static-initializers,
+  bugprone-empty-catch,
+  bugprone-fold-init-type,
+  bugprone-forward-declaration-namespace,
+  bugprone-inaccurate-erase,
+  bugprone-incorrect-roundings,
+  bugprone-infinite-loop,
+  bugprone-integer-division,
+  bugprone-lambda-function-name,
+  bugprone-macro-parentheses,
+  bugprone-macro-repeated-side-effects,
+  bugprone-misplaced-operator-in-strlen-in-alloc,
+  bugprone-misplaced-pointer-arithmetic-in-alloc,
+  bugprone-misplaced-widening-cast,
+  bugprone-move-forwarding-reference,
+  bugprone-multiple-new-in-one-expression,
+  bugprone-multiple-statement-macro,
+  bugprone-no-escape,
+  bugprone-non-zero-enum-to-bool-conversion,
+  bugprone-parent-virtual-call,
+  bugprone-posix-return,
+  bugprone-redundant-branch-condition,
+  bugprone-reserved-identifier,
+  bugprone-unused-return-value,
+  bugprone-shared-ptr-array-mismatch,
+  bugprone-signal-handler,
+  bugprone-signed-char-misuse,
+  bugprone-sizeof-container,
+  bugprone-sizeof-expression,
+  bugprone-spuriously-wake-up-functions,
+  bugprone-standalone-empty,
+  bugprone-string-constructor,
+  bugprone-string-integer-assignment,
+  bugprone-string-literal-with-embedded-nul,
+  bugprone-stringview-nullptr,
+  bugprone-suspicious-enum-usage,
+  bugprone-suspicious-include,
+  bugprone-suspicious-memory-comparison,
+  bugprone-suspicious-memset-usage,
+  bugprone-suspicious-missing-comma,
+  bugprone-suspicious-realloc-usage,
+  bugprone-suspicious-semicolon,
+  bugprone-suspicious-string-compare,
+  bugprone-swapped-arguments,
+  bugprone-switch-missing-default-case,
+  bugprone-terminating-continue,
+  bugprone-throw-keyword-missing,
+  bugprone-too-small-loop-variable,
+  bugprone-undefined-memory-manipulation,
+  bugprone-undelegated-constructor,
+  bugprone-unhandled-exception-at-new,
+  bugprone-unhandled-self-assignment,
+  bugprone-unique-ptr-array-mismatch,
+  bugprone-unsafe-functions,
+  bugprone-unused-raii,
+  bugprone-use-after-move,
+  bugprone-virtual-near-miss,
+  cppcoreguidelines-init-variables,
+  cppcoreguidelines-misleading-capture-default-by-value,
+  cppcoreguidelines-pro-type-member-init,
+  cppcoreguidelines-pro-type-static-cast-downcast,
+  cppcoreguidelines-rvalue-reference-param-not-moved,
+  cppcoreguidelines-use-default-member-init,
+  cppcoreguidelines-virtual-class-destructor,
+  llvm-namespace-comment,
+  misc-const-correctness,
+  misc-definitions-in-headers,
+  misc-header-include-cycle,
+  misc-include-cleaner,
+  misc-misplaced-const,
+  misc-redundant-expression,
+  misc-static-assert,
+  misc-throw-by-value-catch-by-reference,
+  misc-unused-alias-decls,
+  misc-unused-using-decls,
+  modernize-concat-nested-namespaces,
+  modernize-deprecated-headers,
+  modernize-make-shared,
+  modernize-make-unique,
+  modernize-pass-by-value,
+  modernize-type-traits,
+  modernize-use-emplace,
+  modernize-use-equals-default,
+  modernize-use-equals-delete,
+  modernize-use-override,
+  modernize-use-using,
+  performance-faster-string-find,
+  performance-for-range-copy,
+  performance-implicit-conversion-in-loop,
+  performance-inefficient-vector-operation,
+  performance-move-const-arg,
+  performance-move-constructor-init,
+  performance-no-automatic-move,
+  performance-trivially-destructible,
+  readability-avoid-const-params-in-decls,
+  readability-braces-around-statements,
+  readability-const-return-type,
+  readability-container-contains,
+  readability-container-size-empty,
+  readability-convert-member-functions-to-static,
+  readability-duplicate-include,
+  readability-else-after-return,
+  readability-implicit-bool-conversion,
+  readability-inconsistent-declaration-parameter-name,
+  readability-make-member-function-const,
+  readability-misleading-indentation,
+  readability-non-const-parameter,
+  readability-redundant-declaration,
+  readability-redundant-member-init,
+  readability-redundant-string-init,
+  readability-simplify-boolean-expr,
+  readability-static-accessed-through-instance,
+  readability-static-definition-in-anonymous-namespace,
+  readability-suspicious-call-argument
+  '
+
+CheckOptions:
+  readability-braces-around-statements.ShortStatementLines: 2
+  bugprone-unsafe-functions.ReportMoreUnsafeFunctions: true
+  bugprone-unused-return-value.CheckedReturnTypes: ::std::error_code;::std::error_condition;::std::errc;::std::expected
+  misc-include-cleaner.IgnoreHeaders: '.*/(detail|impl)/.*'
+
+HeaderFilterRegex: '^.*/(src|unittests)/.*\.(h|hpp)$'
+WarningsAsErrors: '*'
+

.clangd

@@ -0,0 +1,5 @@
+Diagnostics:
+  UnusedIncludes: Strict
+  MissingIncludes: Strict
+  Includes:
+    IgnoreHeader: ".*/(detail|impl)/.*"

.codecov.yml

@@ -0,0 +1,11 @@
+coverage:
+  status:
+    project:
+      default:
+        target: 50%
+        threshold: 2%
+
+    patch:
+      default:
+        target: 20% # Need to bump this number https://docs.codecov.com/docs/commit-status#patch-status
+        threshold: 2%

.githooks/ensure_release_tag

@@ -1,20 +0,0 @@
-#!/bin/bash
-
-# Pushing a release branch requires an annotated tag at the released commit
-branch=$(git rev-parse --abbrev-ref HEAD)
-
-if [[ $branch =~ master ]]; then
-  # check if HEAD commit is tagged
-  if ! git describe --exact-match HEAD; then
-    echo "Commits to master must be tagged"
-    exit 1
-  fi
-elif [[ $branch =~ release/* ]]; then
-  IFS=/ read -r branch rel_ver <<< ${branch}
-  tag=$(git describe --tags --abbrev=0)
-  if [[ "${rel_ver}" != "${tag}" ]]; then
-    echo "release/${rel_ver} branches must have annotated tag ${rel_ver}"
-    echo "git tag -am\"${rel_ver}\" ${rel_ver}"
-    exit 1
-  fi
-fi

.githooks/pre-commit

@@ -4,10 +4,61 @@ exec 1>&2
 
 # paths to check and re-format
 sources="src unittests"
-formatter="clang-format-11 -i"
+formatter="clang-format -i"
+version=$($formatter --version | grep -o '[0-9\.]*')
+
+if [[ "17.0.0" > "$version" ]]; then
+    cat <<EOF
+
+                                    ERROR
+-----------------------------------------------------------------------------
+            A minimum of version 17 of `which clang-format` is required.
+            Your version is $version.
+            Please fix paths and run again.
+-----------------------------------------------------------------------------
+
+EOF
+    exit 3
+fi
+
+# check there is no .h headers, only .hpp
+wrong_headers=$(find $sources -name "*.h" | sed 's/^/        - /')
+if [[ ! -z "$wrong_headers" ]]; then
+    cat <<EOF
+
+                                    ERROR
+-----------------------------------------------------------------------------
+       Found .h headers in the source code. Please rename them to .hpp:
+
+$wrong_headers
+-----------------------------------------------------------------------------
+
+EOF
+    exit 2
+fi
+
+function grep_code {
+    grep -l "${1}" ${sources} -r --include \*.hpp --include \*.cpp
+}
+
+if [[ "$OSTYPE" == "darwin"* ]]; then
+    # make all includes to be <...> style
+    grep_code '#include ".*"' | xargs sed -i '' -E 's|#include "(.*)"|#include <\1>|g'
+
+    # make local includes to be "..." style
+    main_src_dirs=$(find ./src -maxdepth 1 -type d -exec basename {} \; | tr '\n' '|' | sed 's/|$//' | sed 's/|/\\|/g')
+    grep_code "#include <\($main_src_dirs\)/.*>" | xargs sed -i '' -E "s|#include <(($main_src_dirs)/.*)>|#include \"\1\"|g"
+else
+    # make all includes to be <...> style
+    grep_code '#include ".*"' | xargs sed -i -E 's|#include "(.*)"|#include <\1>|g'
+
+    # make local includes to be "..." style
+    main_src_dirs=$(find ./src -type d -maxdepth 1 -exec basename {} \; | paste -sd '|' | sed 's/|/\\|/g')
+    grep_code "#include <\($main_src_dirs\)/.*>" | xargs sed -i -E "s|#include <(($main_src_dirs)/.*)>|#include \"\1\"|g"
+fi
 
 first=$(git diff $sources)
-find $sources -type f \( -name '*.cpp' -o -name '*.h' -o -name '*.ipp' \) -print0 | xargs -0 $formatter
+find $sources -type f \( -name '*.cpp' -o -name '*.hpp' -o -name '*.ipp' \) -print0 | xargs -0 $formatter
 second=$(git diff $sources)
 changes=$(diff <(echo "$first") <(echo "$second") | wc -l | sed -e 's/^[[:space:]]*//')
 
@@ -24,4 +75,3 @@ EOF
     exit 1
 fi
 
-.githooks/ensure_release_tag

.github/actions/build_clio/action.yml

@@ -0,0 +1,18 @@
+name: Build clio
+description: Build clio in build directory
+inputs:
+  target:
+    description: Build target name
+    default: all
+runs:
+  using: composite
+  steps:
+    - name: Get number of threads
+      uses: ./.github/actions/get_number_of_threads
+      id: number_of_threads
+
+    - name: Build Clio
+      shell: bash
+      run: |
+        cd build
+        cmake --build . --parallel ${{ steps.number_of_threads.outputs.threads_number }} --target ${{ inputs.target }}

.github/actions/clang_format/action.yml

@@ -0,0 +1,36 @@
+name: Check format
+description: Check format using clang-format-17
+runs:
+  using: composite
+  steps:
+    - name: Add llvm repo
+      run: |
+        echo 'deb http://apt.llvm.org/focal/ llvm-toolchain-focal-17 main' | sudo tee -a /etc/apt/sources.list
+        wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
+      shell: bash
+
+    - name: Install packages
+      run: |
+        sudo apt update -qq
+        sudo apt install -y jq clang-format-17
+        sudo rm /usr/bin/clang-format
+        sudo ln -s /usr/bin/clang-format-17 /usr/bin/clang-format
+      shell: bash
+
+    - name: Run formatter
+      continue-on-error: true
+      id: run_formatter
+      run: |
+        ./.githooks/pre-commit
+      shell: bash
+
+    - name: Check for differences
+      id: assert
+      shell: bash
+      run: |
+        git diff --color --exit-code | tee "clang-format.patch"
+
+    - name: Fail job
+      if: ${{ steps.run_formatter.outcome != 'success' }}
+      shell: bash
+      run: exit 1

.github/actions/code_coverage/action.yml

@@ -0,0 +1,33 @@
+name: Generate code coverage report
+description: Run tests, generate code coverage report and upload it to codecov.io
+runs:
+  using: composite
+  steps:
+    - name: Run tests
+      shell: bash
+      run: |
+        build/clio_tests --backend_host=scylladb
+
+    - name: Run gcovr
+      shell: bash
+      run: |
+        gcovr -e unittests --xml build/coverage_report.xml -j8 --exclude-throw-branches
+
+    - name: Archive coverage report
+      uses: actions/upload-artifact@v3
+      with:
+        name: coverage-report.xml
+        path: build/coverage_report.xml
+        retention-days: 30
+
+    - name: Upload coverage report
+      uses: wandalen/wretry.action@v1.3.0
+      with:
+        action: codecov/codecov-action@v3
+        with: |
+          files: build/coverage_report.xml 
+          fail_ci_if_error: true
+          verbose: true
+          token: ${{ env.CODECOV_TOKEN }}
+        attempt_limit: 5
+        attempt_delay: 10000

.github/actions/generate/action.yml

@@ -0,0 +1,41 @@
+name: Run conan and cmake
+description: Run conan and cmake
+inputs:
+  conan_profile:
+    description: Conan profile name
+    required: true
+  conan_cache_hit:
+    description: Whether conan cache has been downloaded
+    required: true
+    default: 'false'
+  build_type:
+    description: Build type for third-party libraries and clio. Could be 'Release', 'Debug'
+    required: true
+    default: 'Release'
+  code_coverage:
+    description: Whether conan's coverage option should be on or not
+    required: true
+    default: 'false'
+runs:
+  using: composite
+  steps:
+    - name: Create build directory
+      shell: bash
+      run: mkdir -p build
+
+    - name: Run conan
+      shell: bash
+      env:
+        BUILD_OPTION: "${{ inputs.conan_cache_hit == 'true' && 'missing' || '' }}"
+        CODE_COVERAGE: "${{ inputs.code_coverage == 'true' && 'True' || 'False' }}"
+      run: |
+        cd build
+        conan install .. -of . -b $BUILD_OPTION -s build_type=${{ inputs.build_type }} -o clio:tests=True -o clio:lint=False -o clio:coverage="${CODE_COVERAGE}" --profile ${{ inputs.conan_profile }}
+
+    - name: Run cmake
+      shell: bash
+      env:
+        BUILD_TYPE: "${{ inputs.build_type }}"
+      run: |
+        cd build
+        cmake -DCMAKE_TOOLCHAIN_FILE:FILEPATH=build/generators/conan_toolchain.cmake -DCMAKE_BUILD_TYPE=${{ inputs.build_type }} ${{ inputs.extra_cmake_args }} .. -G Ninja

.github/actions/get_number_of_threads/action.yml

@@ -0,0 +1,26 @@
+name: Get number of threads
+description: Determines number of threads to use on macOS and Linux
+outputs:
+  threads_number:
+    description: Number of threads to use
+    value: ${{ steps.number_of_threads_export.outputs.num }}
+runs:
+  using: composite
+  steps:
+    - name: Get number of threads on mac
+      id: mac_threads
+      if: ${{ runner.os == 'macOS' }}
+      shell: bash
+      run: echo "num=$(($(sysctl -n hw.logicalcpu) - 2))" >> $GITHUB_OUTPUT
+
+    - name: Get number of threads on Linux
+      id: linux_threads
+      if: ${{ runner.os == 'Linux' }}
+      shell: bash
+      run: echo "num=$(($(nproc) - 2))" >> $GITHUB_OUTPUT
+
+    - name: Export output variable
+      shell: bash
+      id: number_of_threads_export
+      run: |
+        echo "num=${{ steps.mac_threads.outputs.num || steps.linux_threads.outputs.num }}" >> $GITHUB_OUTPUT

.github/actions/git_common_ancestor/action.yml

@@ -0,0 +1,14 @@
+name: Git common ancestor
+description: Find the closest common commit
+outputs:
+  commit:
+    description: Hash of commit
+    value: ${{ steps.find_common_ancestor.outputs.commit }}
+runs:
+  using: composite
+  steps:
+    - name: Find common git ancestor
+      id: find_common_ancestor
+      shell: bash
+      run: |
+        echo "commit=$(git merge-base --fork-point origin/develop)" >> $GITHUB_OUTPUT

.github/actions/lint/action.yml

@@ -1,13 +0,0 @@
-runs:
-  using: composite
-  steps:
-    # Github's ubuntu-20.04 image already has clang-format-11 installed
-    - run: |
-        find src unittests -type f \( -name '*.cpp' -o -name '*.h' -o -name '*.ipp' \) -print0 | xargs -0 clang-format-11 -i
-      shell: bash
-
-    - name: Check for differences
-      id: assert
-      shell: bash
-      run: |
-        git diff --color --exit-code | tee "clang-format.patch"

.github/actions/prepare_runner/action.yml

@@ -0,0 +1,47 @@
+name: Prepare runner
+description: Install packages, set environment variables, create directories
+inputs:
+  disable_ccache:
+    description: Whether ccache should be disabled
+    required: true
+runs:
+  using: composite
+  steps:
+    - name: Install packages on mac
+      if: ${{ runner.os == 'macOS' }}
+      shell: bash
+      run: |
+          brew install llvm@14 pkg-config ninja bison cmake ccache jq gh
+
+    - name: Fix git permissions on Linux
+      if: ${{ runner.os == 'Linux' }}
+      shell: bash
+      run: git config --global --add safe.directory $PWD
+
+    - name: Set env variables for macOS
+      if: ${{ runner.os == 'macOS' }}
+      shell: bash
+      run: |
+        echo "CCACHE_DIR=${{ github.workspace }}/.ccache" >> $GITHUB_ENV
+        echo "CONAN_USER_HOME=${{ github.workspace }}" >> $GITHUB_ENV
+
+    - name: Set env variables for Linux
+      if: ${{ runner.os == 'Linux' }}
+      shell: bash
+      run: |
+        echo "CCACHE_DIR=/root/.ccache" >> $GITHUB_ENV
+        echo "CONAN_USER_HOME=/root/" >> $GITHUB_ENV
+
+    - name: Set CCACHE_DISABLE=1
+      if: ${{ inputs.disable_ccache == 'true' }}
+      shell: bash
+      run: |
+        echo "CCACHE_DISABLE=1" >> $GITHUB_ENV
+
+    - name: Create directories
+      shell: bash
+      run: |
+        mkdir -p $CCACHE_DIR
+        mkdir -p $CONAN_USER_HOME/.conan
+
+

.github/actions/restore_cache/action.yml

@@ -0,0 +1,59 @@
+name: Restore cache
+description: Find and restores conan and ccache cache
+inputs:
+  conan_dir:
+    description: Path to .conan directory
+    required: true
+  ccache_dir:
+    description: Path to .ccache directory
+    required: true
+  build_type:
+    description: Current build type (e.g. Release, Debug)
+    required: true
+    default: Release
+  code_coverage:
+    description: Whether code coverage is on
+    required: true
+    default: 'false'
+outputs:
+  conan_hash:
+    description: Hash to use as a part of conan cache key
+    value: ${{ steps.conan_hash.outputs.hash }}
+  conan_cache_hit:
+    description: True if conan cache has been downloaded
+    value: ${{ steps.conan_cache.outputs.cache-hit }}
+  ccache_cache_hit:
+    description: True if ccache cache has been downloaded
+    value: ${{ steps.ccache_cache.outputs.cache-hit }}
+runs:
+  using: composite
+  steps:
+    - name: Find common commit
+      id: git_common_ancestor
+      uses: ./.github/actions/git_common_ancestor
+
+    - name: Calculate conan hash
+      id: conan_hash
+      shell: bash
+      run: |
+        conan info . -j info.json -o clio:tests=True
+        packages_info=$(cat info.json | jq '.[] | "\(.display_name): \(.id)"' | grep -v 'clio')
+        echo "$packages_info"
+        hash=$(echo "$packages_info" | shasum -a 256 | cut -d ' ' -f 1)
+        rm info.json
+        echo "hash=$hash" >> $GITHUB_OUTPUT
+
+    - name: Restore conan cache
+      uses: actions/cache/restore@v3
+      id: conan_cache
+      with:
+        path: ${{ inputs.conan_dir }}/data
+        key: clio-conan_data-${{ runner.os }}-${{ inputs.build_type }}-develop-${{ steps.conan_hash.outputs.hash }}
+
+    - name: Restore ccache cache
+      uses: actions/cache/restore@v3
+      id: ccache_cache
+      if: ${{ env.CCACHE_DISABLE != '1' }}
+      with:
+        path: ${{ inputs.ccache_dir }}
+        key: clio-ccache-${{ runner.os }}-${{ inputs.build_type }}${{ inputs.code_coverage == 'true' && '-code_coverage' || '' }}-develop-${{ steps.git_common_ancestor.outputs.commit }}

.github/actions/save_cache/action.yml

@@ -0,0 +1,56 @@
+name: Save cache
+description: Save conan and ccache cache for develop branch
+inputs:
+  conan_dir:
+    description: Path to .conan directory
+    required: true
+  conan_hash:
+    description: Hash to use as a part of conan cache key
+    required: true
+  conan_cache_hit:
+    description: Whether conan cache has been downloaded
+    required: true
+  ccache_dir:
+    description: Path to .ccache directory
+    required: true
+  ccache_cache_hit:
+    description: Whether conan cache has been downloaded
+    required: true
+  ccache_cache_miss_rate:
+    description: How many cache misses happened
+  build_type:
+    description: Current build type (e.g. Release, Debug)
+    required: true
+    default: Release
+  code_coverage:
+    description: Whether code coverage is on
+    required: true
+    default: 'false'
+runs:
+  using: composite
+  steps:
+    - name: Find common commit
+      id: git_common_ancestor
+      uses: ./.github/actions/git_common_ancestor
+
+    - name: Cleanup conan directory from extra data
+      if: ${{ inputs.conan_cache_hit != 'true' }}
+      shell: bash
+      run: |
+        conan remove "*" -s -b -f
+
+    - name: Save conan cache
+      if: ${{ inputs.conan_cache_hit != 'true' }}
+      uses: actions/cache/save@v3
+      with:
+        path: ${{ inputs.conan_dir }}/data
+        key: clio-conan_data-${{ runner.os }}-${{ inputs.build_type }}-develop-${{ inputs.conan_hash }}
+
+    - name: Save ccache cache
+      if: ${{ inputs.ccache_cache_hit != 'true' || inputs.ccache_cache_miss_rate == '100.0' }}
+      uses: actions/cache/save@v3
+      with:
+        path: ${{ inputs.ccache_dir }}
+        key: clio-ccache-${{ runner.os }}-${{ inputs.build_type }}${{ inputs.code_coverage == 'true' && '-code_coverage' || '' }}-develop-${{ steps.git_common_ancestor.outputs.commit }}
+
+

.github/actions/setup_conan/action.yml

@@ -0,0 +1,52 @@
+name: Setup conan
+description: Setup conan profile and artifactory
+outputs:
+  conan_profile:
+    description: Created conan profile name
+    value: ${{ steps.conan_export_output.outputs.conan_profile }}
+runs:
+  using: composite
+  steps:
+    - name: On mac
+      if: ${{ runner.os == 'macOS' }}
+      shell: bash
+      env:
+        CONAN_PROFILE: clio_clang_14
+      id: conan_setup_mac
+      run: |
+        echo "Creating $CONAN_PROFILE conan profile";
+        clang_path="$(brew --prefix llvm@14)/bin/clang"
+        clang_cxx_path="$(brew --prefix llvm@14)/bin/clang++"
+        conan profile new $CONAN_PROFILE --detect --force
+        conan profile update settings.compiler=clang $CONAN_PROFILE
+        conan profile update settings.compiler.version=14 $CONAN_PROFILE
+        conan profile update settings.compiler.cppstd=20 $CONAN_PROFILE
+        conan profile update "conf.tools.build:compiler_executables={\"c\": \"$clang_path\", \"cpp\": \"$clang_cxx_path\"}" $CONAN_PROFILE
+        conan profile update env.CC="$clang_path" $CONAN_PROFILE
+        conan profile update env.CXX="$clang_cxx_path" $CONAN_PROFILE
+        echo "created_conan_profile=$CONAN_PROFILE" >> $GITHUB_OUTPUT
+
+    - name: On linux
+      if: ${{ runner.os == 'Linux' }}
+      shell: bash
+      id: conan_setup_linux
+      run: |
+        echo "created_conan_profile=default" >> $GITHUB_OUTPUT
+
+    - name: Export output variable
+      shell: bash
+      id: conan_export_output
+      run: |
+        echo "conan_profile=${{ steps.conan_setup_mac.outputs.created_conan_profile || steps.conan_setup_linux.outputs.created_conan_profile }}" >> $GITHUB_OUTPUT
+
+    - name: Add conan-non-prod artifactory
+      shell: bash
+      run: |
+        if [[ -z $(conan remote list | grep conan-non-prod) ]]; then
+            echo "Adding conan-non-prod"
+            conan remote add --insert 0 conan-non-prod http://18.143.149.228:8081/artifactory/api/conan/conan-non-prod
+        else
+            echo "Conan-non-prod is available"
+        fi
+
+

.github/workflows/build.yml

@@ -1,212 +1,151 @@
-name: Build Clio
+name: Build
 on:
   push:
-    branches: [master, release/*, develop, develop-next]
+    branches: [master, release/*, develop]
   pull_request:
-    branches: [master, release/*, develop, develop-next]
+    branches: [master, release/*, develop]
   workflow_dispatch:
 
 jobs:
   lint:
-    name: Lint
+    name: Check format
     runs-on: ubuntu-20.04
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Run clang-format
-        uses: ./.github/actions/lint
+        uses: ./.github/actions/clang_format
 
-  build_clio:
-    name: Build Clio
-    runs-on: [self-hosted, heavy]
+  build:
+    name: Build
     needs: lint
     strategy:
       fail-fast: false
       matrix:
-        type:
-          - suffix: deb
-            image: rippleci/clio-dpkg-builder:2022-09-17
-            script: dpkg
-          - suffix: rpm
-            image: rippleci/clio-rpm-builder:2022-09-17
-            script: rpm
+        include:
+          - os: heavy
+            container:
+              image: rippleci/clio_ci:latest
+            build_type: Release
+            code_coverage: false
+          - os: heavy
+            container:
+              image: rippleci/clio_ci:latest
+            build_type: Debug
+            code_coverage: true
+          # - os: macOS
+          #   build_type: Release
+          #   code_coverage: false
+    runs-on: [self-hosted, "${{ matrix.os }}"]
+    container: ${{ matrix.container }}
+
+    services:
+      scylladb:
+        image: ${{ (matrix.code_coverage) && 'scylladb/scylla' || '' }}
+        options: >-
+          --health-cmd "cqlsh -e 'describe cluster'" 
+          --health-interval 10s 
+          --health-timeout 5s 
+          --health-retries 5
 
-    container:
-      image: ${{ matrix.type.image }}
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
-          path: clio
           fetch-depth: 0
 
-      - name: Clone Clio packaging repo
-        uses: actions/checkout@v3
+      - name: Prepare runner
+        uses: ./.github/actions/prepare_runner
         with:
-          path: clio-packages
-          repository: XRPLF/clio-packages
-          ref: main
+          disable_ccache: false
 
-      - name: Build
+      - name: Setup conan
+        uses: ./.github/actions/setup_conan
+        id: conan
+
+      - name: Restore cache
+        uses: ./.github/actions/restore_cache
+        id: restore_cache
+        with:
+          conan_dir: ${{ env.CONAN_USER_HOME }}/.conan
+          ccache_dir: ${{ env.CCACHE_DIR }}
+          build_type: ${{ matrix.build_type }}
+          code_coverage: ${{ matrix.code_coverage }}
+
+      - name: Run conan and cmake
+        uses: ./.github/actions/generate
+        with:
+          conan_profile: ${{ steps.conan.outputs.conan_profile }}
+          conan_cache_hit: ${{ steps.restore_cache.outputs.conan_cache_hit }}
+          build_type: ${{ matrix.build_type }}
+          code_coverage: ${{ matrix.code_coverage }}
+
+      - name: Build Clio
+        uses: ./.github/actions/build_clio
+
+      - name: Show ccache's statistics
         shell: bash
+        id: ccache_stats
         run: |
-          export CLIO_ROOT=$(realpath clio)
-          if [ ${{ matrix.type.suffix }} == "rpm" ]; then
-            source /opt/rh/devtoolset-11/enable
-          fi
-          cmake -S clio-packages -B clio-packages/build -DCLIO_ROOT=$CLIO_ROOT
-          cmake --build clio-packages/build --parallel $(nproc)
-          cp ./clio-packages/build/clio-prefix/src/clio-build/clio_tests .
-          mv ./clio-packages/build/*.${{ matrix.type.suffix }} .
-      - name: Artifact packages
+          ccache -s > /tmp/ccache.stats
+          miss_rate=$(cat /tmp/ccache.stats | grep 'Misses' | head -n1 | sed 's/.*(\(.*\)%).*/\1/')
+          echo "miss_rate=${miss_rate}" >> $GITHUB_OUTPUT
+          cat /tmp/ccache.stats
+
+      - name: Strip tests
+        if: ${{ !matrix.code_coverage }}
+        run: strip build/clio_tests
+
+      - name: Upload clio_server
         uses: actions/upload-artifact@v3
         with:
-          name: clio_${{ matrix.type.suffix }}_packages
-          path: ${{ github.workspace }}/*.${{ matrix.type.suffix }}
+          name: clio_server_${{ runner.os }}_${{ matrix.build_type }}
+          path: build/clio_server
 
-      - name: Artifact clio_tests
+      - name: Upload clio_tests
+        if: ${{ !matrix.code_coverage }}
         uses: actions/upload-artifact@v3
         with:
-          name: clio_tests-${{ matrix.type.suffix }}
-          path: ${{ github.workspace }}/clio_tests
+          name: clio_tests_${{ runner.os }}
+          path: build/clio_tests
 
-  build_dev:
-    name: Build on Mac/Clang14 and run tests
-    needs: lint
-    continue-on-error: false
-    runs-on: [self-hosted, macOS]
-
-    steps:
-      - uses: actions/checkout@v3
+      - name: Save cache
+        uses: ./.github/actions/save_cache
         with:
-          path: clio
+          conan_dir: ${{ env.CONAN_USER_HOME }}/.conan
+          conan_hash: ${{ steps.restore_cache.outputs.conan_hash }}
+          conan_cache_hit: ${{ steps.restore_cache.outputs.conan_cache_hit }}
+          ccache_dir: ${{ env.CCACHE_DIR }}
+          ccache_cache_hit: ${{ steps.restore_cache.outputs.ccache_cache_hit }}
+          ccache_cache_miss_rate: ${{ steps.ccache_stats.outputs.miss_rate }}
+          build_type: ${{ matrix.build_type }}
+          code_coverage: ${{ matrix.code_coverage }}
 
-      - name: Check Boost cache
-        id: boost
-        uses: actions/cache@v3
-        with:
-          path: boost_1_77_0
-          key: ${{ runner.os }}-boost
+      # TODO: This is not a part of build process but it is the easiest way to do it here.
+      # It will be refactored in https://github.com/XRPLF/clio/issues/1075
+      - name: Run code coverage
+        if: ${{ matrix.code_coverage }}
+        env:
+          CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
+        uses: ./.github/actions/code_coverage
 
-      - name: Build Boost
-        if: ${{ steps.boost.outputs.cache-hit != 'true' }}
-        run: |
-          rm -rf boost_1_77_0.tar.gz boost_1_77_0 # cleanup if needed first
-          curl -s -fOJL "https://boostorg.jfrog.io/artifactory/main/release/1.77.0/source/boost_1_77_0.tar.gz"
-          tar zxf boost_1_77_0.tar.gz
-          cd boost_1_77_0
-          ./bootstrap.sh
-          ./b2 define=BOOST_ASIO_HAS_STD_INVOKE_RESULT cxxflags="-std=c++20"
-
-      - name: Install dependencies
-        run: |
-          brew install llvm@14 pkg-config protobuf openssl ninja cassandra-cpp-driver bison cmake
-
-      - name: Setup environment for llvm-14
-        run: |
-          export PATH="/usr/local/opt/llvm@14/bin:$PATH"
-          export LDFLAGS="-L/usr/local/opt/llvm@14/lib -L/usr/local/opt/llvm@14/lib/c++ -Wl,-rpath,/usr/local/opt/llvm@14/lib/c++"
-          export CPPFLAGS="-I/usr/local/opt/llvm@14/include"
-
-      - name: Build clio
-        run: |
-          export BOOST_ROOT=$(pwd)/boost_1_77_0
-          cd clio
-          cmake -B build -DCMAKE_C_COMPILER='/usr/local/opt/llvm@14/bin/clang' -DCMAKE_CXX_COMPILER='/usr/local/opt/llvm@14/bin/clang++'
-          if ! cmake --build build -j; then
-            echo '# 🔥🔥 MacOS AppleClang build failed!💥' >> $GITHUB_STEP_SUMMARY
-            exit 1
-          fi
-      - name: Run Test
-        run: |
-          cd clio/build
-          ./clio_tests --gtest_filter="-BackendTest*:BackendCassandraBaseTest*:BackendCassandraTest*"
-
-  test_clio:
-    name: Test Clio
-    runs-on: [self-hosted, Linux]
-    needs: build_clio
+  test:
+    name: Run Tests
+    needs: build
     strategy:
       fail-fast: false
       matrix:
-        suffix: [rpm, deb]
-    steps:
-      - uses: actions/checkout@v3
-
-      - name: Get clio_tests artifact
-        uses: actions/download-artifact@v3
-        with:
-          name: clio_tests-${{ matrix.suffix }}
-
-      - name: Run tests
-        timeout-minutes: 10
-        uses: ./.github/actions/test
-
-  code_coverage:
-    name: Build on Linux and code coverage
-    needs: lint
-    continue-on-error: false
-    runs-on: ubuntu-22.04
+        include:
+          - os: heavy
+            container:
+              image: rippleci/clio_ci:latest
+          # - os: macOS
+    runs-on: [self-hosted, "${{ matrix.os }}"]
+    container: ${{ matrix.container }}
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/download-artifact@v3
         with:
-          path: clio
-
-      - name: Check Boost cache
-        id: boost
-        uses: actions/cache@v3
-        with:
-          path: boost
-          key: ${{ runner.os }}-boost
-
-      - name: Build boost
-        if: steps.boost.outputs.cache-hit != 'true'
+          name: clio_tests_${{ runner.os }}
+      - name: Run clio_tests
         run: |
-          curl -s -OJL "https://boostorg.jfrog.io/artifactory/main/release/1.77.0/source/boost_1_77_0.tar.gz"
-          tar zxf boost_1_77_0.tar.gz
-          mv boost_1_77_0 boost
-          cd boost
-          ./bootstrap.sh
-          ./b2
-      - name: install deps
-        run: |
-          sudo apt-get -y install git pkg-config protobuf-compiler libprotobuf-dev libssl-dev wget build-essential doxygen bison flex autoconf clang-format gcovr
-      - name: Build clio
-        run: |
-          export BOOST_ROOT=$(pwd)/boost
-          cd clio
-          cmake -B build -DCODE_COVERAGE=on -DTEST_PARAMETER='--gtest_filter="-BackendTest*:BackendCassandraBaseTest*:BackendCassandraTest*"'
-          if ! cmake --build build -j$(nproc); then
-            echo '# 🔥Ubuntu build🔥 failed!💥' >> $GITHUB_STEP_SUMMARY
-            exit 1
-          fi
-          cd build
-          make clio_tests-ccov
-      - name: Code Coverage Summary Report
-        uses: irongut/CodeCoverageSummary@v1.2.0
-        with:
-          filename: clio/build/clio_tests-gcc-cov/out.xml
-          badge: true
-          output: both
-          format: markdown
-
-      - name: Save PR number and ccov report
-        run: |
-          mkdir -p ./UnitTestCoverage
-          echo ${{ github.event.number }} > ./UnitTestCoverage/NR
-          cp clio/build/clio_tests-gcc-cov/report.html ./UnitTestCoverage/report.html
-          cp code-coverage-results.md ./UnitTestCoverage/out.md
-          cat code-coverage-results.md > $GITHUB_STEP_SUMMARY
-      - name: Upload coverage reports to Codecov
-        uses: codecov/codecov-action@v3
-        with:
-          files: clio/build/clio_tests-gcc-cov/out.xml
-
-      - uses: actions/upload-artifact@v3
-        with:
-          name: UnitTestCoverage
-          path: UnitTestCoverage/
-
-      - uses: actions/upload-artifact@v3
-        with:
-          name: code_coverage_report
-          path: clio/build/clio_tests-gcc-cov/out.xml
+          chmod +x ./clio_tests
+          ./clio_tests --gtest_filter="-BackendCassandraBaseTest*:BackendCassandraTest*:BackendCassandraFactoryTestWithDB*"

.github/workflows/clang-tidy.yml

@@ -0,0 +1,116 @@
+name: Clang-tidy check
+on:
+  schedule:
+    - cron: "0 6 * * 1-5"
+  workflow_dispatch:
+  pull_request:
+    branches: [develop]
+    paths:
+      - .clang_tidy
+      - .github/workflows/clang-tidy.yml
+  workflow_call:
+
+jobs:
+  clang_tidy:
+    runs-on: [self-hosted, Linux]
+    container:
+      image: rippleci/clio_ci:latest
+    permissions:
+      contents: write
+      issues: write
+      pull-requests: write
+
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Prepare runner
+        uses: ./.github/actions/prepare_runner
+        with:
+          disable_ccache: true
+
+      - name: Setup conan
+        uses: ./.github/actions/setup_conan
+        id: conan
+
+      - name: Restore cache
+        uses: ./.github/actions/restore_cache
+        id: restore_cache
+        with:
+          conan_dir: ${{ env.CONAN_USER_HOME }}/.conan
+          ccache_dir: ${{ env.CCACHE_DIR }}
+
+      - name: Run conan and cmake
+        uses: ./.github/actions/generate
+        with:
+          conan_profile: ${{ steps.conan.outputs.conan_profile }}
+          conan_cache_hit: ${{ steps.restore_cache.outputs.conan_cache_hit }}
+          build_type: Release
+
+      - name: Get number of threads
+        uses: ./.github/actions/get_number_of_threads
+        id: number_of_threads
+
+      - name: Run clang-tidy
+        continue-on-error: true
+        shell: bash
+        id: run_clang_tidy
+        run: |
+          run-clang-tidy-17 -p build -j ${{ steps.number_of_threads.outputs.threads_number }} -fix -quiet 1>output.txt
+
+      - name: Run pre-commit hook
+        if: ${{ steps.run_clang_tidy.outcome != 'success' }}
+        continue-on-error: true
+        shell: bash
+        run: ./.githooks/pre-commit
+
+      - name: Print issues found
+        if: ${{ steps.run_clang_tidy.outcome != 'success' }}
+        shell: bash
+        run: |
+          sed -i '/error\||/!d' ./output.txt
+          cat output.txt
+          rm output.txt
+
+      - name: Create an issue
+        if: ${{ steps.run_clang_tidy.outcome != 'success' }}
+        id: create_issue
+        shell: bash
+        env:
+          GH_TOKEN: ${{ github.token }}
+        run: |
+          echo -e 'Clang-tidy found issues in the code:\n' > issue.md
+          echo -e "List of the issues found: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}/" >> issue.md
+          gh issue create --assignee 'cindyyan317,godexsoft,kuznetsss' --label bug --title 'Clang-tidy found bugs in code🐛' --body-file ./issue.md > create_issue.log
+          created_issue=$(cat create_issue.log | sed 's|.*/||')
+          echo "created_issue=$created_issue" >> $GITHUB_OUTPUT
+          rm create_issue.log issue.md
+
+      - uses: crazy-max/ghaction-import-gpg@v5
+        with:
+          gpg_private_key: ${{ secrets.ACTIONS_GPG_PRIVATE_KEY }}
+          passphrase: ${{ secrets.ACTIONS_GPG_PASSPHRASE }}
+          git_user_signingkey: true
+          git_commit_gpgsign: true
+
+      - name: Create PR with fixes
+        if: ${{ steps.run_clang_tidy.outcome != 'success' }}
+        uses: peter-evans/create-pull-request@v5
+        env:
+          GH_REPO: ${{ github.repository }}
+          GH_TOKEN: ${{ github.token }}
+        with:
+          commit-message: "[CI] clang-tidy auto fixes"
+          committer: Clio CI <skuznetsov@ripple.com>
+          branch: "clang_tidy/autofix"
+          branch-suffix: timestamp
+          delete-branch: true
+          title: "[CI] clang-tidy auto fixes"
+          body: "Fixes #${{ steps.create_issue.outputs.created_issue }}. Please review and commit clang-tidy fixes."
+          reviewers: "cindyyan317,godexsoft,kuznetsss"
+
+      - name: Fail the job
+        if: ${{ steps.run_clang_tidy.outcome != 'success' }}
+        shell: bash
+        run: exit 1

.github/workflows/clang-tidy_on_fix_merged.yml

@@ -0,0 +1,29 @@
+name: Restart clang-tidy workflow
+on:
+  push:
+    branches: [develop]
+  workflow_dispatch:
+
+jobs:
+  restart_clang_tidy:
+    runs-on: ubuntu-20.04
+
+    permissions:
+      actions: write
+
+    steps:
+      - uses: actions/checkout@v4
+      - name: Check last commit matches clang-tidy auto fixes
+        id: check
+        shell: bash
+        run: |
+          passed=$(if [[ $(git log -1 --pretty=format:%s | grep '\[CI\] clang-tidy auto fixes') ]]; then echo 'true' ; else echo 'false' ; fi)
+          echo "passed=$passed" >> $GITHUB_OUTPUT
+
+      - name: Run clang-tidy workflow
+        if: ${{ contains(steps.check.outputs.passed, 'true') }}
+        shell: bash
+        env:
+          GH_TOKEN: ${{ github.token }}
+          GH_REPO: ${{ github.repository }}
+        run: gh workflow run clang-tidy.yml

.github/workflows/nightly.yml

@@ -0,0 +1,138 @@
+name: Nightly release
+on:
+  schedule:
+    - cron:  '0 5 * * 1-5'
+  workflow_dispatch:
+
+jobs:
+  build:
+    name: Build clio
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          # - os: macOS
+          #   build_type: Release
+          - os: heavy
+            build_type: Release
+            container:
+              image: rippleci/clio_ci:latest
+          - os: heavy
+            build_type: Debug
+            container:
+              image: rippleci/clio_ci:latest
+    runs-on: [self-hosted, "${{ matrix.os }}"]
+    container: ${{ matrix.container }}
+
+    steps:
+      - uses: actions/checkout@v4
+        with:
+            fetch-depth: 0
+
+      - name: Prepare runner
+        uses: ./.github/actions/prepare_runner
+        with:
+            disable_ccache: true
+
+      - name: Setup conan
+        uses: ./.github/actions/setup_conan
+        id: conan
+
+      - name: Run conan and cmake
+        uses: ./.github/actions/generate
+        with:
+          conan_profile: ${{ steps.conan.outputs.conan_profile }}
+          conan_cache_hit: ${{ steps.restore_cache.outputs.conan_cache_hit }}
+          build_type: ${{ matrix.build_type }}
+
+      - name: Build Clio
+        uses: ./.github/actions/build_clio
+
+      - name: Strip tests
+        run: strip build/clio_tests
+
+      - name: Upload clio_tests
+        uses: actions/upload-artifact@v3
+        with:
+          name: clio_tests_${{ runner.os }}_${{ matrix.build_type }}
+          path: build/clio_tests
+
+      - name: Compress clio_server
+        shell: bash
+        run: |
+            cd build
+            tar czf ./clio_server_${{ runner.os }}_${{ matrix.build_type }}.tar.gz ./clio_server
+
+      - name: Upload clio_server
+        uses: actions/upload-artifact@v3
+        with:
+          name: clio_server_${{ runner.os }}_${{ matrix.build_type }}
+          path: build/clio_server_${{ runner.os }}_${{ matrix.build_type }}.tar.gz
+
+
+  run_tests:
+    needs: build
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          # - os: macOS
+          #   build_type: Release
+          - os: heavy
+            build_type: Release
+          - os: heavy
+            build_type: Debug
+    runs-on: [self-hosted, "${{ matrix.os }}"]
+
+    steps:
+      - uses: actions/download-artifact@v3
+        with:
+          name: clio_tests_${{ runner.os }}_${{ matrix.build_type }}
+
+      - name: Run clio_tests
+        run: |
+          chmod +x ./clio_tests
+          ./clio_tests --gtest_filter="-BackendCassandraBaseTest*:BackendCassandraTest*:BackendCassandraFactoryTestWithDB*"
+
+  nightly_release:
+    needs: run_tests
+    runs-on: ubuntu-20.04
+    env:
+      GH_REPO: ${{ github.repository }}
+      GH_TOKEN: ${{ github.token }}
+    permissions:
+      contents: write
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/download-artifact@v3
+        with:
+          path: nightly_release
+
+      - name: Prepare files
+        shell: bash
+        run: |
+          cp ${{ github.workspace }}/.github/workflows/nightly_notes.md "${RUNNER_TEMP}/nightly_notes.md"
+          cd nightly_release
+          rm -r clio_tests*
+          for d in $(ls); do
+            archive_name=$(ls $d)
+            mv ${d}/${archive_name} ./
+            rm -r $d
+            sha256sum ./$archive_name > ./${archive_name}.sha256sum
+            cat ./$archive_name.sha256sum >> "${RUNNER_TEMP}/nightly_notes.md"
+          done
+          echo '```' >> "${RUNNER_TEMP}/nightly_notes.md"
+
+      - name: Remove current nightly release and nightly tag
+        shell: bash
+        run: |
+          gh release delete nightly --yes || true
+          git push origin :nightly || true
+
+      - name: Publish nightly release
+        shell: bash
+        run: |
+          gh release create nightly --prerelease --title "Clio development (nightly) build" \
+            --target $GITHUB_SHA --notes-file "${RUNNER_TEMP}/nightly_notes.md" \
+            ./nightly_release/clio_server*

.github/workflows/nightly_notes.md

@@ -0,0 +1,6 @@
+> **Note:** Please remember that this is a development release and it is not recommended for production use.
+
+Changelog (including previous releases): https://github.com/XRPLF/clio/commits/nightly
+
+## SHA256 checksums
+```

.github/workflows/update_docker_ci.yml

@@ -0,0 +1,40 @@
+name: Update CI docker image
+on:
+  push:
+    branches: [develop]
+    paths:
+      - 'docker/ci/**'
+      - .github/workflows/update_docker_ci.yml
+  workflow_dispatch:
+
+jobs:
+  build_and_push:
+    name: Build and push docker image
+    runs-on: ubuntu-20.04
+    steps:
+      - name: Login to DockerHub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.DOCKERHUB_USER }}
+          password: ${{ secrets.DOCKERHUB_PW }}
+
+      - uses: actions/checkout@v4
+      - uses: docker/setup-qemu-action@v3
+      - uses: docker/setup-buildx-action@v3
+      - uses: docker/metadata-action@v5
+        id: meta
+        with:
+          images: rippleci/clio_ci
+          tags: |
+            type=raw,value=latest
+            type=raw,value=gcc_11
+            type=raw,value=${{ env.GITHUB_SHA }}
+
+      - name: Build and push
+        uses: docker/build-push-action@v5
+        with:
+          context: ${{ github.workspace }}/docker/ci
+          platforms: linux/amd64,linux/arm64
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+

.gitignore

@@ -1,6 +1,10 @@
 *clio*.log
-build*/
+/build*/
+.devcontainer
+.build
+.cache
 .vscode
 .python-version
+CMakeUserPresets.json
 config.json
 src/main/impl/Build.cpp

CMake/Build.cpp.in

@@ -17,7 +17,9 @@
 */
 //==============================================================================
 
-#include <main/Build.h>
+#include "main/Build.hpp"
+
+#include <string>
 
 namespace Build {
 static constexpr char versionString[] = "@VERSION@";

CMake/Ccache.cmake

@@ -0,0 +1,5 @@
+find_program (CCACHE_PATH "ccache")
+if (CCACHE_PATH)
+    set (CMAKE_CXX_COMPILER_LAUNCHER "${CCACHE_PATH}")
+    message (STATUS "Using ccache: ${CCACHE_PATH}")
+endif ()

CMake/CheckCompiler.cmake

@@ -0,0 +1,42 @@
+if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
+  if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 14)
+    message (FATAL_ERROR "Clang 14+ required for building clio")
+  endif ()
+  set (is_clang TRUE)
+elseif (CMAKE_CXX_COMPILER_ID STREQUAL "AppleClang")
+  if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 14)
+    message (FATAL_ERROR "AppleClang 14+ required for building clio")
+  endif ()
+  set (is_appleclang TRUE)
+elseif (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
+  if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 11)
+    message (FATAL_ERROR "GCC 11+ required for building clio")
+  endif ()
+  set (is_gcc TRUE)
+else ()
+  message (FATAL_ERROR "Supported compilers: AppleClang 14+, Clang 14+, GCC 11+")
+endif ()
+
+if (san)
+  string (TOLOWER ${san} san)
+  set (SAN_FLAG "-fsanitize=${san}")
+  set (SAN_LIB "")
+  if (is_gcc)
+    if (san STREQUAL "address")
+      set (SAN_LIB "asan")
+    elseif (san STREQUAL "thread")
+      set (SAN_LIB "tsan")
+    elseif (san STREQUAL "memory")
+      set (SAN_LIB "msan")
+    elseif (san STREQUAL "undefined")
+      set (SAN_LIB "ubsan")
+    endif ()
+  endif ()
+  set (_saved_CRL ${CMAKE_REQUIRED_LIBRARIES})
+  set (CMAKE_REQUIRED_LIBRARIES "${SAN_FLAG};${SAN_LIB}")
+  CHECK_CXX_COMPILER_FLAG (${SAN_FLAG} COMPILER_SUPPORTS_SAN)
+  set (CMAKE_REQUIRED_LIBRARIES ${_saved_CRL})
+  if (NOT COMPILER_SUPPORTS_SAN)
+    message (FATAL_ERROR "${san} sanitizer does not seem to be supported by your compiler")
+  endif ()
+endif ()

CMake/ClangTidy.cmake

@@ -0,0 +1,31 @@
+if (lint)
+
+  # Find clang-tidy binary
+  if (DEFINED ENV{CLIO_CLANG_TIDY_BIN})
+    set (_CLANG_TIDY_BIN $ENV{CLIO_CLANG_TIDY_BIN})
+    if ((NOT EXISTS ${_CLANG_TIDY_BIN}) OR IS_DIRECTORY ${_CLANG_TIDY_BIN})
+      message (FATAL_ERROR "$ENV{CLIO_CLANG_TIDY_BIN} no such file. Check CLIO_CLANG_TIDY_BIN env variable")
+    endif ()
+    message (STATUS "Using clang-tidy from CLIO_CLANG_TIDY_BIN")
+  else ()
+    find_program (_CLANG_TIDY_BIN NAMES "clang-tidy-17" "clang-tidy" REQUIRED)
+  endif ()
+
+  if (NOT _CLANG_TIDY_BIN)
+    message (FATAL_ERROR
+      "clang-tidy binary not found. Please set the CLIO_CLANG_TIDY_BIN environment variable or install clang-tidy.")
+  endif ()
+
+  # Support for https://github.com/matus-chochlik/ctcache
+  find_program (CLANG_TIDY_CACHE_PATH NAMES "clang-tidy-cache")
+  if (CLANG_TIDY_CACHE_PATH)
+    set (_CLANG_TIDY_CMD
+        "${CLANG_TIDY_CACHE_PATH};${_CLANG_TIDY_BIN}"
+        CACHE STRING "A combined command to run clang-tidy with caching wrapper")
+  else ()
+    set(_CLANG_TIDY_CMD "${_CLANG_TIDY_BIN}")
+  endif ()
+
+  set (CMAKE_CXX_CLANG_TIDY "${_CLANG_TIDY_CMD};--quiet")
+  message (STATUS "Using clang-tidy: ${CMAKE_CXX_CLANG_TIDY}")
+endif ()

CMake/ClioVersion.cmake

@@ -2,32 +2,38 @@
    write version to source
 #]===================================================================]
 
-find_package(Git REQUIRED)
+find_package (Git REQUIRED)
 
-set(GIT_COMMAND rev-parse --short HEAD)
-execute_process(COMMAND ${GIT_EXECUTABLE} ${GIT_COMMAND} OUTPUT_VARIABLE REV OUTPUT_STRIP_TRAILING_WHITESPACE)
+set (GIT_COMMAND rev-parse --short HEAD)
+execute_process (COMMAND ${GIT_EXECUTABLE} ${GIT_COMMAND} 
+  WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}
+  OUTPUT_VARIABLE REV OUTPUT_STRIP_TRAILING_WHITESPACE)
 
-set(GIT_COMMAND branch --show-current)
-execute_process(COMMAND ${GIT_EXECUTABLE} ${GIT_COMMAND} OUTPUT_VARIABLE BRANCH OUTPUT_STRIP_TRAILING_WHITESPACE)
+set (GIT_COMMAND branch --show-current)
+execute_process (COMMAND ${GIT_EXECUTABLE} ${GIT_COMMAND} 
+  WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}
+  OUTPUT_VARIABLE BRANCH OUTPUT_STRIP_TRAILING_WHITESPACE)
 
-if(BRANCH STREQUAL "")
-  set(BRANCH "dev")
-endif()
+if (BRANCH STREQUAL "")
+  set (BRANCH "dev")
+endif ()
 
-if(NOT (BRANCH MATCHES master OR BRANCH MATCHES release/*)) # for develop and any other branch name YYYYMMDDHMS-<branch>-<git-ref>
-  execute_process(COMMAND date +%Y%m%d%H%M%S OUTPUT_VARIABLE DATE OUTPUT_STRIP_TRAILING_WHITESPACE)
-  set(VERSION "${DATE}-${BRANCH}-${REV}")
-else()
-  set(GIT_COMMAND describe --tags)
-  execute_process(COMMAND ${GIT_EXECUTABLE} ${GIT_COMMAND} OUTPUT_VARIABLE TAG_VERSION OUTPUT_STRIP_TRAILING_WHITESPACE)
-  set(VERSION "${TAG_VERSION}-${REV}")
-endif()
+if (NOT (BRANCH MATCHES master OR BRANCH MATCHES release/*)) # for develop and any other branch name YYYYMMDDHMS-<branch>-<git-rev>
+  execute_process (COMMAND date +%Y%m%d%H%M%S OUTPUT_VARIABLE DATE OUTPUT_STRIP_TRAILING_WHITESPACE)
+  set (VERSION "${DATE}-${BRANCH}-${REV}")
+else ()
+  set (GIT_COMMAND describe --tags)
+  execute_process (COMMAND ${GIT_EXECUTABLE} ${GIT_COMMAND} 
+    WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}
+    OUTPUT_VARIABLE TAG_VERSION OUTPUT_STRIP_TRAILING_WHITESPACE)
+  set (VERSION "${TAG_VERSION}-${REV}")
+endif ()
 
-if(CMAKE_BUILD_TYPE MATCHES Debug)
-  set(VERSION "${VERSION}+DEBUG")
-endif()
+if (CMAKE_BUILD_TYPE MATCHES Debug)
+  set (VERSION "${VERSION}+DEBUG")
+endif ()
 
-message(STATUS "Build version: ${VERSION}")
-set(clio_version "${VERSION}")
+message (STATUS "Build version: ${VERSION}")
+set (clio_version "${VERSION}")
 
-configure_file(CMake/Build.cpp.in ${CMAKE_SOURCE_DIR}/src/main/impl/Build.cpp)
+configure_file (CMake/Build.cpp.in ${CMAKE_SOURCE_DIR}/src/main/impl/Build.cpp)

CMake/CodeCoverage.cmake

@@ -0,0 +1,440 @@
+# Copyright (c) 2012 - 2017, Lars Bilke
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without modification,
+# are permitted provided that the following conditions are met:
+#
+# 1. Redistributions of source code must retain the above copyright notice, this
+#    list of conditions and the following disclaimer.
+#
+# 2. Redistributions in binary form must reproduce the above copyright notice,
+#    this list of conditions and the following disclaimer in the documentation
+#    and/or other materials provided with the distribution.
+#
+# 3. Neither the name of the copyright holder nor the names of its contributors
+#    may be used to endorse or promote products derived from this software without
+#    specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+# ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+# ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# CHANGES:
+#
+# 2012-01-31, Lars Bilke
+# - Enable Code Coverage
+#
+# 2013-09-17, Joakim Söderberg
+# - Added support for Clang.
+# - Some additional usage instructions.
+#
+# 2016-02-03, Lars Bilke
+# - Refactored functions to use named parameters
+#
+# 2017-06-02, Lars Bilke
+# - Merged with modified version from github.com/ufz/ogs
+#
+# 2019-05-06, Anatolii Kurotych
+# - Remove unnecessary --coverage flag
+#
+# 2019-12-13, FeRD (Frank Dana)
+# - Deprecate COVERAGE_LCOVR_EXCLUDES and COVERAGE_GCOVR_EXCLUDES lists in favor
+#   of tool-agnostic COVERAGE_EXCLUDES variable, or EXCLUDE setup arguments.
+# - CMake 3.4+: All excludes can be specified relative to BASE_DIRECTORY
+# - All setup functions: accept BASE_DIRECTORY, EXCLUDE list
+# - Set lcov basedir with -b argument
+# - Add automatic --demangle-cpp in lcovr, if 'c++filt' is available (can be
+#   overridden with NO_DEMANGLE option in setup_target_for_coverage_lcovr().)
+# - Delete output dir, .info file on 'make clean'
+# - Remove Python detection, since version mismatches will break gcovr
+# - Minor cleanup (lowercase function names, update examples...)
+#
+# 2019-12-19, FeRD (Frank Dana)
+# - Rename Lcov outputs, make filtered file canonical, fix cleanup for targets
+#
+# 2020-01-19, Bob Apthorpe
+# - Added gfortran support
+#
+# 2020-02-17, FeRD (Frank Dana)
+# - Make all add_custom_target()s VERBATIM to auto-escape wildcard characters
+#   in EXCLUDEs, and remove manual escaping from gcovr targets
+#
+# 2021-01-19, Robin Mueller
+# - Add CODE_COVERAGE_VERBOSE option which will allow to print out commands which are run
+# - Added the option for users to set the GCOVR_ADDITIONAL_ARGS variable to supply additional
+#   flags to the gcovr command
+#
+# 2020-05-04, Mihchael Davis
+#     - Add -fprofile-abs-path to make gcno files contain absolute paths
+#     - Fix BASE_DIRECTORY not working when defined
+#     - Change BYPRODUCT from folder to index.html to stop ninja from complaining about double defines
+#
+# 2021-05-10, Martin Stump
+#     - Check if the generator is multi-config before warning about non-Debug builds
+#
+# 2022-02-22, Marko Wehle
+#     - Change gcovr output from -o <filename> for --xml <filename> and --html <filename> output respectively.
+#       This will allow for Multiple Output Formats at the same time by making use of GCOVR_ADDITIONAL_ARGS, e.g. GCOVR_ADDITIONAL_ARGS "--txt".
+#
+# 2022-09-28, Sebastian Mueller
+#     - fix append_coverage_compiler_flags_to_target to correctly add flags
+#     - replace "-fprofile-arcs -ftest-coverage" with "--coverage" (equivalent)
+#
+# 2023-12-15, Bronek Kozicki
+#     - remove setup_target_for_coverage_lcov (slow) and setup_target_for_coverage_fastcov (no support for Clang)
+#     - fix Clang support by adding find_program( ... llvm-cov )
+#     - add Apple Clang support by adding execute_process( COMMAND xcrun -f llvm-cov ... )
+#     - add CODE_COVERAGE_GCOV_TOOL to explicitly select gcov tool and disable find_program
+#     - replace both functions setup_target_for_coverage_gcovr_* with single setup_target_for_coverage_gcovr
+#     - add support for all gcovr output formats
+#
+# USAGE:
+#
+# 1. Copy this file into your cmake modules path.
+#
+# 2. Add the following line to your CMakeLists.txt (best inside an if-condition
+#    using a CMake option() to enable it just optionally):
+#      include(CodeCoverage)
+#
+# 3. Append necessary compiler flags for all supported source files:
+#      append_coverage_compiler_flags()
+#    Or for specific target:
+#      append_coverage_compiler_flags_to_target(YOUR_TARGET_NAME)
+#
+# 3.a (OPTIONAL) Set appropriate optimization flags, e.g. -O0, -O1 or -Og
+#
+# 4. If you need to exclude additional directories from the report, specify them
+#    using full paths in the COVERAGE_EXCLUDES variable before calling
+#    setup_target_for_coverage_*().
+#    Example:
+#      set(COVERAGE_EXCLUDES
+#          '${PROJECT_SOURCE_DIR}/src/dir1/*'
+#          '/path/to/my/src/dir2/*')
+#    Or, use the EXCLUDE argument to setup_target_for_coverage_*().
+#    Example:
+#      setup_target_for_coverage_gcovr(
+#          NAME coverage
+#          EXECUTABLE testrunner
+#          EXCLUDE "${PROJECT_SOURCE_DIR}/src/dir1/*" "/path/to/my/src/dir2/*")
+#
+# 4.a NOTE: With CMake 3.4+, COVERAGE_EXCLUDES or EXCLUDE can also be set
+#     relative to the BASE_DIRECTORY (default: PROJECT_SOURCE_DIR)
+#     Example:
+#       set(COVERAGE_EXCLUDES "dir1/*")
+#       setup_target_for_coverage_gcovr(
+#           NAME coverage
+#           EXECUTABLE testrunner
+#           FORMAT html-details
+#           BASE_DIRECTORY "${PROJECT_SOURCE_DIR}/src"
+#           EXCLUDE "dir2/*")
+#
+# 4.b If you need to pass specific options to gcovr, specify them in
+#     GCOVR_ADDITIONAL_ARGS variable.
+#     Example:
+#       set (GCOVR_ADDITIONAL_ARGS --exclude-throw-branches --exclude-noncode-lines -s)
+#       setup_target_for_coverage_gcovr(
+#           NAME coverage
+#           EXECUTABLE testrunner
+#           EXCLUDE "src/dir1" "src/dir2")
+#
+# 5. Use the functions described below to create a custom make target which
+#    runs your test executable and produces a code coverage report.
+#
+# 6. Build a Debug build:
+#      cmake -DCMAKE_BUILD_TYPE=Debug ..
+#      make
+#      make my_coverage_target
+
+include(CMakeParseArguments)
+
+option(CODE_COVERAGE_VERBOSE "Verbose information" FALSE)
+
+# Check prereqs
+find_program( GCOVR_PATH gcovr PATHS ${CMAKE_SOURCE_DIR}/scripts/test)
+
+if (DEFINED CODE_COVERAGE_GCOV_TOOL)
+  set(GCOV_TOOL "${CODE_COVERAGE_GCOV_TOOL}")
+elseif (DEFINED ENV{CODE_COVERAGE_GCOV_TOOL})
+  set(GCOV_TOOL "$ENV{CODE_COVERAGE_GCOV_TOOL}")
+elseif("${CMAKE_CXX_COMPILER_ID}" MATCHES "(Apple)?[Cc]lang")
+  if (APPLE)
+    execute_process( COMMAND xcrun -f llvm-cov
+      OUTPUT_VARIABLE LLVMCOV_PATH
+      OUTPUT_STRIP_TRAILING_WHITESPACE
+    )
+  else()
+    find_program( LLVMCOV_PATH llvm-cov )
+  endif()
+  if(LLVMCOV_PATH)
+    set(GCOV_TOOL "${LLVMCOV_PATH} gcov")
+  endif()
+elseif ("${CMAKE_CXX_COMPILER_ID}" MATCHES "GNU")
+  find_program( GCOV_PATH gcov )
+  set(GCOV_TOOL "${GCOV_PATH}")
+endif()
+
+# Check supported compiler (Clang, GNU and Flang)
+get_property(LANGUAGES GLOBAL PROPERTY ENABLED_LANGUAGES)
+foreach(LANG ${LANGUAGES})
+  if("${CMAKE_${LANG}_COMPILER_ID}" MATCHES "(Apple)?[Cc]lang")
+    if("${CMAKE_${LANG}_COMPILER_VERSION}" VERSION_LESS 3)
+      message(FATAL_ERROR "Clang version must be 3.0.0 or greater! Aborting...")
+    endif()
+  elseif(NOT "${CMAKE_${LANG}_COMPILER_ID}" MATCHES "GNU"
+         AND NOT "${CMAKE_${LANG}_COMPILER_ID}" MATCHES "(LLVM)?[Ff]lang")
+    message(FATAL_ERROR "Compiler is not GNU or Flang! Aborting...")
+  endif()
+endforeach()
+
+set(COVERAGE_COMPILER_FLAGS "-g --coverage"
+    CACHE INTERNAL "")
+if(CMAKE_CXX_COMPILER_ID MATCHES "(GNU|Clang)")
+    include(CheckCXXCompilerFlag)
+    check_cxx_compiler_flag(-fprofile-abs-path HAVE_cxx_fprofile_abs_path)
+    if(HAVE_cxx_fprofile_abs_path)
+        set(COVERAGE_CXX_COMPILER_FLAGS "${COVERAGE_COMPILER_FLAGS} -fprofile-abs-path")
+    endif()
+    include(CheckCCompilerFlag)
+    check_c_compiler_flag(-fprofile-abs-path HAVE_c_fprofile_abs_path)
+    if(HAVE_c_fprofile_abs_path)
+        set(COVERAGE_C_COMPILER_FLAGS "${COVERAGE_COMPILER_FLAGS} -fprofile-abs-path")
+    endif()
+endif()
+
+set(CMAKE_Fortran_FLAGS_COVERAGE
+    ${COVERAGE_COMPILER_FLAGS}
+    CACHE STRING "Flags used by the Fortran compiler during coverage builds."
+    FORCE )
+set(CMAKE_CXX_FLAGS_COVERAGE
+    ${COVERAGE_COMPILER_FLAGS}
+    CACHE STRING "Flags used by the C++ compiler during coverage builds."
+    FORCE )
+set(CMAKE_C_FLAGS_COVERAGE
+    ${COVERAGE_COMPILER_FLAGS}
+    CACHE STRING "Flags used by the C compiler during coverage builds."
+    FORCE )
+set(CMAKE_EXE_LINKER_FLAGS_COVERAGE
+    ""
+    CACHE STRING "Flags used for linking binaries during coverage builds."
+    FORCE )
+set(CMAKE_SHARED_LINKER_FLAGS_COVERAGE
+    ""
+    CACHE STRING "Flags used by the shared libraries linker during coverage builds."
+    FORCE )
+mark_as_advanced(
+    CMAKE_Fortran_FLAGS_COVERAGE
+    CMAKE_CXX_FLAGS_COVERAGE
+    CMAKE_C_FLAGS_COVERAGE
+    CMAKE_EXE_LINKER_FLAGS_COVERAGE
+    CMAKE_SHARED_LINKER_FLAGS_COVERAGE )
+
+get_property(GENERATOR_IS_MULTI_CONFIG GLOBAL PROPERTY GENERATOR_IS_MULTI_CONFIG)
+if(NOT (CMAKE_BUILD_TYPE STREQUAL "Debug" OR GENERATOR_IS_MULTI_CONFIG))
+    message(WARNING "Code coverage results with an optimised (non-Debug) build may be misleading")
+endif() # NOT (CMAKE_BUILD_TYPE STREQUAL "Debug" OR GENERATOR_IS_MULTI_CONFIG)
+
+if(CMAKE_C_COMPILER_ID STREQUAL "GNU" OR CMAKE_Fortran_COMPILER_ID STREQUAL "GNU")
+    link_libraries(gcov)
+endif()
+
+# Defines a target for running and collection code coverage information
+# Builds dependencies, runs the given executable and outputs reports.
+# NOTE! The executable should always have a ZERO as exit code otherwise
+# the coverage generation will not complete.
+#
+# setup_target_for_coverage_gcovr(
+#     NAME ctest_coverage                    # New target name
+#     EXECUTABLE ctest -j ${PROCESSOR_COUNT} # Executable in PROJECT_BINARY_DIR
+#     DEPENDENCIES executable_target         # Dependencies to build first
+#     BASE_DIRECTORY "../"                   # Base directory for report
+#                                            #  (defaults to PROJECT_SOURCE_DIR)
+#     FORMAT "cobertura"                     # Output format, one of:
+#                                            #  xml cobertura sonarqube json-summary
+#                                            #  json-details coveralls csv txt
+#                                            #  html-single html-nested html-details
+#                                            #  (xml is an alias to cobertura;
+#                                            #  if no format is set, defaults to xml)
+#     EXCLUDE "src/dir1/*" "src/dir2/*"      # Patterns to exclude (can be relative
+#                                            #  to BASE_DIRECTORY, with CMake 3.4+)
+# )
+# The user can set the variable GCOVR_ADDITIONAL_ARGS to supply additional flags to the
+# GCVOR command.
+function(setup_target_for_coverage_gcovr)
+    set(options NONE)
+    set(oneValueArgs BASE_DIRECTORY NAME FORMAT)
+    set(multiValueArgs EXCLUDE EXECUTABLE EXECUTABLE_ARGS DEPENDENCIES)
+    cmake_parse_arguments(Coverage "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
+
+    if(NOT GCOV_TOOL)
+        message(FATAL_ERROR "Could not find gcov or llvm-cov tool! Aborting...")
+    endif()
+
+    if(NOT GCOVR_PATH)
+        message(FATAL_ERROR "Could not find gcovr tool! Aborting...")
+    endif()
+
+    # Set base directory (as absolute path), or default to PROJECT_SOURCE_DIR
+    if(DEFINED Coverage_BASE_DIRECTORY)
+        get_filename_component(BASEDIR ${Coverage_BASE_DIRECTORY} ABSOLUTE)
+    else()
+        set(BASEDIR ${PROJECT_SOURCE_DIR})
+    endif()
+
+    if(NOT DEFINED Coverage_FORMAT)
+        set(Coverage_FORMAT xml)
+    endif()
+
+    if("--output" IN_LIST GCOVR_ADDITIONAL_ARGS)
+        message(FATAL_ERROR "Unsupported --output option detected in GCOVR_ADDITIONAL_ARGS! Aborting...")
+    else()
+        if((Coverage_FORMAT STREQUAL "html-details")
+            OR (Coverage_FORMAT STREQUAL "html-nested"))
+            set(GCOVR_OUTPUT_FILE ${PROJECT_BINARY_DIR}/${Coverage_NAME}/index.html)
+            set(GCOVR_CREATE_FOLDER ${PROJECT_BINARY_DIR}/${Coverage_NAME})
+        elseif(Coverage_FORMAT STREQUAL "html-single")
+            set(GCOVR_OUTPUT_FILE ${Coverage_NAME}.html)
+        elseif((Coverage_FORMAT STREQUAL "json-summary")
+            OR (Coverage_FORMAT STREQUAL "json-details")
+            OR (Coverage_FORMAT STREQUAL "coveralls"))
+            set(GCOVR_OUTPUT_FILE ${Coverage_NAME}.json)
+        elseif(Coverage_FORMAT STREQUAL "txt")
+            set(GCOVR_OUTPUT_FILE ${Coverage_NAME}.txt)
+        elseif(Coverage_FORMAT STREQUAL "csv")
+            set(GCOVR_OUTPUT_FILE ${Coverage_NAME}.csv)
+        else()
+            set(GCOVR_OUTPUT_FILE ${Coverage_NAME}.xml)
+        endif()
+    endif()
+
+    if ((Coverage_FORMAT STREQUAL "cobertura")
+        OR (Coverage_FORMAT STREQUAL "xml"))
+        list(APPEND GCOVR_ADDITIONAL_ARGS --cobertura "${GCOVR_OUTPUT_FILE}" )
+        list(APPEND GCOVR_ADDITIONAL_ARGS --cobertura-pretty )
+        set(Coverage_FORMAT cobertura) # overwrite xml
+    elseif(Coverage_FORMAT STREQUAL "sonarqube")
+        list(APPEND GCOVR_ADDITIONAL_ARGS --sonarqube "${GCOVR_OUTPUT_FILE}" )
+    elseif(Coverage_FORMAT STREQUAL "json-summary")
+        list(APPEND GCOVR_ADDITIONAL_ARGS --json-summary "${GCOVR_OUTPUT_FILE}" )
+        list(APPEND GCOVR_ADDITIONAL_ARGS --json-summary-pretty)
+    elseif(Coverage_FORMAT STREQUAL "json-details")
+        list(APPEND GCOVR_ADDITIONAL_ARGS --json "${GCOVR_OUTPUT_FILE}" )
+        list(APPEND GCOVR_ADDITIONAL_ARGS --json-pretty)
+    elseif(Coverage_FORMAT STREQUAL "coveralls")
+        list(APPEND GCOVR_ADDITIONAL_ARGS --coveralls "${GCOVR_OUTPUT_FILE}" )
+        list(APPEND GCOVR_ADDITIONAL_ARGS --coveralls-pretty)
+    elseif(Coverage_FORMAT STREQUAL "csv")
+        list(APPEND GCOVR_ADDITIONAL_ARGS --csv "${GCOVR_OUTPUT_FILE}" )
+    elseif(Coverage_FORMAT STREQUAL "txt")
+        list(APPEND GCOVR_ADDITIONAL_ARGS --txt "${GCOVR_OUTPUT_FILE}" )
+    elseif(Coverage_FORMAT STREQUAL "html-single")
+        list(APPEND GCOVR_ADDITIONAL_ARGS --html "${GCOVR_OUTPUT_FILE}" )
+        list(APPEND GCOVR_ADDITIONAL_ARGS --html-self-contained)
+    elseif(Coverage_FORMAT STREQUAL "html-nested")
+        list(APPEND GCOVR_ADDITIONAL_ARGS --html-nested "${GCOVR_OUTPUT_FILE}" )
+    elseif(Coverage_FORMAT STREQUAL "html-details")
+        list(APPEND GCOVR_ADDITIONAL_ARGS --html-details "${GCOVR_OUTPUT_FILE}" )
+    else()
+        message(FATAL_ERROR "Unsupported output style ${Coverage_FORMAT}! Aborting...")
+    endif()
+
+    # Collect excludes (CMake 3.4+: Also compute absolute paths)
+    set(GCOVR_EXCLUDES "")
+    foreach(EXCLUDE ${Coverage_EXCLUDE} ${COVERAGE_EXCLUDES} ${COVERAGE_GCOVR_EXCLUDES})
+        if(CMAKE_VERSION VERSION_GREATER 3.4)
+            get_filename_component(EXCLUDE ${EXCLUDE} ABSOLUTE BASE_DIR ${BASEDIR})
+        endif()
+        list(APPEND GCOVR_EXCLUDES "${EXCLUDE}")
+    endforeach()
+    list(REMOVE_DUPLICATES GCOVR_EXCLUDES)
+
+    # Combine excludes to several -e arguments
+    set(GCOVR_EXCLUDE_ARGS "")
+    foreach(EXCLUDE ${GCOVR_EXCLUDES})
+        list(APPEND GCOVR_EXCLUDE_ARGS "-e")
+        list(APPEND GCOVR_EXCLUDE_ARGS "${EXCLUDE}")
+    endforeach()
+
+    # Set up commands which will be run to generate coverage data
+    # Run tests
+    set(GCOVR_EXEC_TESTS_CMD
+        ${Coverage_EXECUTABLE} ${Coverage_EXECUTABLE_ARGS}
+    )
+
+    # Create folder
+    if(DEFINED GCOVR_CREATE_FOLDER)
+        set(GCOVR_FOLDER_CMD
+            ${CMAKE_COMMAND} -E make_directory ${GCOVR_CREATE_FOLDER})
+    else()
+        set(GCOVR_FOLDER_CMD echo) # dummy
+    endif()
+
+    # Running gcovr
+    set(GCOVR_CMD
+        ${GCOVR_PATH}
+        --gcov-executable ${GCOV_TOOL}
+        --gcov-ignore-parse-errors=negative_hits.warn_once_per_file
+        -r ${BASEDIR}
+        ${GCOVR_ADDITIONAL_ARGS}
+        ${GCOVR_EXCLUDE_ARGS}
+        --object-directory=${PROJECT_BINARY_DIR}
+    )
+
+    if(CODE_COVERAGE_VERBOSE)
+        message(STATUS "Executed command report")
+
+        message(STATUS "Command to run tests: ")
+        string(REPLACE ";" " " GCOVR_EXEC_TESTS_CMD_SPACED "${GCOVR_EXEC_TESTS_CMD}")
+        message(STATUS "${GCOVR_EXEC_TESTS_CMD_SPACED}")
+
+        if(NOT GCOVR_FOLDER_CMD STREQUAL "echo")
+            message(STATUS "Command to create a folder: ")
+            string(REPLACE ";" " " GCOVR_FOLDER_CMD_SPACED "${GCOVR_FOLDER_CMD}")
+            message(STATUS "${GCOVR_FOLDER_CMD_SPACED}")
+        endif()
+
+        message(STATUS "Command to generate gcovr coverage data: ")
+        string(REPLACE ";" " " GCOVR_CMD_SPACED "${GCOVR_CMD}")
+        message(STATUS "${GCOVR_CMD_SPACED}")
+    endif()
+
+    add_custom_target(${Coverage_NAME}
+        COMMAND ${GCOVR_EXEC_TESTS_CMD}
+        COMMAND ${GCOVR_FOLDER_CMD}
+        COMMAND ${GCOVR_CMD}
+
+        BYPRODUCTS ${GCOVR_OUTPUT_FILE}
+        WORKING_DIRECTORY ${PROJECT_BINARY_DIR}
+        DEPENDS ${Coverage_DEPENDENCIES}
+        VERBATIM # Protect arguments to commands
+        COMMENT "Running gcovr to produce code coverage report."
+    )
+
+    # Show info where to find the report
+    add_custom_command(TARGET ${Coverage_NAME} POST_BUILD
+        COMMAND ;
+        COMMENT "Code coverage report saved in ${GCOVR_OUTPUT_FILE} formatted as ${Coverage_FORMAT}"
+    )
+endfunction() # setup_target_for_coverage_gcovr
+
+function(append_coverage_compiler_flags)
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${COVERAGE_COMPILER_FLAGS}" PARENT_SCOPE)
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${COVERAGE_COMPILER_FLAGS}" PARENT_SCOPE)
+    set(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS} ${COVERAGE_COMPILER_FLAGS}" PARENT_SCOPE)
+    message(STATUS "Appending code coverage compiler flags: ${COVERAGE_COMPILER_FLAGS}")
+endfunction() # append_coverage_compiler_flags
+
+# Setup coverage for specific library
+function(append_coverage_compiler_flags_to_target name)
+    separate_arguments(_flag_list NATIVE_COMMAND "${COVERAGE_COMPILER_FLAGS}")
+    target_compile_options(${name} PRIVATE ${_flag_list})
+    if(CMAKE_C_COMPILER_ID STREQUAL "GNU" OR CMAKE_Fortran_COMPILER_ID STREQUAL "GNU")
+        target_link_libraries(${name} PRIVATE gcov)
+    endif()
+endfunction()

CMake/Docs.cmake

@@ -0,0 +1,11 @@
+find_package (Doxygen REQUIRED)
+
+set (DOXYGEN_IN ${CMAKE_CURRENT_SOURCE_DIR}/Doxyfile)
+set (DOXYGEN_OUT ${CMAKE_CURRENT_BINARY_DIR}/Doxyfile)
+
+configure_file (${DOXYGEN_IN} ${DOXYGEN_OUT} @ONLY)
+add_custom_target (docs
+    COMMAND ${DOXYGEN_EXECUTABLE} ${DOXYGEN_OUT}
+    WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
+    COMMENT "Generating API documentation with Doxygen"
+    VERBATIM)

CMake/Settings.cmake

@@ -0,0 +1,53 @@
+set(COMPILER_FLAGS
+  -Wall
+  -Wcast-align
+  -Wdouble-promotion
+  -Wextra
+  -Werror
+  -Wformat=2
+  -Wimplicit-fallthrough
+  -Wmisleading-indentation
+  -Wno-narrowing
+  -Wno-deprecated-declarations
+  -Wno-dangling-else
+  -Wno-unused-but-set-variable
+  -Wnon-virtual-dtor
+  -Wnull-dereference
+  -Wold-style-cast
+  -pedantic
+  -Wpedantic
+  -Wunused
+   # FIXME: The following bunch are needed for gcc12 atm.
+   -Wno-missing-requires
+   -Wno-restrict
+   -Wno-null-dereference
+   -Wno-maybe-uninitialized
+   -Wno-unknown-warning-option # and this to work with clang
+   # TODO: Address these and others in https://github.com/XRPLF/clio/issues/1273
+)
+
+#TODO: reenable when we change CI #884
+# if (is_gcc AND NOT lint)
+#   list(APPEND COMPILER_FLAGS
+#     -Wduplicated-branches
+#     -Wduplicated-cond
+#     -Wlogical-op
+#     -Wuseless-cast
+#   )
+# endif ()
+
+if (is_clang)
+  list(APPEND COMPILER_FLAGS
+    -Wshadow # gcc is to aggressive with shadowing https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78147
+  )
+endif ()
+
+if (is_appleclang)
+  list(APPEND COMPILER_FLAGS
+    -Wreorder-init-list
+  )
+endif ()
+
+# See https://github.com/cpp-best-practices/cppbestpractices/blob/master/02-Use_the_Tools_Available.md#gcc--clang for the flags description
+
+target_compile_options (clio PUBLIC ${COMPILER_FLAGS})

CMake/SourceLocation.cmake

@@ -0,0 +1,11 @@
+include (CheckIncludeFileCXX)
+
+check_include_file_cxx ("source_location" SOURCE_LOCATION_AVAILABLE)
+if (SOURCE_LOCATION_AVAILABLE) 
+    target_compile_definitions (clio PUBLIC "HAS_SOURCE_LOCATION")
+endif ()
+
+check_include_file_cxx ("experimental/source_location" EXPERIMENTAL_SOURCE_LOCATION_AVAILABLE)
+if (EXPERIMENTAL_SOURCE_LOCATION_AVAILABLE)     
+    target_compile_definitions (clio PUBLIC "HAS_EXPERIMENTAL_SOURCE_LOCATION")
+endif ()

CMake/coverage.cmake

@@ -1,126 +0,0 @@
-# call add_converage(module_name) to add coverage targets for the given module
-function(add_converage module)
-  if("${CMAKE_C_COMPILER_ID}" MATCHES "(Apple)?[Cc]lang"
-     OR "${CMAKE_CXX_COMPILER_ID}" MATCHES "(Apple)?[Cc]lang")
-    message("[Coverage] Building with llvm Code Coverage Tools")
-    # Using llvm gcov ; llvm install by xcode
-    set(LLVM_COV_PATH /Library/Developer/CommandLineTools/usr/bin)
-    if(NOT EXISTS ${LLVM_COV_PATH}/llvm-cov)
-      message(FATAL_ERROR "llvm-cov not found! Aborting.")
-    endif()
-
-    # set Flags
-    target_compile_options(${module} PRIVATE -fprofile-instr-generate
-                                             -fcoverage-mapping)
-    target_link_options(${module} PUBLIC -fprofile-instr-generate
-                        -fcoverage-mapping)
-
-    target_compile_options(clio PRIVATE -fprofile-instr-generate
-                                        -fcoverage-mapping)
-    target_link_options(clio PUBLIC -fprofile-instr-generate
-                        -fcoverage-mapping)
-
-    # llvm-cov
-    add_custom_target(
-      ${module}-ccov-preprocessing
-      COMMAND LLVM_PROFILE_FILE=${module}.profraw $<TARGET_FILE:${module}>
-      COMMAND ${LLVM_COV_PATH}/llvm-profdata merge -sparse ${module}.profraw -o
-              ${module}.profdata
-      DEPENDS ${module})
-
-    add_custom_target(
-      ${module}-ccov-show
-      COMMAND ${LLVM_COV_PATH}/llvm-cov show $<TARGET_FILE:${module}>
-              -instr-profile=${module}.profdata -show-line-counts-or-regions
-      DEPENDS ${module}-ccov-preprocessing)
-
-    # add summary for CI parse
-    add_custom_target(
-      ${module}-ccov-report
-      COMMAND
-        ${LLVM_COV_PATH}/llvm-cov report $<TARGET_FILE:${module}>
-        -instr-profile=${module}.profdata
-        -ignore-filename-regex=".*_makefiles|.*unittests|.*_deps"
-        -show-region-summary=false
-      DEPENDS ${module}-ccov-preprocessing)
-
-    # exclude libs and unittests self
-    add_custom_target(
-      ${module}-ccov
-      COMMAND
-        ${LLVM_COV_PATH}/llvm-cov show $<TARGET_FILE:${module}>
-        -instr-profile=${module}.profdata -show-line-counts-or-regions
-        -output-dir=${module}-llvm-cov -format="html"
-        -ignore-filename-regex=".*_makefiles|.*unittests|.*_deps" > /dev/null 2>&1
-      DEPENDS ${module}-ccov-preprocessing)
-
-    add_custom_command(
-      TARGET ${module}-ccov
-      POST_BUILD
-      COMMENT
-        "Open ${module}-llvm-cov/index.html in your browser to view the coverage report."
-    )
-  elseif("${CMAKE_C_COMPILER_ID}" MATCHES "GNU" OR "${CMAKE_CXX_COMPILER_ID}"
-                                                   MATCHES "GNU")
-    message("[Coverage] Building with Gcc Code Coverage Tools")
-
-    find_program(GCOV_PATH gcov)
-    if(NOT GCOV_PATH)
-      message(FATAL_ERROR "gcov not found! Aborting...")
-    endif() # NOT GCOV_PATH
-    find_program(GCOVR_PATH gcovr)
-    if(NOT GCOVR_PATH)
-      message(FATAL_ERROR "gcovr not found! Aborting...")
-    endif() # NOT GCOVR_PATH
-
-    set(COV_OUTPUT_PATH ${module}-gcc-cov)
-    target_compile_options(${module} PRIVATE -fprofile-arcs -ftest-coverage
-                                             -fPIC)
-    target_link_libraries(${module} PRIVATE gcov)
-
-    target_compile_options(clio PRIVATE -fprofile-arcs -ftest-coverage
-                                             -fPIC)
-    target_link_libraries(clio PRIVATE gcov)
-    # this target is used for CI as well generate the summary out.xml will send
-    # to github action to generate markdown, we can paste it to comments or
-    # readme
-    add_custom_target(
-      ${module}-ccov
-      COMMAND ${module} ${TEST_PARAMETER}
-      COMMAND rm -rf ${COV_OUTPUT_PATH}
-      COMMAND mkdir ${COV_OUTPUT_PATH}
-      COMMAND
-        gcovr -r ${CMAKE_SOURCE_DIR} --object-directory=${PROJECT_BINARY_DIR} -x
-        ${COV_OUTPUT_PATH}/out.xml --exclude='${CMAKE_SOURCE_DIR}/unittests/'
-        --exclude='${PROJECT_BINARY_DIR}/'
-      COMMAND
-        gcovr -r ${CMAKE_SOURCE_DIR} --object-directory=${PROJECT_BINARY_DIR}
-        --html ${COV_OUTPUT_PATH}/report.html
-        --exclude='${CMAKE_SOURCE_DIR}/unittests/'
-        --exclude='${PROJECT_BINARY_DIR}/'
-      WORKING_DIRECTORY ${PROJECT_BINARY_DIR}
-      COMMENT "Running gcovr to produce Cobertura code coverage report.")
-
-    # generate the detail report
-    add_custom_target(
-      ${module}-ccov-report
-      COMMAND ${module} ${TEST_PARAMETER}
-      COMMAND rm -rf ${COV_OUTPUT_PATH}
-      COMMAND mkdir ${COV_OUTPUT_PATH}
-      COMMAND
-        gcovr -r ${CMAKE_SOURCE_DIR} --object-directory=${PROJECT_BINARY_DIR}
-        --html-details ${COV_OUTPUT_PATH}/index.html
-        --exclude='${CMAKE_SOURCE_DIR}/unittests/'
-        --exclude='${PROJECT_BINARY_DIR}/'
-      WORKING_DIRECTORY ${PROJECT_BINARY_DIR}
-      COMMENT "Running gcovr to produce Cobertura code coverage report.")
-    add_custom_command(
-      TARGET ${module}-ccov-report
-      POST_BUILD
-      COMMENT
-        "Open ${COV_OUTPUT_PATH}/index.html in your browser to view the coverage report."
-    )
-  else()
-    message(FATAL_ERROR "Complier not support yet")
-  endif()
-endfunction()

CMake/deps/Boost.cmake

@@ -1,6 +1,11 @@
-set(Boost_USE_STATIC_LIBS ON)
-set(Boost_USE_STATIC_RUNTIME ON)
+set (Boost_USE_STATIC_LIBS ON)
+set (Boost_USE_STATIC_RUNTIME ON)
 
-find_package(Boost 1.75 COMPONENTS filesystem log_setup log thread system REQUIRED)
-
-target_link_libraries(clio PUBLIC ${Boost_LIBRARIES})
+find_package (Boost 1.82 REQUIRED
+  COMPONENTS
+    program_options
+    coroutine
+    system
+    log
+    log_setup
+)

CMake/deps/OpenSSL.cmake

@@ -0,0 +1,5 @@
+find_package (OpenSSL 1.1.1 REQUIRED)
+
+set_target_properties (OpenSSL::SSL PROPERTIES
+  INTERFACE_COMPILE_DEFINITIONS OPENSSL_NO_SSL2
+)

CMake/deps/Remove-bitset-operator.patch

@@ -1,24 +0,0 @@
-From 5cd9d09d960fa489a0c4379880cd7615b1c16e55 Mon Sep 17 00:00:00 2001
-From: CJ Cobb <ccobb@ripple.com>
-Date: Wed, 10 Aug 2022 12:30:01 -0400
-Subject: [PATCH] Remove bitset operator !=
-
----
- src/ripple/protocol/Feature.h | 1 -
- 1 file changed, 1 deletion(-)
-
-diff --git a/src/ripple/protocol/Feature.h b/src/ripple/protocol/Feature.h
-index b3ecb099b..6424be411 100644
---- a/src/ripple/protocol/Feature.h
-+++ b/src/ripple/protocol/Feature.h
-@@ -126,7 +126,6 @@ class FeatureBitset : private std::bitset<detail::numFeatures>
- public:
-     using base::bitset;
-     using base::operator==;
--    using base::operator!=;
- 
-     using base::all;
-     using base::any;
--- 
-2.32.0
-

CMake/deps/SourceLocation.cmake

@@ -1,11 +0,0 @@
-include(CheckIncludeFileCXX)
-
-check_include_file_cxx("source_location" SOURCE_LOCATION_AVAILABLE)
-if(SOURCE_LOCATION_AVAILABLE) 
-    target_compile_definitions(clio PUBLIC "HAS_SOURCE_LOCATION")
-endif()
-
-check_include_file_cxx("experimental/source_location" EXPERIMENTAL_SOURCE_LOCATION_AVAILABLE)
-if(EXPERIMENTAL_SOURCE_LOCATION_AVAILABLE)     
-    target_compile_definitions(clio PUBLIC "HAS_EXPERIMENTAL_SOURCE_LOCATION")
-endif()

CMake/deps/Threads.cmake

@@ -0,0 +1,2 @@
+set (THREADS_PREFER_PTHREAD_FLAG ON)
+find_package (Threads)

CMake/deps/cassandra.cmake

@@ -1,153 +1 @@
-find_package(ZLIB REQUIRED)
-
-find_library(cassandra NAMES cassandra)
-if(NOT cassandra)
-    message("System installed Cassandra cpp driver not found. Will build")
-    find_library(zlib NAMES zlib1g-dev zlib-devel zlib z)
-    if(NOT zlib)
-        message("zlib not found. will build")
-        add_library(zlib STATIC IMPORTED GLOBAL)
-        ExternalProject_Add(zlib_src
-            PREFIX ${nih_cache_path}
-            GIT_REPOSITORY https://github.com/madler/zlib.git
-            GIT_TAG v1.2.12
-            INSTALL_COMMAND ""
-            BUILD_BYPRODUCTS <BINARY_DIR>/${CMAKE_STATIC_LIBRARY_PREFIX}z.a
-            )
-        ExternalProject_Get_Property (zlib_src SOURCE_DIR)
-        ExternalProject_Get_Property (zlib_src BINARY_DIR)
-        set (zlib_src_SOURCE_DIR "${SOURCE_DIR}")
-        file (MAKE_DIRECTORY ${zlib_src_SOURCE_DIR}/include)
-        set_target_properties (zlib PROPERTIES
-            IMPORTED_LOCATION
-            ${BINARY_DIR}/${CMAKE_STATIC_LIBRARY_PREFIX}z.a
-            INTERFACE_INCLUDE_DIRECTORIES
-            ${SOURCE_DIR}/include)
-        add_dependencies(zlib zlib_src)
-        file(TO_CMAKE_PATH "${zlib_src_SOURCE_DIR}" zlib_src_SOURCE_DIR)
-    endif()
-    find_library(krb5 NAMES krb5-dev libkrb5-dev)
-    if(NOT krb5)
-        message("krb5 not found. will build")
-        add_library(krb5 STATIC IMPORTED GLOBAL)
-        ExternalProject_Add(krb5_src
-            PREFIX ${nih_cache_path}
-            GIT_REPOSITORY https://github.com/krb5/krb5.git
-            GIT_TAG krb5-1.20
-            UPDATE_COMMAND ""
-            CONFIGURE_COMMAND autoreconf src && CFLAGS=-fcommon ./src/configure --enable-static --disable-shared
-            BUILD_IN_SOURCE 1
-            BUILD_COMMAND make
-            INSTALL_COMMAND ""
-            BUILD_BYPRODUCTS <SOURCE_DIR>/lib/${CMAKE_STATIC_LIBRARY_PREFIX}krb5.a
-            )
-        message(${ep_lib_prefix}/krb5.a)
-        message(${CMAKE_STATIC_LIBRARY_PREFIX}krb5.a)
-        ExternalProject_Get_Property (krb5_src SOURCE_DIR)
-        ExternalProject_Get_Property (krb5_src BINARY_DIR)
-        set (krb5_src_SOURCE_DIR "${SOURCE_DIR}")
-        file (MAKE_DIRECTORY ${krb5_src_SOURCE_DIR}/include)
-        set_target_properties (krb5 PROPERTIES
-            IMPORTED_LOCATION
-	    ${SOURCE_DIR}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}krb5.a
-            INTERFACE_INCLUDE_DIRECTORIES
-            ${SOURCE_DIR}/include)
-        add_dependencies(krb5 krb5_src)
-        file(TO_CMAKE_PATH "${krb5_src_SOURCE_DIR}" krb5_src_SOURCE_DIR)
-    endif()
-
-
-    find_library(libuv1 NAMES uv1 libuv1 liubuv1-dev libuv1:amd64)
-
-
-    if(NOT libuv1)
-        message("libuv1 not found, will build")
-        add_library(libuv1 STATIC IMPORTED GLOBAL)
-        ExternalProject_Add(libuv_src
-            PREFIX ${nih_cache_path}
-            GIT_REPOSITORY https://github.com/libuv/libuv.git
-            GIT_TAG v1.44.1
-            INSTALL_COMMAND ""
-            BUILD_BYPRODUCTS <BINARY_DIR>/${CMAKE_STATIC_LIBRARY_PREFIX}uv_a.a
-            )
-
-        ExternalProject_Get_Property (libuv_src SOURCE_DIR)
-        ExternalProject_Get_Property (libuv_src BINARY_DIR)
-        set (libuv_src_SOURCE_DIR "${SOURCE_DIR}")
-        file (MAKE_DIRECTORY ${libuv_src_SOURCE_DIR}/include)
-
-        set_target_properties (libuv1 PROPERTIES
-            IMPORTED_LOCATION
-            ${BINARY_DIR}/${CMAKE_STATIC_LIBRARY_PREFIX}uv_a.a
-            INTERFACE_INCLUDE_DIRECTORIES
-            ${SOURCE_DIR}/include)
-        add_dependencies(libuv1 libuv_src)
-
-        file(TO_CMAKE_PATH "${libuv_src_SOURCE_DIR}" libuv_src_SOURCE_DIR)
-    endif()
-    add_library (cassandra STATIC IMPORTED GLOBAL)
-    ExternalProject_Add(cassandra_src
-        PREFIX ${nih_cache_path}
-        GIT_REPOSITORY https://github.com/datastax/cpp-driver.git
-        GIT_TAG 2.16.2
-        CMAKE_ARGS
-        -DLIBUV_ROOT_DIR=${BINARY_DIR}
-        -DLIBUV_INCLUDE_DIR=${SOURCE_DIR}/include
-        -DCASS_BUILD_STATIC=ON
-        -DCASS_BUILD_SHARED=OFF
-        INSTALL_COMMAND ""
-        BUILD_BYPRODUCTS <BINARY_DIR>/${CMAKE_STATIC_LIBRARY_PREFIX}cassandra_static.a
-        )
-
-    ExternalProject_Get_Property (cassandra_src SOURCE_DIR)
-    ExternalProject_Get_Property (cassandra_src BINARY_DIR)
-    set (cassandra_src_SOURCE_DIR "${SOURCE_DIR}")
-    file (MAKE_DIRECTORY ${cassandra_src_SOURCE_DIR}/include)
-
-    set_target_properties (cassandra PROPERTIES
-        IMPORTED_LOCATION
-        ${BINARY_DIR}/${CMAKE_STATIC_LIBRARY_PREFIX}cassandra_static.a
-        INTERFACE_INCLUDE_DIRECTORIES
-        ${SOURCE_DIR}/include)
-    message("cass dirs")
-    message(${BINARY_DIR})
-    message(${SOURCE_DIR})
-    message(${BINARY_DIR}/${CMAKE_STATIC_LIBRARY_PREFIX}cassandra_static.a)
-    add_dependencies(cassandra cassandra_src)
-
-    if(NOT libuv1)
-        ExternalProject_Add_StepDependencies(cassandra_src build libuv1)
-        target_link_libraries(cassandra INTERFACE libuv1)
-    else()
-        target_link_libraries(cassandra INTERFACE ${libuv1})
-    endif()
-    if(NOT krb5)
-
-        ExternalProject_Add_StepDependencies(cassandra_src build krb5)
-        target_link_libraries(cassandra INTERFACE krb5)
-    else()
-        target_link_libraries(cassandra INTERFACE ${krb5})
-    endif()
-
-    if(NOT zlib)
-        ExternalProject_Add_StepDependencies(cassandra_src build zlib)
-        target_link_libraries(cassandra INTERFACE zlib)
-    else()
-        target_link_libraries(cassandra INTERFACE ${zlib})
-    endif()
-	set(OPENSSL_USE_STATIC_LIBS TRUE)
-	find_package(OpenSSL REQUIRED)
-	target_link_libraries(cassandra INTERFACE OpenSSL::SSL)
-
-    file(TO_CMAKE_PATH "${cassandra_src_SOURCE_DIR}" cassandra_src_SOURCE_DIR)
-    target_link_libraries(clio PUBLIC cassandra)
-else()
-    message("Found system installed cassandra cpp driver")
-    message(${cassandra})
-    find_path(cassandra_includes NAMES cassandra.h REQUIRED)
-    message(${cassandra_includes})
-    get_filename_component(CASSANDRA_HEADER ${cassandra_includes}/cassandra.h REALPATH)
-    get_filename_component(CASSANDRA_HEADER_DIR ${CASSANDRA_HEADER} DIRECTORY)
-    target_link_libraries (clio PUBLIC ${cassandra})
-    target_include_directories(clio PUBLIC ${CASSANDRA_HEADER_DIR})
-endif()
+find_package (cassandra-cpp-driver REQUIRED)

CMake/deps/gtest.cmake

@@ -1,20 +1,4 @@
-FetchContent_Declare(
-  googletest
-  URL https://github.com/google/googletest/archive/609281088cfefc76f9d0ce82e1ff6c30cc3591e5.zip
-)
+find_package (GTest REQUIRED)
 
-FetchContent_GetProperties(googletest)
-
-if(NOT googletest_POPULATED)
-  FetchContent_Populate(googletest)
-  add_subdirectory(${googletest_SOURCE_DIR} ${googletest_BINARY_DIR} EXCLUDE_FROM_ALL)
-endif()
-
-target_link_libraries(clio_tests PUBLIC clio gmock_main)
-target_include_directories(clio_tests PRIVATE unittests)
-
-enable_testing()
-
-include(GoogleTest)
-
-gtest_discover_tests(clio_tests)
+enable_testing ()
+include (GoogleTest)

CMake/deps/libbacktrace.cmake

@@ -0,0 +1,3 @@
+target_compile_definitions(clio PUBLIC BOOST_STACKTRACE_LINK)
+target_compile_definitions(clio PUBLIC BOOST_STACKTRACE_USE_BACKTRACE)
+find_package(libbacktrace REQUIRED)

CMake/deps/libfmt.cmake

@@ -1,14 +1 @@
-FetchContent_Declare(
-  libfmt
-  URL https://github.com/fmtlib/fmt/releases/download/9.1.0/fmt-9.1.0.zip
-)
-
-FetchContent_GetProperties(libfmt)
-
-if(NOT libfmt_POPULATED)
-  FetchContent_Populate(libfmt)
-  add_subdirectory(${libfmt_SOURCE_DIR} ${libfmt_BINARY_DIR} EXCLUDE_FROM_ALL)
-endif()
-
-target_link_libraries(clio PUBLIC fmt)
-
+find_package (fmt REQUIRED)

CMake/deps/libxrpl.cmake

@@ -0,0 +1 @@
+find_package (xrpl REQUIRED)

CMake/deps/rippled.cmake

@@ -1,20 +0,0 @@
-set(RIPPLED_REPO "https://github.com/ripple/rippled.git")
-set(RIPPLED_BRANCH "1.9.2")
-set(NIH_CACHE_ROOT "${CMAKE_CURRENT_BINARY_DIR}" CACHE INTERNAL "")
-set(patch_command ! grep operator!= src/ripple/protocol/Feature.h || git apply < ${CMAKE_CURRENT_SOURCE_DIR}/CMake/deps/Remove-bitset-operator.patch)
-message(STATUS "Cloning ${RIPPLED_REPO} branch ${RIPPLED_BRANCH}")
-FetchContent_Declare(rippled
-  GIT_REPOSITORY "${RIPPLED_REPO}"
-  GIT_TAG "${RIPPLED_BRANCH}"
-  GIT_SHALLOW ON
-  PATCH_COMMAND "${patch_command}"
-)
-
-FetchContent_GetProperties(rippled)
-if(NOT rippled_POPULATED)
-  FetchContent_Populate(rippled)
-  add_subdirectory(${rippled_SOURCE_DIR} ${rippled_BINARY_DIR} EXCLUDE_FROM_ALL)
-endif()
-
-target_link_libraries(clio PUBLIC xrpl_core grpc_pbufs)
-target_include_directories(clio PUBLIC ${rippled_SOURCE_DIR}/src ) # TODO: Seems like this shouldn't be needed?

CMake/install/install.cmake

@@ -1,16 +1,14 @@
-set(CLIO_INSTALL_DIR "/opt/clio")
-set(CMAKE_INSTALL_PREFIX ${CLIO_INSTALL_DIR})
+set (CLIO_INSTALL_DIR "/opt/clio")
+set (CMAKE_INSTALL_PREFIX ${CLIO_INSTALL_DIR})
 
-install(TARGETS clio_server DESTINATION bin)
-# install(TARGETS clio_tests DESTINATION bin) # NOTE: Do we want to install the tests?
+install (TARGETS clio_server DESTINATION bin)
 
-#install(FILES example-config.json DESTINATION etc RENAME config.json)
-file(READ example-config.json config)
-string(REGEX REPLACE "./clio_log" "/var/log/clio/" config "${config}")
-file(WRITE ${CMAKE_BINARY_DIR}/install-config.json "${config}")
-install(FILES ${CMAKE_BINARY_DIR}/install-config.json DESTINATION etc RENAME config.json)
+file (READ example-config.json config)
+string (REGEX REPLACE "./clio_log" "/var/log/clio/" config "${config}")
+file (WRITE ${CMAKE_BINARY_DIR}/install-config.json "${config}")
+install (FILES ${CMAKE_BINARY_DIR}/install-config.json DESTINATION etc RENAME config.json)
 
-configure_file("${CMAKE_SOURCE_DIR}/CMake/install/clio.service.in" "${CMAKE_BINARY_DIR}/clio.service")
+configure_file ("${CMAKE_SOURCE_DIR}/CMake/install/clio.service.in" "${CMAKE_BINARY_DIR}/clio.service")
 
-install(FILES "${CMAKE_BINARY_DIR}/clio.service" DESTINATION /lib/systemd/system)
+install (FILES "${CMAKE_BINARY_DIR}/clio.service" DESTINATION /lib/systemd/system)
 

CMake/settings.cmake

@@ -1,6 +0,0 @@
-target_compile_options(clio  
-  PUBLIC -Wall
-         -Werror 
-         -Wno-narrowing
-         -Wno-deprecated-declarations 
-         -Wno-dangling-else)

CMakeLists.txt

@@ -1,75 +1,131 @@
 cmake_minimum_required(VERSION 3.16.3)
-
 project(clio)
 
-if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 11)
-  message(FATAL_ERROR "GCC 11+ required for building clio")
+# ========================================================================== #
+#                                   Options                                  #
+# ========================================================================== #
+option (verbose   "Verbose build"                                     FALSE)
+option (tests     "Build tests"                                       FALSE)
+option (docs      "Generate doxygen docs"                             FALSE)
+option (coverage  "Build test coverage report"                        FALSE)
+option (packaging "Create distribution packages"                      FALSE)
+option (lint      "Run clang-tidy checks during compilation"          FALSE)
+# ========================================================================== #
+set (san "" CACHE STRING "Add sanitizer instrumentation")
+set (CMAKE_EXPORT_COMPILE_COMMANDS TRUE)
+set_property (CACHE san PROPERTY STRINGS ";undefined;memory;address;thread")
+# ========================================================================== #
+
+# Include required modules
+include (CMake/Ccache.cmake)
+include (CheckCXXCompilerFlag)
+include (CMake/ClangTidy.cmake)
+
+# Set coverage build options
+if (tests AND coverage)
+  include (CMake/CodeCoverage.cmake)
+  append_coverage_compiler_flags()
 endif()
 
-option(BUILD_TESTS "Build tests" TRUE)
+if (verbose)
+  set (CMAKE_VERBOSE_MAKEFILE TRUE)
+endif ()
 
-option(VERBOSE "Verbose build" TRUE)
-if(VERBOSE)
-  set(CMAKE_VERBOSE_MAKEFILE TRUE)
-  set(FETCHCONTENT_QUIET FALSE CACHE STRING "Verbose FetchContent()")
-endif()
+if (packaging)
+  add_definitions (-DPKG=1)
+endif ()
 
+add_library (clio)
 
-if(PACKAGING)
-  add_definitions(-DPKG=1)
-endif()
+# Clio tweaks and checks
+include (CMake/CheckCompiler.cmake)
+include (CMake/Settings.cmake)
+include (CMake/ClioVersion.cmake)
+include (CMake/SourceLocation.cmake)
 
-#c++20 removed std::result_of but boost 1.75 is still using it.
-add_definitions(-DBOOST_ASIO_HAS_STD_INVOKE_RESULT=1)
+# Clio deps
+include (CMake/deps/libxrpl.cmake)
+include (CMake/deps/Boost.cmake)
+include (CMake/deps/OpenSSL.cmake)
+include (CMake/deps/Threads.cmake)
+include (CMake/deps/libfmt.cmake)
+include (CMake/deps/cassandra.cmake)
+include (CMake/deps/libbacktrace.cmake)
 
-add_library(clio)
-target_compile_features(clio PUBLIC cxx_std_20)
-target_include_directories(clio PUBLIC src)
+# TODO: Include directory will be wrong when installed.
+target_include_directories (clio PUBLIC src)
+target_compile_features (clio PUBLIC cxx_std_20)
 
-include(FetchContent)
-include(ExternalProject)
-include(CMake/settings.cmake)
-include(CMake/ClioVersion.cmake)
-include(CMake/deps/rippled.cmake)
-include(CMake/deps/libfmt.cmake)
-include(CMake/deps/Boost.cmake)
-include(CMake/deps/cassandra.cmake)
-include(CMake/deps/SourceLocation.cmake)
+target_link_libraries (clio
+  PUBLIC Boost::boost
+  PUBLIC Boost::coroutine
+  PUBLIC Boost::program_options
+  PUBLIC Boost::system
+  PUBLIC Boost::log
+  PUBLIC Boost::log_setup
+  PUBLIC Boost::stacktrace_backtrace
+  PUBLIC cassandra-cpp-driver::cassandra-cpp-driver
+  PUBLIC fmt::fmt
+  PUBLIC OpenSSL::Crypto
+  PUBLIC OpenSSL::SSL
+  PUBLIC xrpl::libxrpl
+  PUBLIC dl
+  PUBLIC libbacktrace::libbacktrace
 
-target_sources(clio PRIVATE
+  INTERFACE Threads::Threads
+)
+
+if (is_gcc)
+  # FIXME: needed on gcc for now
+  target_compile_definitions (clio PUBLIC BOOST_ASIO_DISABLE_CONCEPTS)
+endif ()
+
+target_sources (clio PRIVATE
   ## Main
   src/main/impl/Build.cpp
   ## Backend
-  src/backend/BackendInterface.cpp
-  src/backend/CassandraBackend.cpp
-  src/backend/SimpleCache.cpp
-  ## NextGen Backend
-  src/backend/cassandra/impl/Future.cpp
-  src/backend/cassandra/impl/Cluster.cpp
-  src/backend/cassandra/impl/Batch.cpp
-  src/backend/cassandra/impl/Result.cpp
-  src/backend/cassandra/impl/Tuple.cpp
-  src/backend/cassandra/impl/SslContext.cpp
-  src/backend/cassandra/Handle.cpp
-  src/backend/cassandra/SettingsProvider.cpp
+  src/data/BackendCounters.cpp
+  src/data/BackendInterface.cpp
+  src/data/LedgerCache.cpp
+  src/data/cassandra/impl/Future.cpp
+  src/data/cassandra/impl/Cluster.cpp
+  src/data/cassandra/impl/Batch.cpp
+  src/data/cassandra/impl/Result.cpp
+  src/data/cassandra/impl/Tuple.cpp
+  src/data/cassandra/impl/SslContext.cpp
+  src/data/cassandra/Handle.cpp
+  src/data/cassandra/SettingsProvider.cpp
   ## ETL
-  src/etl/ETLSource.cpp
-  src/etl/ProbingETLSource.cpp
+  src/etl/Source.cpp
+  src/etl/ProbingSource.cpp
   src/etl/NFTHelpers.cpp
-  src/etl/ReportingETL.cpp
-  ## Subscriptions
-  src/subscriptions/SubscriptionManager.cpp
+  src/etl/ETLService.cpp
+  src/etl/ETLState.cpp
+  src/etl/LoadBalancer.cpp
+  src/etl/impl/ForwardCache.cpp
+  ## Feed
+  src/feed/SubscriptionManager.cpp
+  src/feed/impl/TransactionFeed.cpp
+  src/feed/impl/LedgerFeed.cpp
+  src/feed/impl/ProposedTransactionFeed.cpp
+  src/feed/impl/SingleFeedBase.cpp
+  ## Web
+  src/web/impl/AdminVerificationStrategy.cpp
+  src/web/IntervalSweepHandler.cpp
+  src/web/Resolver.cpp
   ## RPC
   src/rpc/Errors.cpp
-  src/rpc/RPC.cpp
+  src/rpc/Factories.cpp
+  src/rpc/AMMHelpers.cpp
   src/rpc/RPCHelpers.cpp
   src/rpc/Counters.cpp
   src/rpc/WorkQueue.cpp
   src/rpc/common/Specs.cpp
   src/rpc/common/Validators.cpp
-  # RPC impl
+  src/rpc/common/MetaProcessors.cpp
+  src/rpc/common/impl/APIVersionParser.cpp
   src/rpc/common/impl/HandlerProvider.cpp
-  ## RPC handler
+  ## RPC handlers
   src/rpc/handlers/AccountChannels.cpp
   src/rpc/handlers/AccountCurrencies.cpp
   src/rpc/handlers/AccountInfo.cpp
@@ -78,13 +134,16 @@ target_sources(clio PRIVATE
   src/rpc/handlers/AccountObjects.cpp
   src/rpc/handlers/AccountOffers.cpp
   src/rpc/handlers/AccountTx.cpp
+  src/rpc/handlers/AMMInfo.cpp
   src/rpc/handlers/BookChanges.cpp
   src/rpc/handlers/BookOffers.cpp
+  src/rpc/handlers/DepositAuthorized.cpp
   src/rpc/handlers/GatewayBalances.cpp
   src/rpc/handlers/Ledger.cpp
   src/rpc/handlers/LedgerData.cpp
   src/rpc/handlers/LedgerEntry.cpp
   src/rpc/handlers/LedgerRange.cpp
+  src/rpc/handlers/NFTsByIssuer.cpp
   src/rpc/handlers/NFTBuyOffers.cpp
   src/rpc/handlers/NFTHistory.cpp
   src/rpc/handlers/NFTInfo.cpp
@@ -93,83 +152,209 @@ target_sources(clio PRIVATE
   src/rpc/handlers/NoRippleCheck.cpp
   src/rpc/handlers/Random.cpp
   src/rpc/handlers/TransactionEntry.cpp
-  src/rpc/handlers/Tx.cpp
   ## Util
-  src/config/Config.cpp
-  src/log/Logger.cpp
-  src/util/Taggable.cpp)
+  src/util/config/Config.cpp
+  src/util/log/Logger.cpp
+  src/util/prometheus/Http.cpp
+  src/util/prometheus/Label.cpp
+  src/util/prometheus/MetricBase.cpp
+  src/util/prometheus/MetricBuilder.cpp
+  src/util/prometheus/MetricsFamily.cpp
+  src/util/prometheus/OStream.cpp
+  src/util/prometheus/Prometheus.cpp
+  src/util/Random.cpp
+  src/util/requests/RequestBuilder.cpp
+  src/util/requests/Types.cpp
+  src/util/requests/WsConnection.cpp
+  src/util/requests/impl/SslContext.cpp
+  src/util/Taggable.cpp
+  src/util/TerminationHandler.cpp
+  src/util/TxUtils.cpp
+  src/util/LedgerUtils.cpp
+)
 
-add_executable(clio_server src/main/main.cpp)
-target_link_libraries(clio_server PUBLIC clio)
+# Clio server
+add_executable (clio_server src/main/Main.cpp)
+target_link_libraries (clio_server PRIVATE clio)
+target_link_options(clio_server
+  PRIVATE
+    $<$<AND:$<NOT:$<BOOL:${APPLE}>>,$<NOT:$<BOOL:${san}>>>:-static-libstdc++ -static-libgcc>
+)
 
-if(BUILD_TESTS)
-  set(TEST_TARGET clio_tests)
-  add_executable(${TEST_TARGET}
+# Unittesting
+if (tests)
+  set (TEST_TARGET clio_tests)
+  add_executable (${TEST_TARGET}
+    # Common
+    unittests/Main.cpp
     unittests/Playground.cpp
-    unittests/Backend.cpp
-    unittests/Logger.cpp
-    unittests/Config.cpp
-    unittests/ProfilerTest.cpp
-    unittests/DOSGuard.cpp
-    unittests/SubscriptionTest.cpp
-    unittests/SubscriptionManagerTest.cpp
+    unittests/LoggerTests.cpp
+    unittests/ConfigTests.cpp
+    unittests/ProfilerTests.cpp
+    unittests/JsonUtilTests.cpp
+    unittests/DOSGuardTests.cpp
+    unittests/util/TestGlobals.cpp
+    unittests/util/AssertTests.cpp
+    unittests/util/BatchingTests.cpp
+    unittests/util/TestHttpServer.cpp
     unittests/util/TestObject.cpp
+    unittests/util/TestWsServer.cpp
+    unittests/util/TxUtilTests.cpp
+    unittests/util/StringUtils.cpp
+    unittests/util/LedgerUtilsTests.cpp
+    unittests/util/prometheus/CounterTests.cpp
+    unittests/util/prometheus/GaugeTests.cpp
+    unittests/util/prometheus/HistogramTests.cpp
+    unittests/util/prometheus/HttpTests.cpp
+    unittests/util/prometheus/LabelTests.cpp
+    unittests/util/prometheus/MetricBuilderTests.cpp
+    unittests/util/prometheus/MetricsFamilyTests.cpp
+    unittests/util/prometheus/OStreamTests.cpp
+    unittests/util/requests/RequestBuilderTests.cpp
+    unittests/util/requests/SslContextTests.cpp
+    unittests/util/requests/WsConnectionTests.cpp
+    # ETL
+    unittests/etl/ExtractionDataPipeTests.cpp
+    unittests/etl/ExtractorTests.cpp
+    unittests/etl/TransformerTests.cpp
+    unittests/etl/CacheLoaderTests.cpp
+    unittests/etl/AmendmentBlockHandlerTests.cpp
+    unittests/etl/LedgerPublisherTests.cpp
+    unittests/etl/ETLStateTests.cpp
     # RPC
     unittests/rpc/ErrorTests.cpp
     unittests/rpc/BaseTests.cpp
-    unittests/rpc/RPCHelpersTest.cpp
-    unittests/rpc/CountersTest.cpp
-    unittests/rpc/AdminVerificationTest.cpp
+    unittests/rpc/RPCHelpersTests.cpp
+    unittests/rpc/CountersTests.cpp
+    unittests/rpc/APIVersionTests.cpp
+    unittests/rpc/ForwardingProxyTests.cpp
+    unittests/rpc/WorkQueueTests.cpp
+    unittests/rpc/AmendmentsTests.cpp
+    unittests/rpc/JsonBoolTests.cpp
     ## RPC handlers
     unittests/rpc/handlers/DefaultProcessorTests.cpp
     unittests/rpc/handlers/TestHandlerTests.cpp
-    unittests/rpc/handlers/AccountCurrenciesTest.cpp
-    unittests/rpc/handlers/AccountLinesTest.cpp
-    unittests/rpc/handlers/AccountTxTest.cpp
-    unittests/rpc/handlers/AccountOffersTest.cpp
-    unittests/rpc/handlers/AccountInfoTest.cpp
-    unittests/rpc/handlers/AccountChannelsTest.cpp
-    unittests/rpc/handlers/AccountNFTsTest.cpp
-    unittests/rpc/handlers/BookOffersTest.cpp
-    unittests/rpc/handlers/GatewayBalancesTest.cpp
-    unittests/rpc/handlers/TxTest.cpp
-    unittests/rpc/handlers/TransactionEntryTest.cpp
-    unittests/rpc/handlers/LedgerEntryTest.cpp
-    unittests/rpc/handlers/LedgerRangeTest.cpp
-    unittests/rpc/handlers/NoRippleCheckTest.cpp
-    unittests/rpc/handlers/ServerInfoTest.cpp
-    unittests/rpc/handlers/PingTest.cpp
-    unittests/rpc/handlers/RandomTest.cpp
-    unittests/rpc/handlers/NFTInfoTest.cpp
-    unittests/rpc/handlers/NFTBuyOffersTest.cpp
-    unittests/rpc/handlers/NFTSellOffersTest.cpp
-    unittests/rpc/handlers/NFTHistoryTest.cpp
-    unittests/rpc/handlers/SubscribeTest.cpp
-    unittests/rpc/handlers/UnsubscribeTest.cpp
-    unittests/rpc/handlers/LedgerDataTest.cpp
-    unittests/rpc/handlers/AccountObjectsTest.cpp
-    unittests/rpc/handlers/BookChangesTest.cpp
-    unittests/rpc/handlers/LedgerTest.cpp
+    unittests/rpc/handlers/AccountCurrenciesTests.cpp
+    unittests/rpc/handlers/AccountLinesTests.cpp
+    unittests/rpc/handlers/AccountTxTests.cpp
+    unittests/rpc/handlers/AccountOffersTests.cpp
+    unittests/rpc/handlers/AccountInfoTests.cpp
+    unittests/rpc/handlers/AccountChannelsTests.cpp
+    unittests/rpc/handlers/AccountNFTsTests.cpp
+    unittests/rpc/handlers/BookOffersTests.cpp
+    unittests/rpc/handlers/DepositAuthorizedTests.cpp
+    unittests/rpc/handlers/GatewayBalancesTests.cpp
+    unittests/rpc/handlers/TxTests.cpp
+    unittests/rpc/handlers/TransactionEntryTests.cpp
+    unittests/rpc/handlers/LedgerEntryTests.cpp
+    unittests/rpc/handlers/LedgerRangeTests.cpp
+    unittests/rpc/handlers/NoRippleCheckTests.cpp
+    unittests/rpc/handlers/ServerInfoTests.cpp
+    unittests/rpc/handlers/PingTests.cpp
+    unittests/rpc/handlers/RandomTests.cpp
+    unittests/rpc/handlers/NFTInfoTests.cpp
+    unittests/rpc/handlers/NFTBuyOffersTests.cpp
+    unittests/rpc/handlers/NFTsByIssuerTest.cpp
+    unittests/rpc/handlers/NFTSellOffersTests.cpp
+    unittests/rpc/handlers/NFTHistoryTests.cpp
+    unittests/rpc/handlers/SubscribeTests.cpp
+    unittests/rpc/handlers/UnsubscribeTests.cpp
+    unittests/rpc/handlers/LedgerDataTests.cpp
+    unittests/rpc/handlers/AccountObjectsTests.cpp
+    unittests/rpc/handlers/BookChangesTests.cpp
+    unittests/rpc/handlers/LedgerTests.cpp
+    unittests/rpc/handlers/VersionHandlerTests.cpp
+    unittests/rpc/handlers/AMMInfoTests.cpp
     # Backend
-    unittests/backend/cassandra/BaseTests.cpp
-    unittests/backend/cassandra/BackendTests.cpp
-    unittests/backend/cassandra/RetryPolicyTests.cpp
-    unittests/backend/cassandra/SettingsProviderTests.cpp
-    unittests/backend/cassandra/ExecutionStrategyTests.cpp
-    unittests/backend/cassandra/AsyncExecutorTests.cpp)
-  include(CMake/deps/gtest.cmake)
+    unittests/data/BackendFactoryTests.cpp
+    unittests/data/BackendInterfaceTests.cpp
+    unittests/data/BackendCountersTests.cpp
+    unittests/data/cassandra/BaseTests.cpp
+    unittests/data/cassandra/BackendTests.cpp
+    unittests/data/cassandra/RetryPolicyTests.cpp
+    unittests/data/cassandra/SettingsProviderTests.cpp
+    unittests/data/cassandra/ExecutionStrategyTests.cpp
+    unittests/data/cassandra/AsyncExecutorTests.cpp
+    # Webserver
+    unittests/web/AdminVerificationTests.cpp
+    unittests/web/ServerTests.cpp
+    unittests/web/RPCServerHandlerTests.cpp
+    unittests/web/WhitelistHandlerTests.cpp
+    unittests/web/SweepHandlerTests.cpp
+    # Feed
+    unittests/feed/SubscriptionManagerTests.cpp
+    unittests/feed/SingleFeedBaseTests.cpp
+    unittests/feed/ProposedTransactionFeedTests.cpp
+    unittests/feed/BookChangesFeedTests.cpp
+    unittests/feed/LedgerFeedTests.cpp
+    unittests/feed/TransactionFeedTests.cpp
+    unittests/feed/ForwardFeedTests.cpp
+    unittests/feed/TrackableSignalTests.cpp)
 
-  # test for dwarf5 bug on ci 
-  target_compile_options(clio PUBLIC -gdwarf-4)
+  include (CMake/deps/gtest.cmake)
 
-  # if CODE_COVERAGE enable, add clio_test-ccov
-  if(CODE_COVERAGE)
-    include(CMake/coverage.cmake)
-    add_converage(${TEST_TARGET})
-  endif()
-endif()
+  # See https://github.com/google/googletest/issues/3475
+  gtest_discover_tests (clio_tests DISCOVERY_TIMEOUT 10)
 
-include(CMake/install/install.cmake)
-if(PACKAGING)
-    include(CMake/packaging.cmake)
-endif()
+  # Fix for dwarf5 bug on ci
+  target_compile_options (clio PUBLIC -gdwarf-4)
+
+  target_compile_definitions (${TEST_TARGET} PUBLIC UNITTEST_BUILD)
+  target_include_directories (${TEST_TARGET} PRIVATE unittests)
+  target_link_libraries (${TEST_TARGET} PUBLIC clio gtest::gtest)
+
+  # Generate `coverage_report` target if coverage is enabled
+  if (coverage)
+    if (DEFINED CODE_COVERAGE_REPORT_FORMAT)
+      set(CODE_COVERAGE_FORMAT ${CODE_COVERAGE_REPORT_FORMAT})
+    else()
+      set(CODE_COVERAGE_FORMAT html-details)
+    endif()
+
+    if (DEFINED CODE_COVERAGE_TESTS_ARGS)
+      set(TESTS_ADDITIONAL_ARGS ${CODE_COVERAGE_TESTS_ARGS})
+      separate_arguments(TESTS_ADDITIONAL_ARGS)
+    else()
+      set(TESTS_ADDITIONAL_ARGS "")
+    endif()
+
+    set (GCOVR_ADDITIONAL_ARGS --exclude-throw-branches -s)
+
+    setup_target_for_coverage_gcovr(
+        NAME coverage_report
+        FORMAT ${CODE_COVERAGE_FORMAT}
+        EXECUTABLE clio_tests
+        EXECUTABLE_ARGS --gtest_brief=1 ${TESTS_ADDITIONAL_ARGS}
+        EXCLUDE "unittests"
+        DEPENDENCIES clio_tests
+    )
+  endif ()
+endif ()
+
+# Enable selected sanitizer if enabled via `san`
+if (san)
+  target_compile_options (clio
+    PUBLIC
+      # Sanitizers recommend minimum of -O1 for reasonable performance
+      $<$<CONFIG:Debug>:-O1>
+      ${SAN_FLAG}
+      -fno-omit-frame-pointer)
+  target_compile_definitions (clio
+    PUBLIC
+      $<$<STREQUAL:${san},address>:SANITIZER=ASAN>
+      $<$<STREQUAL:${san},thread>:SANITIZER=TSAN>
+      $<$<STREQUAL:${san},memory>:SANITIZER=MSAN>
+      $<$<STREQUAL:${san},undefined>:SANITIZER=UBSAN>)
+  target_link_libraries (clio INTERFACE ${SAN_FLAG} ${SAN_LIB})
+endif ()
+
+# Generate `docs` target for doxygen documentation if enabled
+# Note: use `make docs` to generate the documentation
+if (docs)
+  include (CMake/Docs.cmake)
+endif ()
+
+include (CMake/install/install.cmake)
+if (packaging)
+  include (CMake/packaging.cmake) # This file exists only in build runner
+endif ()

CONTRIBUTING.md

@@ -62,6 +62,11 @@ git commit --amend -S
 git push --force
 ```
 
+## Use ccache (optional)
+Clio uses ccache to speed up compilation. If you want to use it, please make sure it is installed on your machine.
+CMake will automatically detect it and use it if it's available.
+
+
 ## Fixing issues found during code review
 While your code is in review, it's possible that some changes will be requested by reviewer(s).
 This section describes the process of adding your fixes.
@@ -91,7 +96,7 @@ The button for that is near the bottom of the PR's page on GitHub.
 This is a non-exhaustive list of recommended style guidelines. These are not always strictly enforced and serve as a way to keep the codebase coherent.
 
 ## Formatting
-Code must conform to `clang-format` version 10, unless the result would be unreasonably difficult to read or maintain.
+Code must conform to `clang-format` version 17, unless the result would be unreasonably difficult to read or maintain.
 To change your code to conform use `clang-format -i <your changed files>`.
 
 ## Avoid
@@ -126,6 +131,7 @@ Existing maintainers can resign, or be subject to a vote for removal at the behe
 
 * [cindyyan317](https://github.com/cindyyan317) (Ripple)
 * [godexsoft](https://github.com/godexsoft) (Ripple)
+* [kuznetsss](https://github.com/kuznetsss) (Ripple)
 * [legleux](https://github.com/legleux) (Ripple)
 
 ## Honorable ex-Maintainers

Doxyfile

@@ -1,3 +1,16 @@
 PROJECT_NAME           = "Clio"
-INPUT                  = src
-RECURSIVE              = YES
+INPUT                  = ../src ../unittests
+EXCLUDE_PATTERNS       = *Test*.cpp *Test*.hpp
+RECURSIVE              = YES
+HAVE_DOT               = YES
+
+QUIET                  = YES
+WARNINGS               = NO
+WARN_NO_PARAMDOC       = NO
+WARN_IF_INCOMPLETE_DOC = NO
+WARN_IF_UNDOCUMENTED   = NO
+
+GENERATE_LATEX         = NO
+GENERATE_HTML          = YES
+
+SORT_MEMBERS_CTORS_1ST = YES

README.md

@@ -1,50 +1,123 @@
 # Clio
-Clio is an XRP Ledger API server. Clio is optimized for RPC calls, over WebSocket or JSON-RPC. Validated
-historical ledger and transaction data are stored in a more space-efficient format,
+[![Build status](https://github.com/XRPLF/clio/actions/workflows/build.yml/badge.svg?branch=develop)](https://github.com/XRPLF/clio/actions/workflows/build.yml?query=branch%3Adevelop)
+[![Nightly release status](https://github.com/XRPLF/clio/actions/workflows/nightly.yml/badge.svg?branch=develop)](https://github.com/XRPLF/clio/actions/workflows/nightly.yml?query=branch%3Adevelop)
+[![Clang-tidy checks status](https://github.com/XRPLF/clio/actions/workflows/clang-tidy.yml/badge.svg?branch=develop)](https://github.com/XRPLF/clio/actions/workflows/clang-tidy.yml?query=branch%3Adevelop)
+[![Code coverage develop branch](https://codecov.io/gh/XRPLF/clio/branch/develop/graph/badge.svg?)](https://app.codecov.io/gh/XRPLF/clio)
+
+Clio is an XRP Ledger API server. Clio is optimized for RPC calls, over WebSocket or JSON-RPC. 
+Validated historical ledger and transaction data are stored in a more space-efficient format,
 using up to 4 times less space than rippled. Clio can be configured to store data in Apache Cassandra or ScyllaDB,
-allowing for scalable read throughput. Multiple Clio nodes can share
-access to the same dataset, allowing for a highly available cluster of Clio nodes,
-without the need for redundant data storage or computation.
+allowing for scalable read throughput. Multiple Clio nodes can share access to the same dataset, 
+allowing for a highly available cluster of Clio nodes, without the need for redundant data storage or computation.
 
 Clio offers the full rippled API, with the caveat that Clio by default only returns validated data.
 This means that `ledger_index` defaults to `validated` instead of `current` for all requests.
 Other non-validated data is also not returned, such as information about queued transactions.
-For requests that require access to the p2p network, such as `fee` or `submit`, Clio automatically forwards the request to a rippled node and propagates the response back to the client. To access non-validated data for *any* request, simply add `ledger_index: "current"` to the request, and Clio will forward the request to rippled.
+For requests that require access to the p2p network, such as `fee` or `submit`, Clio automatically forwards the request to a rippled node and propagates the response back to the client. 
+To access non-validated data for *any* request, simply add `ledger_index: "current"` to the request, and Clio will forward the request to rippled.
 
 Clio does not connect to the peer-to-peer network. Instead, Clio extracts data from a group of specified rippled nodes. Running Clio requires access to at least one rippled node
 from which data can be extracted. The rippled node does not need to be running on the same machine as Clio.
 
+## Help
+Feel free to open an [issue](https://github.com/XRPLF/clio/issues) if you have a feature request or something doesn't work as expected.
+If you have any questions about building, running, contributing, using clio or any other, you could always start a new [discussion](https://github.com/XRPLF/clio/discussions).
 
 ## Requirements
 1. Access to a Cassandra cluster or ScyllaDB cluster. Can be local or remote.
-
 2. Access to one or more rippled nodes. Can be local or remote.
 
 ## Building
 
-Clio is built with CMake. Clio requires at least GCC-11/clang-14.0.0 (C++20), and Boost 1.75.0.
+Clio is built with CMake and uses Conan for managing dependencies. 
+It is written in C++20 and therefore requires a modern compiler.
 
-Use these instructions to build a Clio executable from the source. These instructions were tested on Ubuntu 20.04 LTS.
+## Prerequisites 
 
+### Minimum Requirements
+
+- [Python 3.7](https://www.python.org/downloads/)
+- [Conan 1.55](https://conan.io/downloads.html)
+- [CMake 3.16](https://cmake.org/download/)
+- [**Optional**] [GCovr](https://gcc.gnu.org/onlinedocs/gcc/Gcov.html) (needed for code coverage generation)
+- [**Optional**] [CCache](https://ccache.dev/) (speeds up compilation if you are going to compile Clio often)
+
+| Compiler    | Version |
+|-------------|---------|
+| GCC         | 11      |
+| Clang       | 14      |
+| Apple Clang | 14.0.3  |
+
+### Conan configuration
+
+Clio does not require anything but default settings in your (`~/.conan/profiles/default`) Conan profile. It's best to have no extra flags specified. 
+> Mac example:
+```
+[settings]
+os=Macos
+os_build=Macos
+arch=armv8
+arch_build=armv8
+compiler=apple-clang
+compiler.version=14
+compiler.libcxx=libc++
+build_type=Release
+compiler.cppstd=20
+```
+> Linux example:
+```
+[settings]
+os=Linux
+os_build=Linux
+arch=x86_64
+arch_build=x86_64
+compiler=gcc
+compiler.version=11
+compiler.libcxx=libstdc++11
+build_type=Release
+compiler.cppstd=20
+```
+
+### Artifactory
+
+1. Make sure artifactory is setup with Conan
 ```sh
-# Install dependencies
-  sudo apt-get -y install git pkg-config protobuf-compiler libprotobuf-dev libssl-dev wget build-essential bison flex autoconf cmake clang-format
-# Install gcovr to run code coverage
-  sudo apt-get -y install gcovr
+conan remote add --insert 0 conan-non-prod http://18.143.149.228:8081/artifactory/api/conan/conan-non-prod
+```
+Now you should be able to download prebuilt `xrpl` package on some platforms.
 
-# Compile Boost
-  wget -O $HOME/boost_1_75_0.tar.gz https://boostorg.jfrog.io/artifactory/main/release/1.75.0/source/boost_1_75_0.tar.gz
-  tar xvzf $HOME/boost_1_75_0.tar.gz
-  cd $HOME/boost_1_75_0
-  ./bootstrap.sh
-  ./b2 -j$(nproc)
-  echo "export BOOST_ROOT=$HOME/boost_1_75_0" >> $HOME/.profile && source $HOME/.profile
+You might need to edit the `~/.conan/remotes.json` file to ensure that this newly added artifactory is listed last. Otherwise you might see compilation errors when building the project with gcc version 13 (or newer).
 
-# Clone the Clio Git repository & build Clio
-  cd $HOME
-  git clone https://github.com/XRPLF/clio.git
-  cd $HOME/clio
-  cmake -B build && cmake --build build --parallel $(nproc)
+2. Remove old packages you may have cached: 
+```sh 
+conan remove -f xrpl
+```
+
+## Building Clio
+
+Navigate to Clio's root directory and perform
+```sh
+mkdir build && cd build
+conan install .. --output-folder . --build missing --settings build_type=Release -o tests=True -o lint=False
+cmake -DCMAKE_TOOLCHAIN_FILE:FILEPATH=build/generators/conan_toolchain.cmake -DCMAKE_BUILD_TYPE=Release ..
+cmake --build . --parallel 8 # or without the number if you feel extra adventurous
+```
+If all goes well, `conan install` will find required packages and `cmake` will do the rest. you should end up with `clio_server` and `clio_tests` in the `build` directory (the current directory).
+
+> **Tip:** You can omit the `-o tests=True` in `conan install` command above if you don't want to build `clio_tests`.
+
+> **Tip:** To generate a Code Coverage report, include `-o coverage=True` in the `conan install` command above, along with `-o tests=True` to enable tests. After running the `cmake` commands, execute `make clio_tests-ccov`. The coverage report will be found at `clio_tests-llvm-cov/index.html`.
+
+## Building Clio with Docker
+
+It is possible to build Clio using docker if you don't want to install all the dependencies on your machine.
+```sh
+docker run -it rippleci/clio_ci:latest
+git clone https://github.com/XRPLF/clio
+mkdir build && cd build
+conan install .. --output-folder . --build missing --settings build_type=Release -o tests=True -o lint=False
+cmake -DCMAKE_TOOLCHAIN_FILE:FILEPATH=build/generators/conan_toolchain.cmake -DCMAKE_BUILD_TYPE=Release ..
+cmake --build . --parallel 8 # or without the number if you feel extra adventurous
 ```
 
 ## Running
@@ -96,12 +169,12 @@ The parameters `ssl_cert_file` and `ssl_key_file` can also be added to the top l
 An example of how to specify `ssl_cert_file` and `ssl_key_file` in the config:
 
 ```json
-"server":{
+"server": {
     "ip": "0.0.0.0",
     "port": 51233
 },
-"ssl_cert_file" : "/full/path/to/cert.file",
-"ssl_key_file" : "/full/path/to/key.file"
+"ssl_cert_file": "/full/path/to/cert.file",
+"ssl_key_file": "/full/path/to/key.file"
 ```
 
 Once your config files are ready, start rippled and Clio. It doesn't matter which you
@@ -172,6 +245,105 @@ which can cause high latencies. A possible alternative to this is to just deploy
 a database in each region, and the Clio nodes in each region use their region's database.
 This is effectively two systems.
 
+Clio supports API versioning as [described here](https://xrpl.org/request-formatting.html#api-versioning).
+It's possible to configure `minimum`, `maximum` and `default` version like so:
+```json
+"api_version": {
+    "min": 1,
+    "max": 2,
+    "default": 1
+}
+```
+All of the above are optional.
+Clio will fallback to hardcoded defaults when not specified in the config file or configured values are outside
+of the minimum and maximum supported versions hardcoded in `src/rpc/common/APIVersion.h`.
+> **Note:** See `example-config.json` for more details. 
+
+## Admin rights for requests
+
+By default clio checks admin privileges by IP address from request (only `127.0.0.1` is considered to be an admin).
+It is not very secure because the IP could be spoofed.
+For a better security `admin_password` could be provided in the `server` section of clio's config:
+```json
+"server": {
+    "admin_password": "secret"
+}
+```
+If the password is presented in the config, clio will check the Authorization header (if any) in each request for the password.
+The Authorization header should contain type `Password` and the password from the config, e.g. `Password secret`.
+Exactly equal password gains admin rights for the request or a websocket connection.
+
+## Prometheus metrics collection
+
+Clio natively supports Prometheus metrics collection. It accepts Prometheus requests on the port configured in `server` section of config.
+Prometheus metrics are enabled by default. To disable it add `"prometheus": { "enabled": false }` to the config.
+It is important to know that clio responds to Prometheus request only if they are admin requests, so Prometheus should be configured to send admin password in header.
+There is an example of docker-compose file, Prometheus and Grafana configs in [examples/infrastructure](examples/infrastructure).
+
+## Using clang-tidy for static analysis
+
+Minimum clang-tidy version required is 17.0.
+Clang-tidy could be run by cmake during building the project.
+For that provide the option `-o lint=True` for `conan install` command:
+```sh
+conan install .. --output-folder . --build missing --settings build_type=Release -o tests=True -o lint=True
+```
+By default cmake will try to find clang-tidy automatically in your system.
+To force cmake use desired binary set `CLIO_CLANG_TIDY_BIN` environment variable as path to clang-tidy binary.
+E.g.:
+```sh
+export CLIO_CLANG_TIDY_BIN=/opt/homebrew/opt/llvm@17/bin/clang-tidy
+```
+
+## Coverage report
+
+Coverage report is intended for the developers using compilers GCC
+or Clang (including Apple Clang). It is generated by the build target `coverage_report`,
+which is only enabled when both `tests` and `coverage` options are set, e.g. with
+`-o coverage=True -o tests=True` in `conan`
+
+Prerequisites for the coverage report:
+
+- [gcovr tool](https://gcovr.com/en/stable/getting-started.html) (can be installed e.g. with `pip install gcovr`)
+- `gcov` for GCC (installed with the compiler by default) or
+- `llvm-cov` for Clang (installed with the compiler by default, also on Apple)
+- `Debug` build type
+
+Coverage report is created when the following steps are completed, in order:
+
+1. `clio_tests` binary built with the instrumentation data, enabled by the `coverage`
+   option mentioned above
+2. completed run of unit tests, which populates coverage capture data
+3. completed run of `gcovr` tool (which internally invokes either `gcov` or `llvm-cov`)
+   to assemble both instrumentation data and coverage capture data into a coverage report
+
+Above steps are automated into a single target `coverage_report`. The instrumented
+`clio_tests` binary can be also used for running regular unit tests. In case of a
+spurious failure of unit tests, it is possile to re-run `coverage_report` target without
+rebuilding the `clio_tests` binary (since it is simply a dependency of the coverage report target).
+
+The default coverage report format is `html-details`, but the developers
+can override it to any of the formats listed in `CMake/CodeCoverage.cmake`
+by setting `CODE_COVERAGE_REPORT_FORMAT` variable in `cmake`. For example, CI
+is setting this parameter to `xml` for the [codecov](codecov.io) integration.
+
+In case if some unit tests predictably fail e.g. due to absence of a Cassandra database, it is possible
+to set unit tests options in `CODE_COVERAGE_TESTS_ARGS` cmake variable, as demonstrated below:
+
+```
+cd .build
+conan install .. --output-folder . --build missing --settings build_type=Debug -o tests=True -o coverage=True
+cmake -DCODE_COVERAGE_REPORT_FORMAT=json-details -DCMAKE_BUILD_TYPE=Debug -DCODE_COVERAGE_TESTS_ARGS="--gtest_filter=-BackendCassandra*" -DCMAKE_TOOLCHAIN_FILE:FILEPATH=build/generators/conan_toolchain.cmake ..
+cmake --build . --target coverage_report
+```
+
+After `coverage_report` target is completed, the generated coverage report will be
+stored inside the build directory, as either of:
+
+- file named `coverage_report.*`, with a suitable extension for the report format, or
+- directory named `coverage_report`, with `index.html` and other files inside, for `html-details` or `html-nested` report formats.
+
+
 ## Developing against `rippled` in standalone mode
 
 If you wish you develop against a `rippled` instance running in standalone

cloud-example-config.json

@@ -1,38 +1,43 @@
+/*
+ * This is an example configuration file. Please do not use without modifying to suit your needs.
+ */
 {
-    "database":
-    {
-        "type":"cassandra",
-        "cassandra":
-        {
-            "secure_connect_bundle":"[path/to/zip. ignore if using contact_points]",
-            "contact_points":"[ip. ignore if using secure_connect_bundle]",
-            "port":"[port. ignore if using_secure_connect_bundle]",
-            "keyspace":"clio",
-            "username":"[username, if any]",
-            "password":"[password, if any]",
-            "max_requests_outstanding":25000,
-            "threads":8
+    "database": {
+        "type": "cassandra",
+        "cassandra": {
+            // This option can be used to setup a secure connect bundle connection
+            "secure_connect_bundle": "[path/to/zip. ignore if using contact_points]",
+            // The following options are used only if using contact_points
+            "contact_points": "[ip. ignore if using secure_connect_bundle]",
+            "port": "[port. ignore if using_secure_connect_bundle]",
+            // Authentication settings
+            "username": "[username, if any]",
+            "password": "[password, if any]",
+            // Other common settings
+            "keyspace": "clio",
+            "max_write_requests_outstanding": 25000,
+            "max_read_requests_outstanding": 30000,
+            "threads": 8
         }
     },
-    "etl_sources":
-    [
+    "etl_sources": [
         {
-            "ip":"[rippled ip]",
-            "ws_port":"6006",
-            "grpc_port":"50051"
+            "ip": "[rippled ip]",
+            "ws_port": "6006",
+            "grpc_port": "50051"
         }
     ],
-    "dos_guard":
-    {
-        "whitelist":["127.0.0.1"]
+    "dos_guard": {
+        "whitelist": [
+            "127.0.0.1"
+        ]
     },
-    "server":{
-        "ip":"0.0.0.0",
-        "port":8080
+    "server": {
+        "ip": "0.0.0.0",
+        "port": 8080
     },
-    "log_level":"debug",
-    "log_file":"./clio.log",
-    "online_delete":0,
-    "extractor_threads":8,
-    "read_only":false
+    "log_level": "debug",
+    "log_file": "./clio.log",
+    "extractor_threads": 8,
+    "read_only": false
 }

conanfile.py

@@ -0,0 +1,92 @@
+from conan import ConanFile
+from conan.tools.cmake import CMake, CMakeToolchain, cmake_layout
+
+
+class Clio(ConanFile):
+    name = 'clio'
+    license = 'ISC'
+    author = 'Alex Kremer <akremer@ripple.com>, John Freeman <jfreeman@ripple.com>'
+    url = 'https://github.com/xrplf/clio'
+    description = 'Clio RPC server'
+    settings = 'os', 'compiler', 'build_type', 'arch'
+    options = {
+        'fPIC': [True, False],
+        'verbose': [True, False],
+        'tests': [True, False],     # build unit tests; create `clio_tests` binary
+        'docs': [True, False],      # doxygen API docs; create custom target 'docs'
+        'packaging': [True, False], # create distribution packages
+        'coverage': [True, False],  # build for test coverage report; create custom target `clio_tests-ccov`
+        'lint': [True, False],      # run clang-tidy checks during compilation
+    }
+
+    requires = [
+        'boost/1.82.0',
+        'cassandra-cpp-driver/2.17.0',
+        'fmt/10.1.1',
+        'protobuf/3.21.9',
+        'grpc/1.50.1',
+        'openssl/1.1.1u',
+        'xrpl/2.2.0',
+        'libbacktrace/cci.20210118'
+    ]
+
+    default_options = {
+        'fPIC': True,
+        'verbose': False,
+        'tests': False,
+        'packaging': False,
+        'coverage': False,
+        'lint': False,
+        'docs': False,
+        
+        'xrpl/*:tests': False,
+        'cassandra-cpp-driver/*:shared': False,
+        'date/*:header_only': True,
+        'grpc/*:shared': False,
+        'grpc/*:secure': True,
+        'libpq/*:shared': False,
+        'lz4/*:shared': False,
+        'openssl/*:shared': False,
+        'protobuf/*:shared': False,
+        'protobuf/*:with_zlib': True,
+        'snappy/*:shared': False,
+        'gtest/*:no_main': True,
+    }
+
+    exports_sources = (
+        'CMakeLists.txt', 'CMake/*', 'src/*'
+    )
+
+    def requirements(self):
+        if self.options.tests:
+            self.requires('gtest/1.14.0')
+
+    def configure(self):
+        if self.settings.compiler == 'apple-clang':
+            self.options['boost'].visibility = 'global'
+
+    def layout(self):
+        cmake_layout(self)
+        # Fix this setting to follow the default introduced in Conan 1.48 
+        # to align with our build instructions.
+        self.folders.generators = 'build/generators'
+
+    generators = 'CMakeDeps'
+    def generate(self):
+        tc = CMakeToolchain(self)
+        tc.variables['verbose'] = self.options.verbose
+        tc.variables['tests'] = self.options.tests
+        tc.variables['coverage'] = self.options.coverage
+        tc.variables['lint'] = self.options.lint
+        tc.variables['docs'] = self.options.docs
+        tc.variables['packaging'] = self.options.packaging
+        tc.generate()
+
+    def build(self):
+        cmake = CMake(self)
+        cmake.configure()
+        cmake.build()
+
+    def package(self):
+        cmake = CMake(self)
+        cmake.install()

docker/ci/dockerfile

@@ -0,0 +1,67 @@
+FROM ubuntu:focal
+ARG DEBIAN_FRONTEND=noninteractive
+ARG TARGETARCH
+
+USER root
+WORKDIR /root/
+
+ENV GCC_VERSION=11 \
+    CCACHE_VERSION=4.8.3 \
+    LLVM_TOOLS_VERSION=17 \
+    GH_VERSION=2.40.0
+ 
+# Add repositories
+RUN apt-get -qq update \
+    && apt-get -qq install -y --no-install-recommends --no-install-suggests gnupg wget curl software-properties-common \
+    && add-apt-repository -y ppa:ubuntu-toolchain-r/test \
+    && wget -O - https://apt.kitware.com/keys/kitware-archive-latest.asc 2>/dev/null | apt-key add - \
+    && apt-add-repository 'deb https://apt.kitware.com/ubuntu/ focal main' \
+    && echo "deb http://apt.llvm.org/focal/ llvm-toolchain-focal-${LLVM_TOOLS_VERSION} main" >> /etc/apt/sources.list \
+    && wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | apt-key add -
+
+# Install packages
+RUN apt update -qq \
+    && apt install -y --no-install-recommends --no-install-suggests cmake python3 python3-pip sudo git \
+    ninja-build make pkg-config libzstd-dev libzstd1 g++-${GCC_VERSION} jq \
+    clang-format-${LLVM_TOOLS_VERSION} clang-tidy-${LLVM_TOOLS_VERSION} clang-tools-${LLVM_TOOLS_VERSION} \
+    && update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-${GCC_VERSION} 100 \
+    && update-alternatives --install /usr/bin/c++ c++ /usr/bin/g++-${GCC_VERSION} 100 \
+    && update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-${GCC_VERSION} 100 \
+    && update-alternatives --install /usr/bin/cc cc /usr/bin/gcc-${GCC_VERSION} 100 \
+    && update-alternatives --install /usr/bin/gcov gcov /usr/bin/gcov-${GCC_VERSION} 100 \
+    && update-alternatives --install /usr/bin/gcov-dump gcov-dump /usr/bin/gcov-dump-${GCC_VERSION} 100 \
+    && update-alternatives --install /usr/bin/gcov-tool gcov-tool /usr/bin/gcov-tool-${GCC_VERSION} 100 \
+    && apt-get clean && apt remove -y software-properties-common \
+    && pip3 install  -q --upgrade --no-cache-dir pip \
+    && pip3 install  -q --no-cache-dir conan==1.62 gcovr
+
+# Install ccache from source
+WORKDIR /tmp
+RUN wget "https://github.com/ccache/ccache/releases/download/v${CCACHE_VERSION}/ccache-${CCACHE_VERSION}.tar.gz" \
+    && tar xf "ccache-${CCACHE_VERSION}.tar.gz" \
+    && cd "ccache-${CCACHE_VERSION}" \
+    && mkdir build && cd build \
+    && cmake -GNinja -DCMAKE_BUILD_TYPE=Release .. \
+    && ninja && cp ./ccache /usr/bin/ccache
+
+# Install gh
+RUN wget https://github.com/cli/cli/releases/download/v${GH_VERSION}/gh_${GH_VERSION}_linux_${TARGETARCH}.tar.gz \
+    && tar xf gh_${GH_VERSION}_linux_${TARGETARCH}.tar.gz \
+    && mv gh_${GH_VERSION}_linux_${TARGETARCH}/bin/gh /usr/bin/gh
+
+# Clean up
+RUN rm -rf  /tmp/* /var/tmp/*
+
+WORKDIR /root/
+# Using root by default is not very secure but github checkout action doesn't work with any other user
+# https://github.com/actions/checkout/issues/956
+# And Github Actions doc recommends using root
+# https://docs.github.com/en/actions/creating-actions/dockerfile-support-for-github-actions#user
+
+# Setup conan
+RUN conan profile new default --detect \
+    && conan profile update settings.compiler.cppstd=20 default \
+    && conan profile update settings.compiler.libcxx=libstdc++11 default \
+    && conan remote add --insert 0 conan-non-prod http://18.143.149.228:8081/artifactory/api/conan/conan-non-prod
+
+

example-config.json

@@ -1,3 +1,6 @@
+/*
+ * This is an example configuration file. Please do not use without modifying to suit your needs.
+ */
 {
     "database": {
         "type": "cassandra",
@@ -9,9 +12,22 @@
             "table_prefix": "",
             "max_write_requests_outstanding": 25000,
             "max_read_requests_outstanding": 30000,
-            "threads": 8
+            "threads": 8,
+            //
+            // Advanced options. USE AT OWN RISK:
+            // ---
+            "core_connections_per_host": 1, // Defaults to 1
+            "write_batch_size": 20 // Defaults to 20
+            //
+            // Below options will use defaults from cassandra driver if left unspecified.
+            // See https://docs.datastax.com/en/developer/cpp-driver/2.17/api/struct.CassCluster/ for details.
+            // 
+            // "queue_size_io": 2
+            //
+            // ---
         }
     },
+    "allow_no_etl": false, // Allow Clio to run without valid ETL source, otherwise Clio will stop if ETL check fails
     "etl_sources": [
         {
             "ip": "127.0.0.1",
@@ -20,21 +36,24 @@
         }
     ],
     "dos_guard": {
+        // Comma-separated list of IPs to exclude from rate limiting
         "whitelist": [
             "127.0.0.1"
-        ], // comma-separated list of ips to exclude from rate limiting
-        /* The below values are the default values and are only specified here
-         * for documentation purposes. The rate limiter currently limits
-         * connections and bandwidth per ip. The rate limiter looks at the raw
-         * ip of a client connection, and so requests routed through a load
-         * balancer will all have the same ip and be treated as a single client
-         */
-        "max_fetches": 1000000, // max bytes per ip per sweep interval
-        "max_connections": 20, // max connections per ip
-        "max_requests": 20, // max connections per ip
-        "sweep_interval": 1 // time in seconds before resetting bytes per ip count
+        ],
+        //
+        // The below values are the default values and are only specified here
+        // for documentation purposes. The rate limiter currently limits
+        // connections and bandwidth per IP. The rate limiter looks at the raw
+        // IP of a client connection, and so requests routed through a load
+        // balancer will all have the same IP and be treated as a single client.
+        //
+        "max_fetches": 1000000, // Max bytes per IP per sweep interval
+        "max_connections": 20, // Max connections per IP
+        "max_requests": 20, // Max connections per IP per sweep interval
+        "sweep_interval": 1 // Time in seconds before resetting max_fetches and max_requests
     },
     "cache": {
+        // Comma-separated list of peer nodes that Clio can use to download cache from at startup
         "peers": [
             {
                 "ip": "127.0.0.1",
@@ -45,11 +64,18 @@
     "server": {
         "ip": "0.0.0.0",
         "port": 51233,
-        /* Max number of requests to queue up before rejecting further requests.
-        * Defaults to 0, which disables the limit
-        */
-        "max_queue_size": 500
+        // Max number of requests to queue up before rejecting further requests.
+        // Defaults to 0, which disables the limit.
+        "max_queue_size": 500,
+        // If request contains header with authorization, Clio will check if it matches the prefix 'Password ' + this value's sha256 hash
+        // If matches, the request will be considered as admin request
+        "admin_password": "xrp",
+        // If local_admin is true, Clio will consider requests come from 127.0.0.1 as admin requests
+        // It's true by default unless admin_password is set,'local_admin' : true and 'admin_password' can not be set at the same time
+        "local_amdin": false
     },
+    // Overrides log level on a per logging channel.
+    // Defaults to global "log_level" for each unspecified channel.
     "log_channels": [
         {
             "channel": "Backend",
@@ -76,18 +102,29 @@
             "log_level": "trace"
         }
     ],
+    "prometheus": {
+        "enabled": true,
+        "compress_reply": true
+    },
     "log_level": "info",
-    "log_format": "%TimeStamp% (%SourceLocation%) [%ThreadID%] %Channel%:%Severity% %Message%", // This is the default format
+    // Log format (this is the default format)
+    "log_format": "%TimeStamp% (%SourceLocation%) [%ThreadID%] %Channel%:%Severity% %Message%",
     "log_to_console": true,
-    "log_directory": "./clio_log",
+    // Clio logs to file in the specified directory only if "log_directory" is set
+    // "log_directory": "./clio_log",
     "log_rotation_size": 2048,
     "log_directory_max_size": 51200,
     "log_rotation_hour_interval": 12,
     "log_tag_style": "uint",
     "extractor_threads": 8,
     "read_only": false,
-    //"start_sequence": [integer] the ledger index to start from,
-    //"finish_sequence": [integer] the ledger index to finish at,
-    //"ssl_cert_file" : "/full/path/to/cert.file",
-    //"ssl_key_file" : "/full/path/to/key.file"
+    // "start_sequence": [integer] the ledger index to start from,
+    // "finish_sequence": [integer] the ledger index to finish at,
+    // "ssl_cert_file" : "/full/path/to/cert.file",
+    // "ssl_key_file" : "/full/path/to/key.file"
+    "api_version": {
+        "min": 1, // Minimum API version supported (could be 1 or 2)
+        "max": 2, // Maximum API version supported (could be 1 or 2, but >= min)
+        "default": 1 // Clio behaves the same as rippled by default
+    }
 }

examples/infrastructure/README.md

@@ -0,0 +1,25 @@
+# Example of clio monitoring infrastructure
+
+This directory contains an example of docker based infrastructure to collect and visualise metrics from clio.
+
+The structure of the directory:
+- `compose.yaml`
+   Docker-compose file with Prometheus and Grafana set up.
+- `prometheus.yaml`
+  Defines metrics collection from Clio and Prometheus itself.
+  Demonstrates how to setup Clio target and Clio's admin authorisation in Prometheus.
+- `grafana/clio_dashboard.json`
+  Json file containing preconfigured dashboard in Grafana format.
+- `grafana/dashboard_local.yaml`
+  Grafana configuration file defining the directory to search for dashboards json files.
+- `grafana/datasources.yaml`
+  Grafana configuration file defining Prometheus as a data source for Grafana.
+
+## How to try
+
+1. Make sure you have `docker` and `docker-compose` installed.
+2. Run `docker-compose up -d` from this directory. It will start docker containers with Prometheus and Grafana.
+3. Open [http://localhost:3000/dashboards](http://localhost:3000/dashboards). Grafana login `admin`, password `grafana`.
+There will be preconfigured Clio dashboard.
+
+If Clio is not running yet launch Clio to see metrics. Some of the metrics may appear only after requests to Clio.

examples/infrastructure/compose.yaml

@@ -0,0 +1,20 @@
+services:
+  prometheus:
+    image: prom/prometheus
+    ports:
+      - 9090:9090
+    volumes:
+      - ./prometheus.yaml:/etc/prometheus/prometheus.yml
+    command:
+      - '--config.file=/etc/prometheus/prometheus.yml'
+  grafana:
+    image: grafana/grafana
+    ports:
+      - 3000:3000
+    environment:
+      - GF_SECURITY_ADMIN_USER=admin
+      - GF_SECURITY_ADMIN_PASSWORD=grafana
+    volumes:
+      - ./grafana/datasources.yaml:/etc/grafana/provisioning/datasources/datasources.yaml
+      - ./grafana/dashboard_local.yaml:/etc/grafana/provisioning/dashboards/local.yaml
+      - ./grafana/clio_dashboard.json:/var/lib/grafana/dashboards/clio_dashboard.json

examples/infrastructure/grafana/dashboard_local.yaml

@@ -0,0 +1,23 @@
+apiVersion: 1
+
+providers:
+  - name: 'Clio dashboard'
+    # <int> Org id. Default to 1
+    orgId: 1
+    # <string> name of the dashboard folder.
+    folder: ''
+    # <string> folder UID. will be automatically generated if not specified
+    folderUid: ''
+    # <string> provider type. Default to 'file'
+    type: file
+    # <bool> disable dashboard deletion
+    disableDeletion: false
+    # <int> how often Grafana will scan for changed dashboards
+    updateIntervalSeconds: 10
+    # <bool> allow updating provisioned dashboards from the UI
+    allowUiUpdates: false
+    options:
+      # <string, required> path to dashboard files on disk. Required when using the 'file' type
+      path: /var/lib/grafana/dashboards
+      # <bool> use folder names from filesystem to create folders in Grafana
+      foldersFromFilesStructure: true

examples/infrastructure/grafana/datasources.yaml

@@ -0,0 +1,8 @@
+apiVersion: 1
+
+datasources:
+- name: Prometheus
+  type: prometheus
+  url: http://prometheus:9090
+  isDefault: true
+  access: proxy

examples/infrastructure/prometheus.yaml

@@ -0,0 +1,19 @@
+scrape_configs:
+- job_name: clio
+  scrape_interval: 5s
+  scrape_timeout: 5s
+  authorization:
+    type: Password
+    # sha256sum from password `xrp`
+    # use echo -n 'your_password' | shasum -a 256 to get hash
+    credentials: 0e1dcf1ff020cceabf8f4a60a32e814b5b46ee0bb8cd4af5c814e4071bd86a18
+  static_configs:
+  - targets:
+    -  host.docker.internal:51233
+- job_name: prometheus
+  honor_timestamps: true
+  scrape_interval: 15s
+  scrape_timeout: 10s
+  static_configs:
+  - targets:
+    - localhost:9090

metrics.py

@@ -1,183 +0,0 @@
-#!/usr/bin/python3
-import argparse
-
-from datetime import datetime
-
-def getTime(line):
-    bracketOpen = line.find("[")
-    bracketClose = line.find("]")
-    timestampSub = line[bracketOpen+1:bracketClose]
-    timestamp = datetime.strptime(timestampSub, '%Y-%m-%d %H:%M:%S.%f')
-    return timestamp.timestamp()
-
-def parseAccountTx(filename):
-
-
-    with open(filename) as f:
-        totalProcTime = 0.0
-        totalTxnTime = 0.0
-        numCalls = 0
-        for line in f:
-            if "executed stored_procedure" in line:
-                idx = line.find("in ")
-                idx = idx + 3
-                idx2 = line.find("num")
-                procTime = float(line[idx:idx2])
-                totalProcTime += procTime
-            if "fetchTransactions fetched" in line:
-                idx = line.find("took ")
-                idx = idx + 5
-                txnTime = float(line[idx:])
-                totalTxnTime += txnTime
-                numCalls = numCalls + 1
-        print(totalProcTime)
-        print(totalProcTime/numCalls)
-        print(totalTxnTime)
-        print(totalTxnTime/numCalls)
-            
-
-
-
-
-def parseLogs(filename, interval, minTxnCount = 0):
-
-    with open(filename) as f:
-
-        totalTime = 0
-        totalTxns = 0
-        totalObjs = 0
-        totalLoadTime = 0
-
-
-        start = 0
-        end = 0
-        totalLedgers = 0
-
-        intervalTime = 0
-        intervalTxns = 0
-        intervalObjs = 0
-        intervalLoadTime = 0
-
-        intervalStart = 0
-        intervalEnd = 0
-        intervalLedgers = 0
-        ledgersPerSecond = 0
-
-        print("ledgers, transactions, objects, loadTime, loadTime/ledger, ledgers/sec, txns/sec, objs/sec")
-        for line in f:
-            if "Load phase" in line:
-                sequenceIdx = line.find("Sequence : ")
-                hashIdx =  line.find(" Hash :")
-                sequence = line[sequenceIdx + len("Sequence : "):hashIdx]
-                txnCountSubstr = "txn count = "
-                objCountSubstr = ". object count = "
-                loadTimeSubstr = ". load time = "
-                txnsSubstr = ". load txns per second = "
-                objsSubstr = ". load objs per second = "
-                txnCountIdx = line.find(txnCountSubstr)
-                objCountIdx = line.find(objCountSubstr)
-                loadTimeIdx = line.find(loadTimeSubstr)
-                txnsIdx = line.find(txnsSubstr)
-                objsIdx = line.find(objsSubstr)
-                txnCount = line[txnCountIdx + len(txnCountSubstr):objCountIdx]
-                objCount = line[objCountIdx + len(objCountSubstr):loadTimeIdx]
-                loadTime = line[loadTimeIdx + len(loadTimeSubstr):txnsIdx]
-                txnsPerSecond = line[txnsIdx + len(txnsSubstr):objsIdx]
-                objsPerSecond = line[objsIdx + len(objsSubstr):-1]
-                if int(txnCount) >= minTxnCount:
-                    totalTime += float(loadTime);
-                    totalTxns += float(txnCount)
-                    totalObjs += float(objCount)
-                    intervalTime += float(loadTime)
-                    intervalTxns += float(txnCount)
-                    intervalObjs += float(objCount)
-
-                totalLoadTime += float(loadTime)
-                intervalLoadTime += float(loadTime)
-                
-
-                if start == 0:
-                    start = getTime(line)
-
-
-                prevEnd = end
-                end = getTime(line)
-
-                if intervalStart == 0:
-                    intervalStart = getTime(line)
-
-                intervalEnd = getTime(line)
-
-                totalLedgers+=1
-                intervalLedgers+=1
-                ledgersPerSecond = 0
-                if end != start:
-                    ledgersPerSecond = float(totalLedgers) / float((end - start))
-                intervalLedgersPerSecond = 0
-                if intervalEnd != intervalStart:
-                    intervalLedgersPerSecond = float(intervalLedgers) / float((intervalEnd - intervalStart))
-
-
-
-                if int(sequence) % interval == 0:
-
-                   # print("Sequence = " + sequence + " : [time, txCount, objCount, txPerSec, objsPerSec]")
-                   # print(loadTime + " , " 
-                   #     + txnCount + " , " 
-                   #     + objCount + " , " 
-                   #     + txnsPerSecond + " , " 
-                   #     + objsPerSecond)
-                   # print("Interval Aggregate ( " + str(interval) + " ) [ledgers, txns, objects, elapsedTime, ledgersPerSec, avgLoadTime, txPerSec, objsPerSec]: ")
-                    print(str(intervalLedgers) + " , " 
-                        + str(intervalTxns) + " , "
-                        + str(intervalObjs) + " , "
-                        + str(intervalLoadTime) + " , " 
-                        + str(intervalLoadTime/intervalLedgers) + " , " 
-                        + str(intervalLedgers/intervalLoadTime) + " , " 
-                        + str(intervalTxns/intervalLoadTime) + " , " 
-                        + str(intervalObjs/intervalLoadTime))
-                  #  print("Total Aggregate: [ledgers, txns, objects, elapsedTime, ledgersPerSec, avgLoadTime, txPerSec, objsPerSec]")
-                  #  print(str(totalLedgers) + " , " 
-                  #      + str(totalTxns) + " , "
-                  #      + str(totalObjs) + " , "
-                  #      + str(end-start) + " , " 
-                  #      + str(ledgersPerSecond) + " , " 
-                  #      + str(totalLoadTime/totalLedgers) + " , " 
-                  #      + str(totalTxns/totalTime) + " , " 
-                  #      + str(totalObjs/totalTime))
-                    if int(sequence) % interval == 0:
-                        intervalTime = 0
-                        intervalTxns = 0
-                        intervalObjs = 0
-                        intervalStart = 0
-                        intervalEnd = 0
-                        intervalLedgers = 0
-                        intervalLoadTime = 0
-        print("Total Aggregate: [ledgers, elapsedTime, ledgersPerSec, avgLoadTime, txPerSec, objsPerSec]")
-        print(totalLedgers)
-        print(totalLoadTime)
-        print(str(totalLedgers) + " : " 
-            + str(end-start) + " : " 
-            + str(ledgersPerSecond) + " : " 
-            + str(totalLoadTime/totalLedgers) + " : " 
-            + str(totalTxns/totalTime) + " : " 
-            + str(totalObjs/totalTime))
-
-
-    
-
-parser = argparse.ArgumentParser(description='parses logs')
-parser.add_argument("--filename")
-parser.add_argument("--interval",default=100000)
-parser.add_argument("--minTxnCount",default=0)
-parser.add_argument("--account_tx",default=False)
-
-args = parser.parse_args()
-
-def run(args):
-    if args.account_tx:
-        parseAccountTx(args.filename)
-    else:
-        parseLogs(args.filename, int(args.interval))
-
-run(args)

src/backend/BackendInterface.cpp

@@ -1,322 +0,0 @@
-//------------------------------------------------------------------------------
-/*
-    This file is part of clio: https://github.com/XRPLF/clio
-    Copyright (c) 2022, the clio developers.
-
-    Permission to use, copy, modify, and distribute this software for any
-    purpose with or without fee is hereby granted, provided that the above
-    copyright notice and this permission notice appear in all copies.
-
-    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
-    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
-    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
-    ANY  SPECIAL,  DIRECT,  INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
-    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
-    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
-    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
-*/
-//==============================================================================
-
-#include <ripple/protocol/Indexes.h>
-#include <ripple/protocol/STLedgerEntry.h>
-#include <backend/BackendInterface.h>
-#include <log/Logger.h>
-
-using namespace clio;
-
-// local to compilation unit loggers
-namespace {
-clio::Logger gLog{"Backend"};
-}  // namespace
-
-namespace Backend {
-bool
-BackendInterface::finishWrites(std::uint32_t const ledgerSequence)
-{
-    gLog.debug() << "Want finish writes for " << ledgerSequence;
-    auto commitRes = doFinishWrites();
-    if (commitRes)
-    {
-        gLog.debug() << "Successfully commited. Updating range now to " << ledgerSequence;
-        updateRange(ledgerSequence);
-    }
-    return commitRes;
-}
-void
-BackendInterface::writeLedgerObject(std::string&& key, std::uint32_t const seq, std::string&& blob)
-{
-    assert(key.size() == sizeof(ripple::uint256));
-    doWriteLedgerObject(std::move(key), seq, std::move(blob));
-}
-
-std::optional<LedgerRange>
-BackendInterface::hardFetchLedgerRangeNoThrow(boost::asio::yield_context& yield) const
-{
-    gLog.trace() << "called";
-    while (true)
-    {
-        try
-        {
-            return hardFetchLedgerRange(yield);
-        }
-        catch (DatabaseTimeout& t)
-        {
-            ;
-        }
-    }
-}
-
-std::optional<LedgerRange>
-BackendInterface::hardFetchLedgerRangeNoThrow() const
-{
-    gLog.trace() << "called";
-    return retryOnTimeout([&]() { return hardFetchLedgerRange(); });
-}
-
-// *** state data methods
-std::optional<Blob>
-BackendInterface::fetchLedgerObject(
-    ripple::uint256 const& key,
-    std::uint32_t const sequence,
-    boost::asio::yield_context& yield) const
-{
-    auto obj = cache_.get(key, sequence);
-    if (obj)
-    {
-        gLog.trace() << "Cache hit - " << ripple::strHex(key);
-        return *obj;
-    }
-    else
-    {
-        gLog.trace() << "Cache miss - " << ripple::strHex(key);
-        auto dbObj = doFetchLedgerObject(key, sequence, yield);
-        if (!dbObj)
-            gLog.trace() << "Missed cache and missed in db";
-        else
-            gLog.trace() << "Missed cache but found in db";
-        return dbObj;
-    }
-}
-
-std::vector<Blob>
-BackendInterface::fetchLedgerObjects(
-    std::vector<ripple::uint256> const& keys,
-    std::uint32_t const sequence,
-    boost::asio::yield_context& yield) const
-{
-    std::vector<Blob> results;
-    results.resize(keys.size());
-    std::vector<ripple::uint256> misses;
-    for (size_t i = 0; i < keys.size(); ++i)
-    {
-        auto obj = cache_.get(keys[i], sequence);
-        if (obj)
-            results[i] = *obj;
-        else
-            misses.push_back(keys[i]);
-    }
-    gLog.trace() << "Cache hits = " << keys.size() - misses.size() << " - cache misses = " << misses.size();
-
-    if (misses.size())
-    {
-        auto objs = doFetchLedgerObjects(misses, sequence, yield);
-        for (size_t i = 0, j = 0; i < results.size(); ++i)
-        {
-            if (results[i].size() == 0)
-            {
-                results[i] = objs[j];
-                ++j;
-            }
-        }
-    }
-
-    return results;
-}
-// Fetches the successor to key/index
-std::optional<ripple::uint256>
-BackendInterface::fetchSuccessorKey(
-    ripple::uint256 key,
-    std::uint32_t const ledgerSequence,
-    boost::asio::yield_context& yield) const
-{
-    auto succ = cache_.getSuccessor(key, ledgerSequence);
-    if (succ)
-        gLog.trace() << "Cache hit - " << ripple::strHex(key);
-    else
-        gLog.trace() << "Cache miss - " << ripple::strHex(key);
-    return succ ? succ->key : doFetchSuccessorKey(key, ledgerSequence, yield);
-}
-
-std::optional<LedgerObject>
-BackendInterface::fetchSuccessorObject(
-    ripple::uint256 key,
-    std::uint32_t const ledgerSequence,
-    boost::asio::yield_context& yield) const
-{
-    auto succ = fetchSuccessorKey(key, ledgerSequence, yield);
-    if (succ)
-    {
-        auto obj = fetchLedgerObject(*succ, ledgerSequence, yield);
-        if (!obj)
-            return {{*succ, {}}};
-
-        return {{*succ, *obj}};
-    }
-    return {};
-}
-
-BookOffersPage
-BackendInterface::fetchBookOffers(
-    ripple::uint256 const& book,
-    std::uint32_t const ledgerSequence,
-    std::uint32_t const limit,
-    boost::asio::yield_context& yield) const
-{
-    // TODO try to speed this up. This can take a few seconds. The goal is
-    // to get it down to a few hundred milliseconds.
-    BookOffersPage page;
-    const ripple::uint256 bookEnd = ripple::getQualityNext(book);
-    ripple::uint256 uTipIndex = book;
-    std::vector<ripple::uint256> keys;
-    auto getMillis = [](auto diff) { return std::chrono::duration_cast<std::chrono::milliseconds>(diff).count(); };
-    auto begin = std::chrono::system_clock::now();
-    std::uint32_t numSucc = 0;
-    std::uint32_t numPages = 0;
-    long succMillis = 0;
-    long pageMillis = 0;
-    while (keys.size() < limit)
-    {
-        auto mid1 = std::chrono::system_clock::now();
-        auto offerDir = fetchSuccessorObject(uTipIndex, ledgerSequence, yield);
-        auto mid2 = std::chrono::system_clock::now();
-        numSucc++;
-        succMillis += getMillis(mid2 - mid1);
-        if (!offerDir || offerDir->key >= bookEnd)
-        {
-            gLog.trace() << "offerDir.has_value() " << offerDir.has_value() << " breaking";
-            break;
-        }
-        uTipIndex = offerDir->key;
-        while (keys.size() < limit)
-        {
-            ++numPages;
-            ripple::STLedgerEntry sle{ripple::SerialIter{offerDir->blob.data(), offerDir->blob.size()}, offerDir->key};
-            auto indexes = sle.getFieldV256(ripple::sfIndexes);
-            keys.insert(keys.end(), indexes.begin(), indexes.end());
-            auto next = sle.getFieldU64(ripple::sfIndexNext);
-            if (!next)
-            {
-                gLog.trace() << "Next is empty. breaking";
-                break;
-            }
-            auto nextKey = ripple::keylet::page(uTipIndex, next);
-            auto nextDir = fetchLedgerObject(nextKey.key, ledgerSequence, yield);
-            assert(nextDir);
-            offerDir->blob = *nextDir;
-            offerDir->key = nextKey.key;
-        }
-        auto mid3 = std::chrono::system_clock::now();
-        pageMillis += getMillis(mid3 - mid2);
-    }
-    auto mid = std::chrono::system_clock::now();
-    auto objs = fetchLedgerObjects(keys, ledgerSequence, yield);
-    for (size_t i = 0; i < keys.size() && i < limit; ++i)
-    {
-        gLog.trace() << "Key = " << ripple::strHex(keys[i]) << " blob = " << ripple::strHex(objs[i])
-                     << " ledgerSequence = " << ledgerSequence;
-        assert(objs[i].size());
-        page.offers.push_back({keys[i], objs[i]});
-    }
-    auto end = std::chrono::system_clock::now();
-    gLog.debug() << "Fetching " << std::to_string(keys.size()) << " offers took "
-                 << std::to_string(getMillis(mid - begin)) << " milliseconds. Fetching next dir took "
-                 << std::to_string(succMillis) << " milliseonds. Fetched next dir " << std::to_string(numSucc)
-                 << " times"
-                 << " Fetching next page of dir took " << std::to_string(pageMillis) << " milliseconds"
-                 << ". num pages = " << std::to_string(numPages) << ". Fetching all objects took "
-                 << std::to_string(getMillis(end - mid))
-                 << " milliseconds. total time = " << std::to_string(getMillis(end - begin)) << " milliseconds"
-                 << " book = " << ripple::strHex(book);
-
-    return page;
-}
-
-LedgerPage
-BackendInterface::fetchLedgerPage(
-    std::optional<ripple::uint256> const& cursor,
-    std::uint32_t const ledgerSequence,
-    std::uint32_t const limit,
-    bool outOfOrder,
-    boost::asio::yield_context& yield) const
-{
-    LedgerPage page;
-
-    std::vector<ripple::uint256> keys;
-    bool reachedEnd = false;
-    while (keys.size() < limit && !reachedEnd)
-    {
-        ripple::uint256 const& curCursor = keys.size() ? keys.back() : cursor ? *cursor : firstKey;
-        std::uint32_t const seq = outOfOrder ? range->maxSequence : ledgerSequence;
-        auto succ = fetchSuccessorKey(curCursor, seq, yield);
-        if (!succ)
-            reachedEnd = true;
-        else
-            keys.push_back(std::move(*succ));
-    }
-
-    auto objects = fetchLedgerObjects(keys, ledgerSequence, yield);
-    for (size_t i = 0; i < objects.size(); ++i)
-    {
-        if (objects[i].size())
-            page.objects.push_back({std::move(keys[i]), std::move(objects[i])});
-        else if (!outOfOrder)
-        {
-            gLog.error() << "Deleted or non-existent object in successor table. key = " << ripple::strHex(keys[i])
-                         << " - seq = " << ledgerSequence;
-            std::stringstream msg;
-            for (size_t j = 0; j < objects.size(); ++j)
-            {
-                msg << " - " << ripple::strHex(keys[j]);
-            }
-            gLog.error() << msg.str();
-        }
-    }
-    if (keys.size() && !reachedEnd)
-        page.cursor = keys.back();
-
-    return page;
-}
-
-std::optional<ripple::Fees>
-BackendInterface::fetchFees(std::uint32_t const seq, boost::asio::yield_context& yield) const
-{
-    ripple::Fees fees;
-
-    auto key = ripple::keylet::fees().key;
-    auto bytes = fetchLedgerObject(key, seq, yield);
-
-    if (!bytes)
-    {
-        gLog.error() << "Could not find fees";
-        return {};
-    }
-
-    ripple::SerialIter it(bytes->data(), bytes->size());
-    ripple::SLE sle{it, key};
-
-    if (sle.getFieldIndex(ripple::sfBaseFee) != -1)
-        fees.base = sle.getFieldU64(ripple::sfBaseFee);
-
-    if (sle.getFieldIndex(ripple::sfReferenceFeeUnits) != -1)
-        fees.units = sle.getFieldU32(ripple::sfReferenceFeeUnits);
-
-    if (sle.getFieldIndex(ripple::sfReserveBase) != -1)
-        fees.reserve = sle.getFieldU32(ripple::sfReserveBase);
-
-    if (sle.getFieldIndex(ripple::sfReserveIncrement) != -1)
-        fees.increment = sle.getFieldU32(ripple::sfReserveIncrement);
-
-    return fees;
-}
-
-}  // namespace Backend

src/backend/BackendInterface.h

@@ -1,613 +0,0 @@
-//------------------------------------------------------------------------------
-/*
-    This file is part of clio: https://github.com/XRPLF/clio
-    Copyright (c) 2022, the clio developers.
-
-    Permission to use, copy, modify, and distribute this software for any
-    purpose with or without fee is hereby granted, provided that the above
-    copyright notice and this permission notice appear in all copies.
-
-    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
-    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
-    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
-    ANY  SPECIAL,  DIRECT,  INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
-    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
-    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
-    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
-*/
-//==============================================================================
-
-#pragma once
-
-#include <ripple/ledger/ReadView.h>
-#include <backend/DBHelpers.h>
-#include <backend/SimpleCache.h>
-#include <backend/Types.h>
-#include <config/Config.h>
-#include <log/Logger.h>
-
-#include <boost/asio/spawn.hpp>
-#include <boost/json.hpp>
-
-#include <thread>
-#include <type_traits>
-
-namespace Backend {
-
-/**
- * @brief Throws an error when database read time limit is exceeded.
- *
- * This class is throws an error when read time limit is exceeded but
- * is also paired with a separate class to retry the connection.
- */
-class DatabaseTimeout : public std::exception
-{
-public:
-    const char*
-    what() const throw() override
-    {
-        return "Database read timed out. Please retry the request";
-    }
-};
-
-/**
- * @brief Separate class that reattempts connection after time limit.
- *
- * @tparam F Represents a class of handlers for Cassandra database.
- * @param func Instance of Cassandra database handler class.
- * @param waitMs Is the arbitrary time limit of 500ms.
- * @return auto
- */
-template <class F>
-auto
-retryOnTimeout(F func, size_t waitMs = 500)
-{
-    static clio::Logger log{"Backend"};
-
-    while (true)
-    {
-        try
-        {
-            return func();
-        }
-        catch (DatabaseTimeout& t)
-        {
-            log.error() << "Database request timed out. Sleeping and retrying ... ";
-            std::this_thread::sleep_for(std::chrono::milliseconds(waitMs));
-        }
-    }
-}
-
-/**
- * @brief Passes in serialized handlers in an asynchronous fashion.
- *
- * Note that the synchronous auto passes handlers critical to supporting
- * the Clio backend. The coroutine types are checked if same/different.
- *
- * @tparam F Represents a class of handlers for Cassandra database.
- * @param f R-value instance of Cassandra handler class.
- * @return auto
- */
-template <class F>
-auto
-synchronous(F&& f)
-{
-    /** @brief Serialized handlers and their execution.
-     *
-     * The ctx class is converted into a serialized handler, also named
-     * ctx, and is used to pass a stream of data into the method.
-     */
-    boost::asio::io_context ctx;
-    boost::asio::io_context::strand strand(ctx);
-    std::optional<boost::asio::io_context::work> work;
-
-    /*! @brief Place the ctx within the vector of serialized handlers. */
-    work.emplace(ctx);
-
-    /**
-     * @brief If/else statements regarding coroutine type matching.
-     *
-     * R is the currently executing coroutine that is about to get passed.
-     * If corountine types do not match, the current one's type is stored.
-     */
-    using R = typename boost::result_of<F(boost::asio::yield_context&)>::type;
-    if constexpr (!std::is_same<R, void>::value)
-    {
-        /**
-         * @brief When the coroutine type is the same
-         *
-         * The spawn function enables programs to implement asynchronous logic
-         * in a synchronous manner. res stores the instance of the currently
-         * executing coroutine, yield. The different type is returned.
-         */
-        R res;
-        boost::asio::spawn(strand, [&f, &work, &res](boost::asio::yield_context yield) {
-            res = f(yield);
-            work.reset();
-        });
-
-        ctx.run();
-        return res;
-    }
-    else
-    {
-        /*! @brief When the corutine type is different, run as normal. */
-        boost::asio::spawn(strand, [&f, &work](boost::asio::yield_context yield) {
-            f(yield);
-            work.reset();
-        });
-
-        ctx.run();
-    }
-}
-
-/**
- * @brief Reestablishes synchronous connection on timeout.
- *
- * @tparam Represents a class of handlers for Cassandra database.
- * @param f R-value instance of Cassandra database handler class.
- * @return auto
- */
-template <class F>
-auto
-synchronousAndRetryOnTimeout(F&& f)
-{
-    return retryOnTimeout([&]() { return synchronous(f); });
-}
-
-/*! @brief Handles ledger and transaction backend data. */
-class BackendInterface
-{
-    /**
-     * @brief Shared mutexes and a cache for the interface.
-     *
-     * rngMutex is a shared mutex. Shared mutexes prevent shared data
-     * from being accessed by multiple threads and has two levels of
-     * access: shared and exclusive.
-     */
-protected:
-    mutable std::shared_mutex rngMtx_;
-    std::optional<LedgerRange> range;
-    SimpleCache cache_;
-
-    /**
-     * @brief Public read methods
-     *
-     * All of these reads methods can throw DatabaseTimeout. When writing
-     * code in an RPC handler, this exception does not need to be caught:
-     * when an RPC results in a timeout, an error is returned to the client.
-     */
-
-public:
-    BackendInterface() = default;
-    virtual ~BackendInterface() = default;
-
-    /*! @brief LEDGER METHODS */
-public:
-    /**
-     * @brief Cache that holds states of the ledger
-     *
-     * const version holds the original cache state; the other tracks
-     * historical changes.
-     *
-     * @return SimpleCache const&
-     */
-    SimpleCache const&
-    cache() const
-    {
-        return cache_;
-    }
-
-    SimpleCache&
-    cache()
-    {
-        return cache_;
-    }
-
-    /*! @brief Fetches a specific ledger by sequence number. */
-    virtual std::optional<ripple::LedgerInfo>
-    fetchLedgerBySequence(std::uint32_t const sequence, boost::asio::yield_context& yield) const = 0;
-
-    /*! @brief Fetches a specific ledger by hash. */
-    virtual std::optional<ripple::LedgerInfo>
-    fetchLedgerByHash(ripple::uint256 const& hash, boost::asio::yield_context& yield) const = 0;
-
-    /*! @brief Fetches the latest ledger sequence. */
-    virtual std::optional<std::uint32_t>
-    fetchLatestLedgerSequence(boost::asio::yield_context& yield) const = 0;
-
-    /*! @brief Fetches the current ledger range while locking that process */
-    std::optional<LedgerRange>
-    fetchLedgerRange() const
-    {
-        std::shared_lock lck(rngMtx_);
-        return range;
-    }
-
-    /**
-     * @brief Updates the range of sequences to be tracked.
-     *
-     * Function that continues updating the range sliding window or creates
-     * a new sliding window once the maxSequence limit has been reached.
-     *
-     * @param newMax Unsigned 32-bit integer representing new max of range.
-     */
-    void
-    updateRange(uint32_t newMax)
-    {
-        std::scoped_lock lck(rngMtx_);
-        assert(!range || newMax >= range->maxSequence);
-        if (!range)
-            range = {newMax, newMax};
-        else
-            range->maxSequence = newMax;
-    }
-
-    /**
-     * @brief Returns the fees for specific transactions.
-     *
-     * @param seq Unsigned 32-bit integer reprsenting sequence.
-     * @param yield The currently executing coroutine.
-     * @return std::optional<ripple::Fees>
-     */
-    std::optional<ripple::Fees>
-    fetchFees(std::uint32_t const seq, boost::asio::yield_context& yield) const;
-
-    /*! @brief TRANSACTION METHODS */
-    /**
-     * @brief Fetches a specific transaction.
-     *
-     * @param hash Unsigned 256-bit integer representing hash.
-     * @param yield The currently executing coroutine.
-     * @return std::optional<TransactionAndMetadata>
-     */
-    virtual std::optional<TransactionAndMetadata>
-    fetchTransaction(ripple::uint256 const& hash, boost::asio::yield_context& yield) const = 0;
-
-    /**
-     * @brief Fetches multiple transactions.
-     *
-     * @param hashes Unsigned integer value representing a hash.
-     * @param yield The currently executing coroutine.
-     * @return std::vector<TransactionAndMetadata>
-     */
-    virtual std::vector<TransactionAndMetadata>
-    fetchTransactions(std::vector<ripple::uint256> const& hashes, boost::asio::yield_context& yield) const = 0;
-
-    /**
-     * @brief Fetches all transactions for a specific account
-     *
-     * @param account A specific XRPL Account, speciifed by unique type
-     * accountID.
-     * @param limit Paging limit for how many transactions can be returned per
-     * page.
-     * @param forward Boolean whether paging happens forwards or backwards.
-     * @param cursor Important metadata returned every time paging occurs.
-     * @param yield Currently executing coroutine.
-     * @return TransactionsAndCursor
-     */
-    virtual TransactionsAndCursor
-    fetchAccountTransactions(
-        ripple::AccountID const& account,
-        std::uint32_t const limit,
-        bool forward,
-        std::optional<TransactionsCursor> const& cursor,
-        boost::asio::yield_context& yield) const = 0;
-
-    /**
-     * @brief Fetches all transactions from a specific ledger.
-     *
-     * @param ledgerSequence Unsigned 32-bit integer for latest total
-     * transactions.
-     * @param yield Currently executing coroutine.
-     * @return std::vector<TransactionAndMetadata>
-     */
-    virtual std::vector<TransactionAndMetadata>
-    fetchAllTransactionsInLedger(std::uint32_t const ledgerSequence, boost::asio::yield_context& yield) const = 0;
-
-    /**
-     * @brief Fetches all transaction hashes from a specific ledger.
-     *
-     * @param ledgerSequence Standard unsigned integer.
-     * @param yield Currently executing coroutine.
-     * @return std::vector<ripple::uint256>
-     */
-    virtual std::vector<ripple::uint256>
-    fetchAllTransactionHashesInLedger(std::uint32_t const ledgerSequence, boost::asio::yield_context& yield) const = 0;
-
-    /*! @brief NFT methods */
-    /**
-     * @brief Fetches a specific NFT
-     *
-     * @param tokenID Unsigned 256-bit integer.
-     * @param ledgerSequence Standard unsigned integer.
-     * @param yield Currently executing coroutine.
-     * @return std::optional<NFT>
-     */
-    virtual std::optional<NFT>
-    fetchNFT(ripple::uint256 const& tokenID, std::uint32_t const ledgerSequence, boost::asio::yield_context& yield)
-        const = 0;
-
-    /**
-     * @brief Fetches all transactions for a specific NFT.
-     *
-     * @param tokenID Unsigned 256-bit integer.
-     * @param limit Paging limit as to how many transactions return per page.
-     * @param forward Boolean whether paging happens forwards or backwards.
-     * @param cursorIn Represents transaction number and ledger sequence.
-     * @param yield Currently executing coroutine is passed in as input.
-     * @return TransactionsAndCursor
-     */
-    virtual TransactionsAndCursor
-    fetchNFTTransactions(
-        ripple::uint256 const& tokenID,
-        std::uint32_t const limit,
-        bool const forward,
-        std::optional<TransactionsCursor> const& cursorIn,
-        boost::asio::yield_context& yield) const = 0;
-
-    /*! @brief STATE DATA METHODS */
-    /**
-     * @brief Fetches a specific ledger object: vector of unsigned chars
-     *
-     * @param key Unsigned 256-bit integer.
-     * @param sequence Unsigned 32-bit integer.
-     * @param yield Currently executing coroutine.
-     * @return std::optional<Blob>
-     */
-    std::optional<Blob>
-    fetchLedgerObject(ripple::uint256 const& key, std::uint32_t const sequence, boost::asio::yield_context& yield)
-        const;
-
-    /**
-     * @brief Fetches all ledger objects: a vector of vectors of unsigned chars.
-     *
-     * @param keys Unsigned 256-bit integer.
-     * @param sequence Unsigned 32-bit integer.
-     * @param yield Currently executing coroutine.
-     * @return std::vector<Blob>
-     */
-    std::vector<Blob>
-    fetchLedgerObjects(
-        std::vector<ripple::uint256> const& keys,
-        std::uint32_t const sequence,
-        boost::asio::yield_context& yield) const;
-
-    /*! @brief Virtual function version of fetchLedgerObject */
-    virtual std::optional<Blob>
-    doFetchLedgerObject(ripple::uint256 const& key, std::uint32_t const sequence, boost::asio::yield_context& yield)
-        const = 0;
-
-    /*! @brief Virtual function version of fetchLedgerObjects */
-    virtual std::vector<Blob>
-    doFetchLedgerObjects(
-        std::vector<ripple::uint256> const& keys,
-        std::uint32_t const sequence,
-        boost::asio::yield_context& yield) const = 0;
-
-    /**
-     * @brief Returns the difference between ledgers: vector of objects
-     *
-     * Objects are made of a key value, vector of unsigned chars (blob),
-     * and a boolean detailing whether keys and blob match.
-     *
-     * @param ledgerSequence Standard unsigned integer.
-     * @param yield Currently executing coroutine.
-     * @return std::vector<LedgerObject>
-     */
-    virtual std::vector<LedgerObject>
-    fetchLedgerDiff(std::uint32_t const ledgerSequence, boost::asio::yield_context& yield) const = 0;
-
-    /**
-     * @brief Fetches a page of ledger objects, ordered by key/index.
-     *
-     * @param cursor Important metadata returned every time paging occurs.
-     * @param ledgerSequence Standard unsigned integer.
-     * @param limit Paging limit as to how many transactions returned per page.
-     * @param outOfOrder Boolean on whether ledger page is out of order.
-     * @param yield Currently executing coroutine.
-     * @return LedgerPage
-     */
-    LedgerPage
-    fetchLedgerPage(
-        std::optional<ripple::uint256> const& cursor,
-        std::uint32_t const ledgerSequence,
-        std::uint32_t const limit,
-        bool outOfOrder,
-        boost::asio::yield_context& yield) const;
-
-    /*! @brief Fetches successor object from key/index. */
-    std::optional<LedgerObject>
-    fetchSuccessorObject(ripple::uint256 key, std::uint32_t const ledgerSequence, boost::asio::yield_context& yield)
-        const;
-
-    /*! @brief Fetches successor key from key/index. */
-    std::optional<ripple::uint256>
-    fetchSuccessorKey(ripple::uint256 key, std::uint32_t const ledgerSequence, boost::asio::yield_context& yield) const;
-
-    /*! @brief Virtual function version of fetchSuccessorKey. */
-    virtual std::optional<ripple::uint256>
-    doFetchSuccessorKey(ripple::uint256 key, std::uint32_t const ledgerSequence, boost::asio::yield_context& yield)
-        const = 0;
-
-    /**
-     * @brief Fetches book offers.
-     *
-     * @param book Unsigned 256-bit integer.
-     * @param ledgerSequence Standard unsigned integer.
-     * @param limit Pagaing limit as to how many transactions returned per page.
-     * @param cursor Important metadata returned every time paging occurs.
-     * @param yield Currently executing coroutine.
-     * @return BookOffersPage
-     */
-    BookOffersPage
-    fetchBookOffers(
-        ripple::uint256 const& book,
-        std::uint32_t const ledgerSequence,
-        std::uint32_t const limit,
-        boost::asio::yield_context& yield) const;
-
-    /**
-     * @brief Returns a ledger range
-     *
-     * Ledger range is a struct of min and max sequence numbers). Due to
-     * the use of [&], which denotes a special case of a lambda expression
-     * where values found outside the scope are passed by reference, wrt the
-     * currently executing coroutine.
-     *
-     * @return std::optional<LedgerRange>
-     */
-    std::optional<LedgerRange>
-    hardFetchLedgerRange() const
-    {
-        return synchronous([&](boost::asio::yield_context yield) { return hardFetchLedgerRange(yield); });
-    }
-
-    /*! @brief Virtual function equivalent of hardFetchLedgerRange. */
-    virtual std::optional<LedgerRange>
-    hardFetchLedgerRange(boost::asio::yield_context& yield) const = 0;
-
-    /*! @brief Fetches ledger range but doesn't throw timeout. Use with care. */
-    std::optional<LedgerRange>
-    hardFetchLedgerRangeNoThrow() const;
-    /*! @brief Fetches ledger range but doesn't throw timeout. Use with care. */
-    std::optional<LedgerRange>
-    hardFetchLedgerRangeNoThrow(boost::asio::yield_context& yield) const;
-
-    /**
-     * @brief Writes to a specific ledger.
-     *
-     * @param ledgerInfo Const on ledger information.
-     * @param ledgerHeader r-value string representing ledger header.
-     */
-    virtual void
-    writeLedger(ripple::LedgerInfo const& ledgerInfo, std::string&& ledgerHeader) = 0;
-
-    /**
-     * @brief Writes a new ledger object.
-     *
-     * The key and blob are r-value references and do NOT have memory addresses.
-     *
-     * @param key String represented as an r-value.
-     * @param seq Unsigned integer representing a sequence.
-     * @param blob r-value vector of unsigned characters (blob).
-     */
-    virtual void
-    writeLedgerObject(std::string&& key, std::uint32_t const seq, std::string&& blob);
-
-    /**
-     * @brief Writes a new transaction.
-     *
-     * @param hash r-value reference. No memory address.
-     * @param seq Unsigned 32-bit integer.
-     * @param date Unsigned 32-bit integer.
-     * @param transaction r-value reference. No memory address.
-     * @param metadata r-value refrence. No memory address.
-     */
-    virtual void
-    writeTransaction(
-        std::string&& hash,
-        std::uint32_t const seq,
-        std::uint32_t const date,
-        std::string&& transaction,
-        std::string&& metadata) = 0;
-
-    /**
-     * @brief Write a new NFT.
-     *
-     * @param data Passed in as an r-value reference.
-     */
-    virtual void
-    writeNFTs(std::vector<NFTsData>&& data) = 0;
-
-    /**
-     * @brief Write a new set of account transactions.
-     *
-     * @param data Passed in as an r-value reference.
-     */
-    virtual void
-    writeAccountTransactions(std::vector<AccountTransactionsData>&& data) = 0;
-
-    /**
-     * @brief Write a new transaction for a specific NFT.
-     *
-     * @param data Passed in as an r-value reference.
-     */
-    virtual void
-    writeNFTTransactions(std::vector<NFTTransactionsData>&& data) = 0;
-
-    /**
-     * @brief Write a new successor.
-     *
-     * @param key Passed in as an r-value reference.
-     * @param seq Unsigned 32-bit integer.
-     * @param successor Passed in as an r-value reference.
-     */
-    virtual void
-    writeSuccessor(std::string&& key, std::uint32_t const seq, std::string&& successor) = 0;
-
-    /*! @brief Tells database we will write data for a specific ledger. */
-    virtual void
-    startWrites() const = 0;
-
-    /**
-     * @brief Tells database we finished writing all data for a specific ledger.
-     *
-     * TODO: change the return value to represent different results:
-     * Committed, write conflict, errored, successful but not committed
-     *
-     * @param ledgerSequence Const unsigned 32-bit integer on ledger sequence.
-     * @return true
-     * @return false
-     */
-    bool
-    finishWrites(std::uint32_t const ledgerSequence);
-
-    /**
-     * @brief Selectively delets parts of the database.
-     *
-     * @param numLedgersToKeep Unsigned 32-bit integer on number of ledgers to
-     * keep.
-     * @param yield Currently executing coroutine.
-     * @return true
-     * @return false
-     */
-    virtual bool
-    doOnlineDelete(std::uint32_t numLedgersToKeep, boost::asio::yield_context& yield) const = 0;
-
-    /**
-     * @brief Opens the database
-     *
-     * Open the database. Set up all of the necessary objects and
-     * datastructures. After this call completes, the database is
-     * ready for use.
-     *
-     * @param readOnly Boolean whether ledger is read only.
-     */
-    virtual void
-    open(bool readOnly) = 0;
-
-    /*! @brief Closes the database, releasing any resources. */
-    virtual void
-    close(){};
-
-    virtual bool
-    isTooBusy() const = 0;
-
-private:
-    /**
-     * @brief Private helper method to write ledger object
-     *
-     * @param key r-value string representing key.
-     * @param seq Unsigned 32-bit integer representing sequence.
-     * @param blob r-value vector of unsigned chars.
-     */
-    virtual void
-    doWriteLedgerObject(std::string&& key, std::uint32_t const seq, std::string&& blob) = 0;
-
-    virtual bool
-    doFinishWrites() = 0;
-};
-
-}  // namespace Backend
-using BackendInterface = Backend::BackendInterface;

src/backend/SimpleCache.h

@@ -1,95 +0,0 @@
-//------------------------------------------------------------------------------
-/*
-    This file is part of clio: https://github.com/XRPLF/clio
-    Copyright (c) 2022, the clio developers.
-
-    Permission to use, copy, modify, and distribute this software for any
-    purpose with or without fee is hereby granted, provided that the above
-    copyright notice and this permission notice appear in all copies.
-
-    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
-    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
-    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
-    ANY  SPECIAL,  DIRECT,  INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
-    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
-    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
-    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
-*/
-//==============================================================================
-
-#pragma once
-
-#include <ripple/basics/base_uint.h>
-#include <ripple/basics/hardened_hash.h>
-#include <backend/Types.h>
-#include <map>
-#include <mutex>
-#include <shared_mutex>
-#include <utility>
-#include <vector>
-namespace Backend {
-class SimpleCache
-{
-    struct CacheEntry
-    {
-        uint32_t seq = 0;
-        Blob blob;
-    };
-
-    // counters for fetchLedgerObject(s) hit rate
-    mutable std::atomic_uint32_t objectReqCounter_ = 0;
-    mutable std::atomic_uint32_t objectHitCounter_ = 0;
-    // counters for fetchSuccessorKey hit rate
-    mutable std::atomic_uint32_t successorReqCounter_ = 0;
-    mutable std::atomic_uint32_t successorHitCounter_ = 0;
-
-    std::map<ripple::uint256, CacheEntry> map_;
-    mutable std::shared_mutex mtx_;
-    uint32_t latestSeq_ = 0;
-    std::atomic_bool full_ = false;
-    std::atomic_bool disabled_ = false;
-    // temporary set to prevent background thread from writing already deleted
-    // data. not used when cache is full
-    std::unordered_set<ripple::uint256, ripple::hardened_hash<>> deletes_;
-
-public:
-    // Update the cache with new ledger objects
-    // set isBackground to true when writing old data from a background thread
-    void
-    update(std::vector<LedgerObject> const& blobs, uint32_t seq, bool isBackground = false);
-
-    std::optional<Blob>
-    get(ripple::uint256 const& key, uint32_t seq) const;
-
-    // always returns empty optional if isFull() is false
-    std::optional<LedgerObject>
-    getSuccessor(ripple::uint256 const& key, uint32_t seq) const;
-
-    // always returns empty optional if isFull() is false
-    std::optional<LedgerObject>
-    getPredecessor(ripple::uint256 const& key, uint32_t seq) const;
-
-    void
-    setDisabled();
-
-    void
-    setFull();
-
-    uint32_t
-    latestLedgerSequence() const;
-
-    // whether the cache has all data for the most recent ledger
-    bool
-    isFull() const;
-
-    size_t
-    size() const;
-
-    float
-    getObjectHitRate() const;
-
-    float
-    getSuccessorHitRate() const;
-};
-
-}  // namespace Backend

src/backend/cassandra/Concepts.h

@@ -1,79 +0,0 @@
-//------------------------------------------------------------------------------
-/*
-    This file is part of clio: https://github.com/XRPLF/clio
-    Copyright (c) 2023, the clio developers.
-
-    Permission to use, copy, modify, and distribute this software for any
-    purpose with or without fee is hereby granted, provided that the above
-    copyright notice and this permission notice appear in all copies.
-
-    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
-    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
-    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
-    ANY  SPECIAL,  DIRECT,  INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
-    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
-    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
-    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
-*/
-//==============================================================================
-
-#pragma once
-
-#include <backend/cassandra/Types.h>
-
-#include <boost/asio/spawn.hpp>
-
-#include <chrono>
-#include <concepts>
-#include <optional>
-#include <string>
-
-namespace Backend::Cassandra {
-
-// clang-format off
-template <typename T>
-concept SomeSettingsProvider = requires(T a) {
-    { a.getSettings() } -> std::same_as<Settings>;
-    { a.getKeyspace() } -> std::same_as<std::string>;
-    { a.getTablePrefix() } -> std::same_as<std::optional<std::string>>;
-    { a.getReplicationFactor() } -> std::same_as<uint16_t>;
-    { a.getTtl() } -> std::same_as<uint16_t>;
-};
-// clang-format on
-
-// clang-format off
-template <typename T>
-concept SomeExecutionStrategy = requires(
-    T a, 
-    Settings settings, 
-    Handle handle, 
-    Statement statement, 
-    std::vector<Statement> statements,
-    PreparedStatement prepared,
-    boost::asio::yield_context token
-) {
-    { T(settings, handle) };
-    { a.sync() } -> std::same_as<void>;
-    { a.isTooBusy() } -> std::same_as<bool>;
-    { a.writeSync(statement) } -> std::same_as<ResultOrError>;
-    { a.writeSync(prepared) } -> std::same_as<ResultOrError>;
-    { a.write(prepared) } -> std::same_as<void>;
-    { a.write(std::move(statements)) } -> std::same_as<void>;
-    { a.read(token, prepared) } -> std::same_as<ResultOrError>;
-    { a.read(token, statement) } -> std::same_as<ResultOrError>;
-    { a.read(token, statements) } -> std::same_as<ResultOrError>;
-    { a.readEach(token, statements) } -> std::same_as<std::vector<Result>>;
-};
-// clang-format on
-
-// clang-format off
-template <typename T>
-concept SomeRetryPolicy = requires(T a, boost::asio::io_context ioc, CassandraError err, uint32_t attempt) {
-    { T(ioc) };
-    { a.shouldRetry(err) } -> std::same_as<bool>;
-    { a.retry([](){}) } -> std::same_as<void>;
-    { a.calculateDelay(attempt) } -> std::same_as<std::chrono::milliseconds>;
-};
-// clang-format on
-
-}  // namespace Backend::Cassandra

src/backend/cassandra/impl/Cluster.h

@@ -1,99 +0,0 @@
-//------------------------------------------------------------------------------
-/*
-    This file is part of clio: https://github.com/XRPLF/clio
-    Copyright (c) 2023, the clio developers.
-
-    Permission to use, copy, modify, and distribute this software for any
-    purpose with or without fee is hereby granted, provided that the above
-    copyright notice and this permission notice appear in all copies.
-
-    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
-    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
-    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
-    ANY  SPECIAL,  DIRECT,  INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
-    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
-    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
-    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
-*/
-//==============================================================================
-
-#pragma once
-
-#include <backend/cassandra/impl/ManagedObject.h>
-#include <log/Logger.h>
-
-#include <cassandra.h>
-
-#include <chrono>
-#include <optional>
-#include <string>
-#include <string_view>
-#include <thread>
-#include <variant>
-
-namespace Backend::Cassandra::detail {
-
-struct Settings
-{
-    struct ContactPoints
-    {
-        std::string contactPoints = "127.0.0.1";  // defaults to localhost
-        std::optional<uint16_t> port;
-    };
-
-    struct SecureConnectionBundle
-    {
-        std::string bundle;  // no meaningful default
-    };
-
-    bool enableLog = false;
-    std::chrono::milliseconds connectionTimeout = std::chrono::milliseconds{10000};
-    std::chrono::milliseconds requestTimeout = std::chrono::milliseconds{0};  // no timeout at all
-    std::variant<ContactPoints, SecureConnectionBundle> connectionInfo = ContactPoints{};
-    uint32_t threads = std::thread::hardware_concurrency();
-    uint32_t maxWriteRequestsOutstanding = 10'000;
-    uint32_t maxReadRequestsOutstanding = 100'000;
-    std::optional<std::string> certificate;  // ssl context
-    std::optional<std::string> username;
-    std::optional<std::string> password;
-
-    Settings
-    withContactPoints(std::string_view contactPoints)
-    {
-        auto tmp = *this;
-        tmp.connectionInfo = ContactPoints{std::string{contactPoints}};
-        return tmp;
-    }
-
-    static Settings
-    defaultSettings()
-    {
-        return Settings();
-    }
-};
-
-class Cluster : public ManagedObject<CassCluster>
-{
-    clio::Logger log_{"Backend"};
-
-public:
-    Cluster(Settings const& settings);
-
-private:
-    void
-    setupConnection(Settings const& settings);
-
-    void
-    setupContactPoints(Settings::ContactPoints const& points);
-
-    void
-    setupSecureBundle(Settings::SecureConnectionBundle const& bundle);
-
-    void
-    setupCertificate(Settings const& settings);
-
-    void
-    setupCredentials(Settings const& settings);
-};
-
-}  // namespace Backend::Cassandra::detail

src/backend/cassandra/impl/ExecutionStrategy.h

@@ -1,443 +0,0 @@
-//------------------------------------------------------------------------------
-/*
-    This file is part of clio: https://github.com/XRPLF/clio
-    Copyright (c) 2023, the clio developers.
-
-    Permission to use, copy, modify, and distribute this software for any
-    purpose with or without fee is hereby granted, provided that the above
-    copyright notice and this permission notice appear in all copies.
-
-    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
-    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
-    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
-    ANY  SPECIAL,  DIRECT,  INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
-    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
-    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
-    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
-*/
-//==============================================================================
-
-#pragma once
-
-#include <backend/cassandra/Handle.h>
-#include <backend/cassandra/Types.h>
-#include <backend/cassandra/impl/AsyncExecutor.h>
-#include <log/Logger.h>
-#include <util/Expected.h>
-
-#include <boost/asio/async_result.hpp>
-#include <boost/asio/spawn.hpp>
-
-#include <atomic>
-#include <condition_variable>
-#include <functional>
-#include <memory>
-#include <mutex>
-#include <optional>
-#include <thread>
-
-namespace Backend::Cassandra::detail {
-
-/**
- * @brief Implements async and sync querying against the cassandra DB with
- * support for throttling.
- *
- * Note: A lot of the code that uses yield is repeated below. This is ok for now
- * because we are hopefully going to be getting rid of it entirely later on.
- */
-template <typename HandleType = Handle>
-class DefaultExecutionStrategy
-{
-    clio::Logger log_{"Backend"};
-
-    std::uint32_t maxWriteRequestsOutstanding_;
-    std::atomic_uint32_t numWriteRequestsOutstanding_ = 0;
-
-    std::uint32_t maxReadRequestsOutstanding_;
-    std::atomic_uint32_t numReadRequestsOutstanding_ = 0;
-
-    std::mutex throttleMutex_;
-    std::condition_variable throttleCv_;
-
-    std::mutex syncMutex_;
-    std::condition_variable syncCv_;
-
-    boost::asio::io_context ioc_;
-    std::optional<boost::asio::io_service::work> work_;
-
-    std::reference_wrapper<HandleType const> handle_;
-    std::thread thread_;
-
-public:
-    using ResultOrErrorType = typename HandleType::ResultOrErrorType;
-    using StatementType = typename HandleType::StatementType;
-    using PreparedStatementType = typename HandleType::PreparedStatementType;
-    using FutureType = typename HandleType::FutureType;
-    using FutureWithCallbackType = typename HandleType::FutureWithCallbackType;
-    using ResultType = typename HandleType::ResultType;
-
-    using CompletionTokenType = boost::asio::yield_context;
-    using FunctionType = void(boost::system::error_code);
-    using AsyncResultType = boost::asio::async_result<CompletionTokenType, FunctionType>;
-    using HandlerType = typename AsyncResultType::completion_handler_type;
-
-    DefaultExecutionStrategy(Settings settings, HandleType const& handle)
-        : maxWriteRequestsOutstanding_{settings.maxWriteRequestsOutstanding}
-        , maxReadRequestsOutstanding_{settings.maxReadRequestsOutstanding}
-        , work_{ioc_}
-        , handle_{std::cref(handle)}
-        , thread_{[this]() { ioc_.run(); }}
-    {
-        log_.info() << "Max write requests outstanding is " << maxWriteRequestsOutstanding_
-                    << "; Max read requests outstanding is " << maxReadRequestsOutstanding_;
-    }
-
-    ~DefaultExecutionStrategy()
-    {
-        work_.reset();
-        ioc_.stop();
-        thread_.join();
-    }
-
-    /**
-     * @brief Wait for all async writes to finish before unblocking
-     */
-    void
-    sync()
-    {
-        log_.debug() << "Waiting to sync all writes...";
-        std::unique_lock<std::mutex> lck(syncMutex_);
-        syncCv_.wait(lck, [this]() { return finishedAllWriteRequests(); });
-        log_.debug() << "Sync done.";
-    }
-
-    bool
-    isTooBusy() const
-    {
-        return numReadRequestsOutstanding_ >= maxReadRequestsOutstanding_;
-    }
-
-    /**
-     * @brief Blocking query execution used for writing data
-     *
-     * Retries forever sleeping for 5 milliseconds between attempts.
-     */
-    ResultOrErrorType
-    writeSync(StatementType const& statement)
-    {
-        while (true)
-        {
-            if (auto res = handle_.get().execute(statement); res)
-            {
-                return res;
-            }
-            else
-            {
-                log_.warn() << "Cassandra sync write error, retrying: " << res.error();
-                std::this_thread::sleep_for(std::chrono::milliseconds(5));
-            }
-        }
-    }
-
-    /**
-     * @brief Blocking query execution used for writing data
-     *
-     * Retries forever sleeping for 5 milliseconds between attempts.
-     */
-    template <typename... Args>
-    ResultOrErrorType
-    writeSync(PreparedStatementType const& preparedStatement, Args&&... args)
-    {
-        return writeSync(preparedStatement.bind(std::forward<Args>(args)...));
-    }
-
-    /**
-     * @brief Non-blocking query execution used for writing data
-     *
-     * Retries forever with retry policy specified by @ref AsyncExecutor
-     *
-     * @param prepradeStatement Statement to prepare and execute
-     * @param args Args to bind to the prepared statement
-     * @throw DatabaseTimeout on timeout
-     */
-    template <typename... Args>
-    void
-    write(PreparedStatementType const& preparedStatement, Args&&... args)
-    {
-        auto statement = preparedStatement.bind(std::forward<Args>(args)...);
-        incrementOutstandingRequestCount();
-
-        // Note: lifetime is controlled by std::shared_from_this internally
-        AsyncExecutor<std::decay_t<decltype(statement)>, HandleType>::run(
-            ioc_, handle_, std::move(statement), [this](auto const&) { decrementOutstandingRequestCount(); });
-    }
-
-    /**
-     * @brief Non-blocking batched query execution used for writing data
-     *
-     * Retries forever with retry policy specified by @ref AsyncExecutor.
-     *
-     * @param statements Vector of statements to execute as a batch
-     * @throw DatabaseTimeout on timeout
-     */
-    void
-    write(std::vector<StatementType>&& statements)
-    {
-        if (statements.empty())
-            return;
-
-        incrementOutstandingRequestCount();
-
-        // Note: lifetime is controlled by std::shared_from_this internally
-        AsyncExecutor<std::decay_t<decltype(statements)>, HandleType>::run(
-            ioc_, handle_, std::move(statements), [this](auto const&) { decrementOutstandingRequestCount(); });
-    }
-
-    /**
-     * @brief Coroutine-based query execution used for reading data.
-     *
-     * Retries forever until successful or throws an exception on timeout.
-     *
-     * @param token Completion token (yield_context)
-     * @param prepradeStatement Statement to prepare and execute
-     * @param args Args to bind to the prepared statement
-     * @throw DatabaseTimeout on timeout
-     * @return ResultType or error wrapped in Expected
-     */
-    template <typename... Args>
-    [[maybe_unused]] ResultOrErrorType
-    read(CompletionTokenType token, PreparedStatementType const& preparedStatement, Args&&... args)
-    {
-        return read(token, preparedStatement.bind(std::forward<Args>(args)...));
-    }
-
-    /**
-     * @brief Coroutine-based query execution used for reading data.
-     *
-     * Retries forever until successful or throws an exception on timeout.
-     *
-     * @param token Completion token (yield_context)
-     * @param statements Statements to execute in a batch
-     * @throw DatabaseTimeout on timeout
-     * @return ResultType or error wrapped in Expected
-     */
-    [[maybe_unused]] ResultOrErrorType
-    read(CompletionTokenType token, std::vector<StatementType> const& statements)
-    {
-        auto handler = HandlerType{token};
-        auto result = AsyncResultType{handler};
-        auto const numStatements = statements.size();
-
-        // todo: perhaps use policy instead
-        while (true)
-        {
-            numReadRequestsOutstanding_ += numStatements;
-
-            auto const future = handle_.get().asyncExecute(statements, [handler](auto&&) mutable {
-                boost::asio::post(boost::asio::get_associated_executor(handler), [handler]() mutable {
-                    handler(boost::system::error_code{});
-                });
-            });
-
-            // suspend coroutine until completion handler is called
-            result.get();
-
-            numReadRequestsOutstanding_ -= numStatements;
-
-            // it's safe to call blocking get on future here as we already
-            // waited for the coroutine to resume above.
-            if (auto res = future.get(); res)
-            {
-                return res;
-            }
-            else
-            {
-                log_.error() << "Failed batch read in coroutine: " << res.error();
-                throwErrorIfNeeded(res.error());
-            }
-        }
-    }
-
-    /**
-     * @brief Coroutine-based query execution used for reading data.
-     *
-     * Retries forever until successful or throws an exception on timeout.
-     *
-     * @param token Completion token (yield_context)
-     * @param statement Statement to execute
-     * @throw DatabaseTimeout on timeout
-     * @return ResultType or error wrapped in Expected
-     */
-    [[maybe_unused]] ResultOrErrorType
-    read(CompletionTokenType token, StatementType const& statement)
-    {
-        auto handler = HandlerType{token};
-        auto result = AsyncResultType{handler};
-
-        // todo: perhaps use policy instead
-        while (true)
-        {
-            ++numReadRequestsOutstanding_;
-
-            auto const future = handle_.get().asyncExecute(statement, [handler](auto const&) mutable {
-                boost::asio::post(boost::asio::get_associated_executor(handler), [handler]() mutable {
-                    handler(boost::system::error_code{});
-                });
-            });
-
-            // suspend coroutine until completion handler is called
-            result.get();
-
-            --numReadRequestsOutstanding_;
-
-            // it's safe to call blocking get on future here as we already
-            // waited for the coroutine to resume above.
-            if (auto res = future.get(); res)
-            {
-                return res;
-            }
-            else
-            {
-                log_.error() << "Failed read in coroutine: " << res.error();
-                throwErrorIfNeeded(res.error());
-            }
-        }
-    }
-
-    /**
-     * @brief Coroutine-based query execution used for reading data.
-     *
-     * Attempts to execute each statement. On any error the whole vector will be
-     * discarded and exception will be thrown.
-     *
-     * @param token Completion token (yield_context)
-     * @param statements Statements to execute
-     * @throw DatabaseTimeout on db error
-     * @return Vector of results
-     */
-    std::vector<ResultType>
-    readEach(CompletionTokenType token, std::vector<StatementType> const& statements)
-    {
-        auto handler = HandlerType{token};
-        auto result = AsyncResultType{handler};
-
-        std::atomic_bool hadError = false;
-        std::atomic_int numOutstanding = statements.size();
-        numReadRequestsOutstanding_ += statements.size();
-
-        auto futures = std::vector<FutureWithCallbackType>{};
-        futures.reserve(numOutstanding);
-
-        // used as the handler for each async statement individually
-        auto executionHandler = [handler, &hadError, &numOutstanding](auto const& res) mutable {
-            if (not res)
-                hadError = true;
-
-            // when all async operations complete unblock the result
-            if (--numOutstanding == 0)
-                boost::asio::post(boost::asio::get_associated_executor(handler), [handler]() mutable {
-                    handler(boost::system::error_code{});
-                });
-        };
-
-        std::transform(
-            std::cbegin(statements),
-            std::cend(statements),
-            std::back_inserter(futures),
-            [this, &executionHandler](auto const& statement) {
-                return handle_.get().asyncExecute(statement, executionHandler);
-            });
-
-        // suspend coroutine until completion handler is called
-        result.get();
-
-        numReadRequestsOutstanding_ -= statements.size();
-
-        if (hadError)
-            throw DatabaseTimeout{};
-
-        std::vector<ResultType> results;
-        results.reserve(futures.size());
-
-        // it's safe to call blocking get on futures here as we already
-        // waited for the coroutine to resume above.
-        std::transform(
-            std::make_move_iterator(std::begin(futures)),
-            std::make_move_iterator(std::end(futures)),
-            std::back_inserter(results),
-            [](auto&& future) {
-                auto entry = future.get();
-                auto&& res = entry.value();
-                return std::move(res);
-            });
-
-        assert(futures.size() == statements.size());
-        assert(results.size() == statements.size());
-        return results;
-    }
-
-private:
-    void
-    incrementOutstandingRequestCount()
-    {
-        {
-            std::unique_lock<std::mutex> lck(throttleMutex_);
-            if (!canAddWriteRequest())
-            {
-                log_.trace() << "Max outstanding requests reached. "
-                             << "Waiting for other requests to finish";
-                throttleCv_.wait(lck, [this]() { return canAddWriteRequest(); });
-            }
-        }
-        ++numWriteRequestsOutstanding_;
-    }
-
-    void
-    decrementOutstandingRequestCount()
-    {
-        // sanity check
-        if (numWriteRequestsOutstanding_ == 0)
-        {
-            assert(false);
-            throw std::runtime_error("decrementing num outstanding below 0");
-        }
-        size_t cur = (--numWriteRequestsOutstanding_);
-        {
-            // mutex lock required to prevent race condition around spurious
-            // wakeup
-            std::lock_guard lck(throttleMutex_);
-            throttleCv_.notify_one();
-        }
-        if (cur == 0)
-        {
-            // mutex lock required to prevent race condition around spurious
-            // wakeup
-            std::lock_guard lck(syncMutex_);
-            syncCv_.notify_one();
-        }
-    }
-
-    bool
-    canAddWriteRequest() const
-    {
-        return numWriteRequestsOutstanding_ < maxWriteRequestsOutstanding_;
-    }
-
-    bool
-    finishedAllWriteRequests() const
-    {
-        return numWriteRequestsOutstanding_ == 0;
-    }
-
-    void
-    throwErrorIfNeeded(CassandraError err) const
-    {
-        if (err.isTimeout())
-            throw DatabaseTimeout();
-
-        if (err.isInvalidQuery())
-            throw std::runtime_error("Invalid query");
-    }
-};
-
-}  // namespace Backend::Cassandra::detail

src/data/BackendCounters.cpp

@@ -0,0 +1,240 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of clio: https://github.com/XRPLF/clio
+    Copyright (c) 2023, the clio developers.
+
+    Permission to use, copy, modify, and distribute this software for any
+    purpose with or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL,  DIRECT,  INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+
+#include "data/BackendCounters.hpp"
+
+#include "util/Assert.hpp"
+#include "util/prometheus/Label.hpp"
+#include "util/prometheus/Prometheus.hpp"
+
+#include <boost/json/object.hpp>
+
+#include <chrono>
+#include <cstdint>
+#include <memory>
+#include <string>
+#include <utility>
+#include <vector>
+
+namespace data {
+
+namespace {
+
+std::vector<std::int64_t> const histogramBuckets{1, 2, 5, 10, 20, 50, 100, 200, 500, 700, 1000};
+
+std::int64_t
+durationInMillisecondsSince(std::chrono::steady_clock::time_point const startTime)
+{
+    return std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::steady_clock::now() - startTime).count();
+}
+
+}  // namespace
+
+using namespace util::prometheus;
+
+BackendCounters::BackendCounters()
+    : tooBusyCounter_(PrometheusService::counterInt(
+          "backend_too_busy_total_number",
+          Labels(),
+          "The total number of times the backend was too busy to process a request"
+      ))
+    , writeSyncCounter_(PrometheusService::counterInt(
+          "backend_operations_total_number",
+          Labels({Label{"operation", "write_sync"}}),
+          "The total number of times the backend had to write synchronously"
+      ))
+    , writeSyncRetryCounter_(PrometheusService::counterInt(
+          "backend_operations_total_number",
+          Labels({Label{"operation", "write_sync_retry"}}),
+          "The total number of times the backend had to retry a synchronous write"
+      ))
+    , asyncWriteCounters_{"write_async"}
+    , asyncReadCounters_{"read_async"}
+    , readDurationHistogram_(PrometheusService::histogramInt(
+          "backend_duration_milliseconds_histogram",
+          Labels({Label{"operation", "read"}}),
+          histogramBuckets,
+          "The duration of backend read operations including retries"
+      ))
+    , writeDurationHistogram_(PrometheusService::histogramInt(
+          "backend_duration_milliseconds_histogram",
+          Labels({Label{"operation", "write"}}),
+          histogramBuckets,
+          "The duration of backend write operations including retries"
+      ))
+{
+}
+
+BackendCounters::PtrType
+BackendCounters::make()
+{
+    struct EnableMakeShared : public BackendCounters {};
+    return std::make_shared<EnableMakeShared>();
+}
+
+void
+BackendCounters::registerTooBusy()
+{
+    ++tooBusyCounter_.get();
+}
+
+void
+BackendCounters::registerWriteSync(std::chrono::steady_clock::time_point const startTime)
+{
+    ++writeSyncCounter_.get();
+    writeDurationHistogram_.get().observe(durationInMillisecondsSince(startTime));
+}
+
+void
+BackendCounters::registerWriteSyncRetry()
+{
+    ++writeSyncRetryCounter_.get();
+}
+
+void
+BackendCounters::registerWriteStarted()
+{
+    asyncWriteCounters_.registerStarted(1u);
+}
+
+void
+BackendCounters::registerWriteFinished(std::chrono::steady_clock::time_point const startTime)
+{
+    asyncWriteCounters_.registerFinished(1u);
+    auto const duration = durationInMillisecondsSince(startTime);
+    writeDurationHistogram_.get().observe(duration);
+}
+
+void
+BackendCounters::registerWriteRetry()
+{
+    asyncWriteCounters_.registerRetry(1u);
+}
+
+void
+BackendCounters::registerReadStarted(std::uint64_t const count)
+{
+    asyncReadCounters_.registerStarted(count);
+}
+
+void
+BackendCounters::registerReadFinished(std::chrono::steady_clock::time_point const startTime, std::uint64_t const count)
+{
+    asyncReadCounters_.registerFinished(count);
+    auto const duration = durationInMillisecondsSince(startTime);
+    for (std::uint64_t i = 0; i < count; ++i)
+        readDurationHistogram_.get().observe(duration);
+}
+
+void
+BackendCounters::registerReadRetry(std::uint64_t const count)
+{
+    asyncReadCounters_.registerRetry(count);
+}
+
+void
+BackendCounters::registerReadError(std::uint64_t const count)
+{
+    asyncReadCounters_.registerError(count);
+}
+
+boost::json::object
+BackendCounters::report() const
+{
+    boost::json::object result;
+    result["too_busy"] = tooBusyCounter_.get().value();
+    result["write_sync"] = writeSyncCounter_.get().value();
+    result["write_sync_retry"] = writeSyncRetryCounter_.get().value();
+    for (auto const& [key, value] : asyncWriteCounters_.report())
+        result[key] = value;
+    for (auto const& [key, value] : asyncReadCounters_.report())
+        result[key] = value;
+    return result;
+}
+
+BackendCounters::AsyncOperationCounters::AsyncOperationCounters(std::string name)
+    : name_(std::move(name))
+    , pendingCounter_(PrometheusService::gaugeInt(
+          "backend_operations_current_number",
+          Labels({{"operation", name_}, {"status", "pending"}}),
+          "The current number of pending " + name_ + " operations"
+      ))
+    , completedCounter_(PrometheusService::counterInt(
+          "backend_operations_total_number",
+          Labels({{"operation", name_}, {"status", "completed"}}),
+          "The total number of completed " + name_ + " operations"
+      ))
+    , retryCounter_(PrometheusService::counterInt(
+          "backend_operations_total_number",
+          Labels({{"operation", name_}, {"status", "retry"}}),
+          "The total number of retried " + name_ + " operations"
+      ))
+    , errorCounter_(PrometheusService::counterInt(
+          "backend_operations_total_number",
+          Labels({{"operation", name_}, {"status", "error"}}),
+          "The total number of errored " + name_ + " operations"
+      ))
+{
+}
+
+void
+BackendCounters::AsyncOperationCounters::registerStarted(std::uint64_t const count)
+{
+    pendingCounter_.get() += count;
+}
+
+void
+BackendCounters::AsyncOperationCounters::registerFinished(std::uint64_t const count)
+{
+    ASSERT(
+        pendingCounter_.get().value() >= static_cast<std::int64_t>(count),
+        "Finished operations can't be more than pending"
+    );
+    pendingCounter_.get() -= count;
+    completedCounter_.get() += count;
+}
+
+void
+BackendCounters::AsyncOperationCounters::registerRetry(std::uint64_t count)
+{
+    retryCounter_.get() += count;
+}
+
+void
+BackendCounters::AsyncOperationCounters::registerError(std::uint64_t count)
+{
+    ASSERT(
+        pendingCounter_.get().value() >= static_cast<std::int64_t>(count), "Error operations can't be more than pending"
+    );
+    pendingCounter_.get() -= count;
+    errorCounter_.get() += count;
+}
+
+boost::json::object
+BackendCounters::AsyncOperationCounters::report() const
+{
+    return boost::json::object{
+        {name_ + "_pending", pendingCounter_.get().value()},
+        {name_ + "_completed", completedCounter_.get().value()},
+        {name_ + "_retry", retryCounter_.get().value()},
+        {name_ + "_error", errorCounter_.get().value()}
+    };
+}
+
+}  // namespace data

src/data/BackendCounters.hpp

@@ -0,0 +1,164 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of clio: https://github.com/XRPLF/clio
+    Copyright (c) 2023, the clio developers.
+
+    Permission to use, copy, modify, and distribute this software for any
+    purpose with or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL,  DIRECT,  INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+
+#pragma once
+
+#include "util/prometheus/Counter.hpp"
+#include "util/prometheus/Gauge.hpp"
+#include "util/prometheus/Histogram.hpp"
+
+#include <boost/json/object.hpp>
+
+#include <chrono>
+#include <cstdint>
+#include <functional>
+#include <memory>
+#include <string>
+
+namespace data {
+
+/**
+ * @brief A concept for a class that can be used to count backend operations.
+ */
+template <typename T>
+concept SomeBackendCounters = requires(T a) {
+    typename T::PtrType;
+    {
+        a.registerTooBusy()
+    } -> std::same_as<void>;
+    {
+        a.registerWriteSync(std::chrono::steady_clock::time_point{})
+    } -> std::same_as<void>;
+    {
+        a.registerWriteSyncRetry()
+    } -> std::same_as<void>;
+    {
+        a.registerWriteStarted()
+    } -> std::same_as<void>;
+    {
+        a.registerWriteFinished(std::chrono::steady_clock::time_point{})
+    } -> std::same_as<void>;
+    {
+        a.registerWriteRetry()
+    } -> std::same_as<void>;
+    {
+        a.registerReadStarted(std::uint64_t{})
+    } -> std::same_as<void>;
+    {
+        a.registerReadFinished(std::chrono::steady_clock::time_point{}, std::uint64_t{})
+    } -> std::same_as<void>;
+    {
+        a.registerReadRetry(std::uint64_t{})
+    } -> std::same_as<void>;
+    {
+        a.registerReadError(std::uint64_t{})
+    } -> std::same_as<void>;
+    {
+        a.report()
+    } -> std::same_as<boost::json::object>;
+};
+
+/**
+ * @brief Holds statistics about the backend.
+ *
+ * @note This class is thread-safe.
+ */
+class BackendCounters {
+public:
+    using PtrType = std::shared_ptr<BackendCounters>;
+
+    static PtrType
+    make();
+
+    void
+    registerTooBusy();
+
+    void
+    registerWriteSync(std::chrono::steady_clock::time_point startTime);
+
+    void
+    registerWriteSyncRetry();
+
+    void
+    registerWriteStarted();
+
+    void
+    registerWriteFinished(std::chrono::steady_clock::time_point startTime);
+
+    void
+    registerWriteRetry();
+
+    void
+    registerReadStarted(std::uint64_t count = 1u);
+
+    void
+    registerReadFinished(std::chrono::steady_clock::time_point startTime, std::uint64_t count = 1u);
+
+    void
+    registerReadRetry(std::uint64_t count = 1u);
+
+    void
+    registerReadError(std::uint64_t count = 1u);
+
+    boost::json::object
+    report() const;
+
+private:
+    BackendCounters();
+
+    class AsyncOperationCounters {
+    public:
+        AsyncOperationCounters(std::string name);
+
+        void
+        registerStarted(std::uint64_t count);
+
+        void
+        registerFinished(std::uint64_t count);
+
+        void
+        registerRetry(std::uint64_t count);
+
+        void
+        registerError(std::uint64_t count);
+
+        boost::json::object
+        report() const;
+
+    private:
+        std::string name_;
+        std::reference_wrapper<util::prometheus::GaugeInt> pendingCounter_;
+        std::reference_wrapper<util::prometheus::CounterInt> completedCounter_;
+        std::reference_wrapper<util::prometheus::CounterInt> retryCounter_;
+        std::reference_wrapper<util::prometheus::CounterInt> errorCounter_;
+    };
+
+    std::reference_wrapper<util::prometheus::CounterInt> tooBusyCounter_;
+
+    std::reference_wrapper<util::prometheus::CounterInt> writeSyncCounter_;
+    std::reference_wrapper<util::prometheus::CounterInt> writeSyncRetryCounter_;
+
+    AsyncOperationCounters asyncWriteCounters_{"write_async"};
+    AsyncOperationCounters asyncReadCounters_{"read_async"};
+
+    std::reference_wrapper<util::prometheus::HistogramInt> readDurationHistogram_;
+    std::reference_wrapper<util::prometheus::HistogramInt> writeDurationHistogram_;
+};
+
+}  // namespace data

src/data/BackendFactory.hpp

@@ -19,52 +19,52 @@
 
 #pragma once
 
-#include <backend/BackendInterface.h>
-#include <backend/CassandraBackend.h>
-#include <backend/CassandraBackendNew.h>
-#include <config/Config.h>
-#include <log/Logger.h>
+#include "data/BackendInterface.hpp"
+#include "data/CassandraBackend.hpp"
+#include "data/cassandra/SettingsProvider.hpp"
+#include "util/config/Config.hpp"
+#include "util/log/Logger.hpp"
 
 #include <boost/algorithm/string.hpp>
+#include <boost/algorithm/string/predicate.hpp>
 
-namespace Backend {
-std::shared_ptr<BackendInterface>
-make_Backend(boost::asio::io_context& ioc, clio::Config const& config)
+#include <memory>
+#include <stdexcept>
+#include <string>
+
+namespace data {
+
+/**
+ * @brief A factory function that creates the backend based on a config.
+ *
+ * @param config The clio config to use
+ * @return A shared_ptr<BackendInterface> with the selected implementation
+ */
+inline std::shared_ptr<BackendInterface>
+make_Backend(util::Config const& config)
 {
-    static clio::Logger log{"Backend"};
-    log.info() << "Constructing BackendInterface";
+    static util::Logger const log{"Backend"};
+    LOG(log.info()) << "Constructing BackendInterface";
 
-    auto readOnly = config.valueOr("read_only", false);
-    auto type = config.value<std::string>("database.type");
+    auto const readOnly = config.valueOr("read_only", false);
+
+    auto const type = config.value<std::string>("database.type");
     std::shared_ptr<BackendInterface> backend = nullptr;
 
-    if (boost::iequals(type, "cassandra"))
-    {
+    // TODO: retire `cassandra-new` by next release after 2.0
+    if (boost::iequals(type, "cassandra") or boost::iequals(type, "cassandra-new")) {
         auto cfg = config.section("database." + type);
-        auto ttl = config.valueOr<uint32_t>("online_delete", 0) * 4;
-        backend = std::make_shared<CassandraBackend>(ioc, cfg, ttl);
-    }
-    else if (boost::iequals(type, "cassandra-new"))
-    {
-        auto cfg = config.section("database." + type);
-        auto ttl = config.valueOr<uint16_t>("online_delete", 0) * 4;
-        backend =
-            std::make_shared<Backend::Cassandra::CassandraBackend>(Backend::Cassandra::SettingsProvider{cfg, ttl});
+        backend = std::make_shared<data::cassandra::CassandraBackend>(data::cassandra::SettingsProvider{cfg}, readOnly);
     }
 
     if (!backend)
         throw std::runtime_error("Invalid database type");
 
-    backend->open(readOnly);
-    auto rng = backend->hardFetchLedgerRangeNoThrow();
+    auto const rng = backend->hardFetchLedgerRangeNoThrow();
     if (rng)
-    {
-        backend->updateRange(rng->minSequence);
-        backend->updateRange(rng->maxSequence);
-    }
-
-    log.info() << "Constructed BackendInterface Successfully";
+        backend->setRange(rng->minSequence, rng->maxSequence);
 
+    LOG(log.info()) << "Constructed BackendInterface Successfully";
     return backend;
 }
-}  // namespace Backend
+}  // namespace data

src/data/BackendInterface.cpp

@@ -0,0 +1,387 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of clio: https://github.com/XRPLF/clio
+    Copyright (c) 2022, the clio developers.
+
+    Permission to use, copy, modify, and distribute this software for any
+    purpose with or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL,  DIRECT,  INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+
+#include "data/BackendInterface.hpp"
+
+#include "data/Types.hpp"
+#include "util/Assert.hpp"
+#include "util/log/Logger.hpp"
+
+#include <boost/asio/spawn.hpp>
+#include <ripple/basics/base_uint.h>
+#include <ripple/basics/strHex.h>
+#include <ripple/protocol/Fees.h>
+#include <ripple/protocol/Indexes.h>
+#include <ripple/protocol/SField.h>
+#include <ripple/protocol/STLedgerEntry.h>
+#include <ripple/protocol/Serializer.h>
+
+#include <chrono>
+#include <cstddef>
+#include <cstdint>
+#include <mutex>
+#include <optional>
+#include <shared_mutex>
+#include <sstream>
+#include <string>
+#include <utility>
+#include <vector>
+
+// local to compilation unit loggers
+namespace {
+util::Logger gLog{"Backend"};
+}  // namespace
+
+namespace data {
+bool
+BackendInterface::finishWrites(std::uint32_t const ledgerSequence)
+{
+    LOG(gLog.debug()) << "Want finish writes for " << ledgerSequence;
+    auto commitRes = doFinishWrites();
+    if (commitRes) {
+        LOG(gLog.debug()) << "Successfully commited. Updating range now to " << ledgerSequence;
+        updateRange(ledgerSequence);
+    }
+    return commitRes;
+}
+void
+BackendInterface::writeLedgerObject(std::string&& key, std::uint32_t const seq, std::string&& blob)
+{
+    ASSERT(key.size() == sizeof(ripple::uint256), "Key must be 256 bits");
+    doWriteLedgerObject(std::move(key), seq, std::move(blob));
+}
+
+std::optional<LedgerRange>
+BackendInterface::hardFetchLedgerRangeNoThrow() const
+{
+    return retryOnTimeout([&]() { return hardFetchLedgerRange(); });
+}
+
+// *** state data methods
+std::optional<Blob>
+BackendInterface::fetchLedgerObject(
+    ripple::uint256 const& key,
+    std::uint32_t const sequence,
+    boost::asio::yield_context yield
+) const
+{
+    auto obj = cache_.get(key, sequence);
+    if (obj) {
+        LOG(gLog.trace()) << "Cache hit - " << ripple::strHex(key);
+        return *obj;
+    }
+
+    LOG(gLog.trace()) << "Cache miss - " << ripple::strHex(key);
+    auto dbObj = doFetchLedgerObject(key, sequence, yield);
+    if (!dbObj) {
+        LOG(gLog.trace()) << "Missed cache and missed in db";
+    } else {
+        LOG(gLog.trace()) << "Missed cache but found in db";
+    }
+    return dbObj;
+}
+
+std::vector<Blob>
+BackendInterface::fetchLedgerObjects(
+    std::vector<ripple::uint256> const& keys,
+    std::uint32_t const sequence,
+    boost::asio::yield_context yield
+) const
+{
+    std::vector<Blob> results;
+    results.resize(keys.size());
+    std::vector<ripple::uint256> misses;
+    for (size_t i = 0; i < keys.size(); ++i) {
+        auto obj = cache_.get(keys[i], sequence);
+        if (obj) {
+            results[i] = *obj;
+        } else {
+            misses.push_back(keys[i]);
+        }
+    }
+    LOG(gLog.trace()) << "Cache hits = " << keys.size() - misses.size() << " - cache misses = " << misses.size();
+
+    if (!misses.empty()) {
+        auto objs = doFetchLedgerObjects(misses, sequence, yield);
+        for (size_t i = 0, j = 0; i < results.size(); ++i) {
+            if (results[i].empty()) {
+                results[i] = objs[j];
+                ++j;
+            }
+        }
+    }
+
+    return results;
+}
+
+// Fetches the successor to key/index
+std::optional<ripple::uint256>
+BackendInterface::fetchSuccessorKey(
+    ripple::uint256 key,
+    std::uint32_t const ledgerSequence,
+    boost::asio::yield_context yield
+) const
+{
+    auto succ = cache_.getSuccessor(key, ledgerSequence);
+    if (succ) {
+        LOG(gLog.trace()) << "Cache hit - " << ripple::strHex(key);
+    } else {
+        LOG(gLog.trace()) << "Cache miss - " << ripple::strHex(key);
+    }
+    return succ ? succ->key : doFetchSuccessorKey(key, ledgerSequence, yield);
+}
+
+std::optional<LedgerObject>
+BackendInterface::fetchSuccessorObject(
+    ripple::uint256 key,
+    std::uint32_t const ledgerSequence,
+    boost::asio::yield_context yield
+) const
+{
+    auto succ = fetchSuccessorKey(key, ledgerSequence, yield);
+    if (succ) {
+        auto obj = fetchLedgerObject(*succ, ledgerSequence, yield);
+        if (!obj)
+            return {{*succ, {}}};
+
+        return {{*succ, *obj}};
+    }
+    return {};
+}
+
+BookOffersPage
+BackendInterface::fetchBookOffers(
+    ripple::uint256 const& book,
+    std::uint32_t const ledgerSequence,
+    std::uint32_t const limit,
+    boost::asio::yield_context yield
+) const
+{
+    // TODO try to speed this up. This can take a few seconds. The goal is
+    // to get it down to a few hundred milliseconds.
+    BookOffersPage page;
+    ripple::uint256 const bookEnd = ripple::getQualityNext(book);
+    ripple::uint256 uTipIndex = book;
+    std::vector<ripple::uint256> keys;
+    auto getMillis = [](auto diff) { return std::chrono::duration_cast<std::chrono::milliseconds>(diff).count(); };
+    auto begin = std::chrono::system_clock::now();
+    std::uint32_t numSucc = 0;
+    std::uint32_t numPages = 0;
+    long succMillis = 0;
+    long pageMillis = 0;
+    while (keys.size() < limit) {
+        auto mid1 = std::chrono::system_clock::now();
+        auto offerDir = fetchSuccessorObject(uTipIndex, ledgerSequence, yield);
+        auto mid2 = std::chrono::system_clock::now();
+        numSucc++;
+        succMillis += getMillis(mid2 - mid1);
+        if (!offerDir || offerDir->key >= bookEnd) {
+            LOG(gLog.trace()) << "offerDir.has_value() " << offerDir.has_value() << " breaking";
+            break;
+        }
+        uTipIndex = offerDir->key;
+        while (keys.size() < limit) {
+            ++numPages;
+            ripple::STLedgerEntry const sle{
+                ripple::SerialIter{offerDir->blob.data(), offerDir->blob.size()}, offerDir->key
+            };
+            auto indexes = sle.getFieldV256(ripple::sfIndexes);
+            keys.insert(keys.end(), indexes.begin(), indexes.end());
+            auto next = sle.getFieldU64(ripple::sfIndexNext);
+            if (next == 0u) {
+                LOG(gLog.trace()) << "Next is empty. breaking";
+                break;
+            }
+            auto nextKey = ripple::keylet::page(uTipIndex, next);
+            auto nextDir = fetchLedgerObject(nextKey.key, ledgerSequence, yield);
+            ASSERT(nextDir.has_value(), "Next dir must exist");
+            offerDir->blob = *nextDir;
+            offerDir->key = nextKey.key;
+        }
+        auto mid3 = std::chrono::system_clock::now();
+        pageMillis += getMillis(mid3 - mid2);
+    }
+    auto mid = std::chrono::system_clock::now();
+    auto objs = fetchLedgerObjects(keys, ledgerSequence, yield);
+    for (size_t i = 0; i < keys.size() && i < limit; ++i) {
+        LOG(gLog.trace()) << "Key = " << ripple::strHex(keys[i]) << " blob = " << ripple::strHex(objs[i])
+                          << " ledgerSequence = " << ledgerSequence;
+        ASSERT(!objs[i].empty(), "Ledger object can't be empty");
+        page.offers.push_back({keys[i], objs[i]});
+    }
+    auto end = std::chrono::system_clock::now();
+    LOG(gLog.debug()) << "Fetching " << std::to_string(keys.size()) << " offers took "
+                      << std::to_string(getMillis(mid - begin)) << " milliseconds. Fetching next dir took "
+                      << std::to_string(succMillis) << " milliseonds. Fetched next dir " << std::to_string(numSucc)
+                      << " times"
+                      << " Fetching next page of dir took " << std::to_string(pageMillis) << " milliseconds"
+                      << ". num pages = " << std::to_string(numPages) << ". Fetching all objects took "
+                      << std::to_string(getMillis(end - mid))
+                      << " milliseconds. total time = " << std::to_string(getMillis(end - begin)) << " milliseconds"
+                      << " book = " << ripple::strHex(book);
+
+    return page;
+}
+
+std::optional<LedgerRange>
+BackendInterface::hardFetchLedgerRange() const
+{
+    return synchronous([this](auto yield) { return hardFetchLedgerRange(yield); });
+}
+
+std::optional<LedgerRange>
+BackendInterface::fetchLedgerRange() const
+{
+    std::shared_lock const lck(rngMtx_);
+    return range;
+}
+
+void
+BackendInterface::updateRange(uint32_t newMax)
+{
+    std::scoped_lock const lck(rngMtx_);
+
+    ASSERT(
+        !range || newMax >= range->maxSequence,
+        "Range shouldn't exist yet or newMax should be greater. newMax = {}, range->maxSequence = {}",
+        newMax,
+        range->maxSequence
+    );
+
+    if (!range) {
+        range = {newMax, newMax};
+    } else {
+        range->maxSequence = newMax;
+    }
+}
+
+void
+BackendInterface::setRange(uint32_t min, uint32_t max, bool force)
+{
+    std::scoped_lock const lck(rngMtx_);
+
+    if (!force) {
+        ASSERT(min <= max, "Range min must be less than or equal to max");
+        ASSERT(not range.has_value(), "Range was already set");
+    }
+
+    range = {min, max};
+}
+
+LedgerPage
+BackendInterface::fetchLedgerPage(
+    std::optional<ripple::uint256> const& cursor,
+    std::uint32_t const ledgerSequence,
+    std::uint32_t const limit,
+    bool outOfOrder,
+    boost::asio::yield_context yield
+) const
+{
+    LedgerPage page;
+
+    std::vector<ripple::uint256> keys;
+    bool reachedEnd = false;
+    while (keys.size() < limit && !reachedEnd) {
+        ripple::uint256 const& curCursor = !keys.empty() ? keys.back() : (cursor ? *cursor : firstKey);
+        std::uint32_t const seq = outOfOrder ? range->maxSequence : ledgerSequence;
+        auto succ = fetchSuccessorKey(curCursor, seq, yield);
+        if (!succ) {
+            reachedEnd = true;
+        } else {
+            keys.push_back(*succ);
+        }
+    }
+
+    auto objects = fetchLedgerObjects(keys, ledgerSequence, yield);
+    for (size_t i = 0; i < objects.size(); ++i) {
+        if (!objects[i].empty()) {
+            page.objects.push_back({keys[i], std::move(objects[i])});
+        } else if (!outOfOrder) {
+            LOG(gLog.error()) << "Deleted or non-existent object in successor table. key = " << ripple::strHex(keys[i])
+                              << " - seq = " << ledgerSequence;
+            std::stringstream msg;
+            for (size_t j = 0; j < objects.size(); ++j) {
+                msg << " - " << ripple::strHex(keys[j]);
+            }
+            LOG(gLog.error()) << msg.str();
+        }
+    }
+    if (!keys.empty() && !reachedEnd)
+        page.cursor = keys.back();
+
+    return page;
+}
+
+std::optional<ripple::Fees>
+BackendInterface::fetchFees(std::uint32_t const seq, boost::asio::yield_context yield) const
+{
+    ripple::Fees fees;
+
+    auto key = ripple::keylet::fees().key;
+    auto bytes = fetchLedgerObject(key, seq, yield);
+
+    if (!bytes) {
+        LOG(gLog.error()) << "Could not find fees";
+        return {};
+    }
+
+    ripple::SerialIter it(bytes->data(), bytes->size());
+    ripple::SLE const sle{it, key};
+
+    // XRPFees amendment introduced new fields for fees calculations.
+    // New fields are set and the old fields are removed via `set_fees` tx.
+    // Fallback to old fields if `set_fees` was not yet used to update the fields on this tx.
+    auto hasNewFields = false;
+    {
+        auto const baseFeeXRP = sle.at(~ripple::sfBaseFeeDrops);
+        auto const reserveBaseXRP = sle.at(~ripple::sfReserveBaseDrops);
+        auto const reserveIncrementXRP = sle.at(~ripple::sfReserveIncrementDrops);
+
+        if (baseFeeXRP)
+            fees.base = baseFeeXRP->xrp();
+
+        if (reserveBaseXRP)
+            fees.reserve = reserveBaseXRP->xrp();
+
+        if (reserveIncrementXRP)
+            fees.increment = reserveIncrementXRP->xrp();
+
+        hasNewFields = baseFeeXRP || reserveBaseXRP || reserveIncrementXRP;
+    }
+
+    if (not hasNewFields) {
+        // Fallback to old fields
+        auto const baseFee = sle.at(~ripple::sfBaseFee);
+        auto const reserveBase = sle.at(~ripple::sfReserveBase);
+        auto const reserveIncrement = sle.at(~ripple::sfReserveIncrement);
+
+        if (baseFee)
+            fees.base = baseFee.value();
+
+        if (reserveBase)
+            fees.reserve = reserveBase.value();
+
+        if (reserveIncrement)
+            fees.increment = reserveIncrement.value();
+    }
+
+    return fees;
+}
+
+}  // namespace data

src/data/BackendInterface.hpp

@@ -0,0 +1,615 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of clio: https://github.com/XRPLF/clio
+    Copyright (c) 2022, the clio developers.
+
+    Permission to use, copy, modify, and distribute this software for any
+    purpose with or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL,  DIRECT,  INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+
+#pragma once
+
+#include "data/DBHelpers.hpp"
+#include "data/LedgerCache.hpp"
+#include "data/Types.hpp"
+#include "util/log/Logger.hpp"
+
+#include <boost/asio/executor_work_guard.hpp>
+#include <boost/asio/io_context.hpp>
+#include <boost/asio/spawn.hpp>
+#include <boost/json.hpp>
+#include <boost/json/object.hpp>
+#include <boost/utility/result_of.hpp>
+#include <ripple/basics/base_uint.h>
+#include <ripple/protocol/AccountID.h>
+#include <ripple/protocol/Fees.h>
+#include <ripple/protocol/LedgerHeader.h>
+
+#include <chrono>
+#include <cstddef>
+#include <cstdint>
+#include <exception>
+#include <optional>
+#include <shared_mutex>
+#include <string>
+#include <thread>
+#include <type_traits>
+#include <vector>
+
+namespace data {
+
+/**
+ * @brief Represents a database timeout error.
+ */
+class DatabaseTimeout : public std::exception {
+public:
+    char const*
+    what() const throw() override
+    {
+        return "Database read timed out. Please retry the request";
+    }
+};
+
+static constexpr std::size_t DEFAULT_WAIT_BETWEEN_RETRY = 500;
+/**
+ * @brief A helper function that catches DatabaseTimout exceptions and retries indefinitely.
+ *
+ * @tparam FnType The type of function object to execute
+ * @param func The function object to execute
+ * @param waitMs Delay between retry attempts
+ * @return auto The same as the return type of func
+ */
+template <class FnType>
+auto
+retryOnTimeout(FnType func, size_t waitMs = DEFAULT_WAIT_BETWEEN_RETRY)
+{
+    static util::Logger const log{"Backend"};
+
+    while (true) {
+        try {
+            return func();
+        } catch (DatabaseTimeout const&) {
+            LOG(log.error()) << "Database request timed out. Sleeping and retrying ... ";
+            std::this_thread::sleep_for(std::chrono::milliseconds(waitMs));
+        }
+    }
+}
+
+/**
+ * @brief Synchronously executes the given function object inside a coroutine.
+ *
+ * @tparam FnType The type of function object to execute
+ * @param func The function object to execute
+ * @return auto The same as the return type of func
+ */
+template <class FnType>
+auto
+synchronous(FnType&& func)
+{
+    boost::asio::io_context ctx;
+
+    using R = typename boost::result_of<FnType(boost::asio::yield_context)>::type;
+    if constexpr (!std::is_same_v<R, void>) {
+        R res;
+        boost::asio::spawn(ctx, [_ = boost::asio::make_work_guard(ctx), &func, &res](auto yield) {
+            res = func(yield);
+        });
+
+        ctx.run();
+        return res;
+    } else {
+        boost::asio::spawn(ctx, [_ = boost::asio::make_work_guard(ctx), &func](auto yield) { func(yield); });
+        ctx.run();
+    }
+}
+
+/**
+ * @brief Synchronously execute the given function object and retry until no DatabaseTimeout is thrown.
+ *
+ * @tparam FnType The type of function object to execute
+ * @param func The function object to execute
+ * @return auto The same as the return type of func
+ */
+template <class FnType>
+auto
+synchronousAndRetryOnTimeout(FnType&& func)
+{
+    return retryOnTimeout([&]() { return synchronous(func); });
+}
+
+/**
+ * @brief The interface to the database used by Clio.
+ */
+class BackendInterface {
+protected:
+    mutable std::shared_mutex rngMtx_;
+    std::optional<LedgerRange> range;
+    LedgerCache cache_;
+
+public:
+    BackendInterface() = default;
+    virtual ~BackendInterface() = default;
+
+    // TODO: Remove this hack. Cache should not be exposed thru BackendInterface
+    /**
+     * @return Immutable cache
+     */
+    LedgerCache const&
+    cache() const
+    {
+        return cache_;
+    }
+
+    /**
+     * @return Mutable cache
+     */
+    LedgerCache&
+    cache()
+    {
+        return cache_;
+    }
+
+    /**
+     * @brief Fetches a specific ledger by sequence number.
+     *
+     * @param sequence The sequence number to fetch for
+     * @param yield The coroutine context
+     * @return The ripple::LedgerHeader if found; nullopt otherwise
+     */
+    virtual std::optional<ripple::LedgerHeader>
+    fetchLedgerBySequence(std::uint32_t sequence, boost::asio::yield_context yield) const = 0;
+
+    /**
+     * @brief Fetches a specific ledger by hash.
+     *
+     * @param hash The hash to fetch for
+     * @param yield The coroutine context
+     * @return The ripple::LedgerHeader if found; nullopt otherwise
+     */
+    virtual std::optional<ripple::LedgerHeader>
+    fetchLedgerByHash(ripple::uint256 const& hash, boost::asio::yield_context yield) const = 0;
+
+    /**
+     * @brief Fetches the latest ledger sequence.
+     *
+     * @param yield The coroutine context
+     * @return Latest sequence wrapped in an optional if found; nullopt otherwise
+     */
+    virtual std::optional<std::uint32_t>
+    fetchLatestLedgerSequence(boost::asio::yield_context yield) const = 0;
+
+    /**
+     * @brief Fetch the current ledger range.
+     *
+     * @return The current ledger range if populated; nullopt otherwise
+     */
+    std::optional<LedgerRange>
+    fetchLedgerRange() const;
+
+    /**
+     * @brief Updates the range of sequences that are stored in the DB.
+     *
+     * @param newMax The new maximum sequence available
+     */
+    void
+    updateRange(uint32_t newMax);
+
+    /**
+     * @brief Sets the range of sequences that are stored in the DB.
+     *
+     * @param min The new minimum sequence available
+     * @param max The new maximum sequence available
+     * @param force If set to true, the range will be set even if it's already set
+     */
+    void
+    setRange(uint32_t min, uint32_t max, bool force = false);
+
+    /**
+     * @brief Fetch the fees from a specific ledger sequence.
+     *
+     * @param seq The sequence to fetch for
+     * @param yield The coroutine context
+     * @return ripple::Fees if fees are found; nullopt otherwise
+     */
+    std::optional<ripple::Fees>
+    fetchFees(std::uint32_t seq, boost::asio::yield_context yield) const;
+
+    /**
+     * @brief Fetches a specific transaction.
+     *
+     * @param hash The hash of the transaction to fetch
+     * @param yield The coroutine context
+     * @return TransactionAndMetadata if transaction is found; nullopt otherwise
+     */
+    virtual std::optional<TransactionAndMetadata>
+    fetchTransaction(ripple::uint256 const& hash, boost::asio::yield_context yield) const = 0;
+
+    /**
+     * @brief Fetches multiple transactions.
+     *
+     * @param hashes A vector of hashes to fetch transactions for
+     * @param yield The coroutine context
+     * @return A vector of TransactionAndMetadata matching the given hashes
+     */
+    virtual std::vector<TransactionAndMetadata>
+    fetchTransactions(std::vector<ripple::uint256> const& hashes, boost::asio::yield_context yield) const = 0;
+
+    /**
+     * @brief Fetches all transactions for a specific account.
+     *
+     * @param account The account to fetch transactions for
+     * @param limit The maximum number of transactions per result page
+     * @param forward Whether to fetch the page forwards or backwards from the given cursor
+     * @param cursor The cursor to resume fetching from
+     * @param yield The coroutine context
+     * @return Results and a cursor to resume from
+     */
+    virtual TransactionsAndCursor
+    fetchAccountTransactions(
+        ripple::AccountID const& account,
+        std::uint32_t limit,
+        bool forward,
+        std::optional<TransactionsCursor> const& cursor,
+        boost::asio::yield_context yield
+    ) const = 0;
+
+    /**
+     * @brief Fetches all transactions from a specific ledger.
+     *
+     * @param ledgerSequence The ledger sequence to fetch for
+     * @param yield The coroutine context
+     * @return Results as a vector of TransactionAndMetadata
+     */
+    virtual std::vector<TransactionAndMetadata>
+    fetchAllTransactionsInLedger(std::uint32_t ledgerSequence, boost::asio::yield_context yield) const = 0;
+
+    /**
+     * @brief Fetches all transaction hashes from a specific ledger.
+     *
+     * @param ledgerSequence The ledger sequence to fetch for
+     * @param yield The coroutine context
+     * @return Hashes as ripple::uint256 in a vector
+     */
+    virtual std::vector<ripple::uint256>
+    fetchAllTransactionHashesInLedger(std::uint32_t ledgerSequence, boost::asio::yield_context yield) const = 0;
+
+    /**
+     * @brief Fetches a specific NFT.
+     *
+     * @param tokenID The ID of the NFT
+     * @param ledgerSequence The ledger sequence to fetch for
+     * @param yield The coroutine context
+     * @return NFT object on success; nullopt otherwise
+     */
+    virtual std::optional<NFT>
+    fetchNFT(ripple::uint256 const& tokenID, std::uint32_t ledgerSequence, boost::asio::yield_context yield) const = 0;
+
+    /**
+     * @brief Fetches all transactions for a specific NFT.
+     *
+     * @param tokenID The ID of the NFT
+     * @param limit The maximum number of transactions per result page
+     * @param forward Whether to fetch the page forwards or backwards from the given cursor
+     * @param cursorIn The cursor to resume fetching from
+     * @param yield The coroutine context
+     * @return Results and a cursor to resume from
+     */
+    virtual TransactionsAndCursor
+    fetchNFTTransactions(
+        ripple::uint256 const& tokenID,
+        std::uint32_t limit,
+        bool forward,
+        std::optional<TransactionsCursor> const& cursorIn,
+        boost::asio::yield_context yield
+    ) const = 0;
+
+    /**
+     * @brief Fetches all NFTs issued by a given address.
+     *
+     * @param issuer AccountID of issuer you wish you query.
+     * @param taxon Optional taxon of NFTs by which you wish to filter.
+     * @param limit Paging limit.
+     * @param cursorIn Optional cursor to allow us to pick up from where we
+     * last left off.
+     * @param yield Currently executing coroutine.
+     * @return std::vector<NFT> of NFTs issued by this account, or
+     * this issuer/taxon combination if taxon is passed and an optional marker
+     */
+    virtual NFTsAndCursor
+    fetchNFTsByIssuer(
+        ripple::AccountID const& issuer,
+        std::optional<std::uint32_t> const& taxon,
+        std::uint32_t ledgerSequence,
+        std::uint32_t limit,
+        std::optional<ripple::uint256> const& cursorIn,
+        boost::asio::yield_context yield
+    ) const = 0;
+
+    /**
+     * @brief Fetches a specific ledger object.
+     *
+     * Currently the real fetch happens in doFetchLedgerObject and fetchLedgerObject attempts to fetch from Cache first
+     * and only calls out to the real DB if a cache miss ocurred.
+     *
+     * @param key The key of the object
+     * @param sequence The ledger sequence to fetch for
+     * @param yield The coroutine context
+     * @return The object as a Blob on success; nullopt otherwise
+     */
+    std::optional<Blob>
+    fetchLedgerObject(ripple::uint256 const& key, std::uint32_t sequence, boost::asio::yield_context yield) const;
+
+    /**
+     * @brief Fetches all ledger objects by their keys.
+     *
+     * Currently the real fetch happens in doFetchLedgerObjects and fetchLedgerObjects attempts to fetch from Cache
+     * first and only calls out to the real DB for each of the keys that was not found in the cache.
+     *
+     * @param keys A vector with the keys of the objects to fetch
+     * @param sequence The ledger sequence to fetch for
+     * @param yield The coroutine context
+     * @return A vector of ledger objects as Blobs
+     */
+    std::vector<Blob>
+    fetchLedgerObjects(
+        std::vector<ripple::uint256> const& keys,
+        std::uint32_t sequence,
+        boost::asio::yield_context yield
+    ) const;
+
+    /**
+     * @brief The database-specific implementation for fetching a ledger object.
+     *
+     * @param key The key to fetch for
+     * @param sequence The ledger sequence to fetch for
+     * @param yield The coroutine context
+     * @return The object as a Blob on success; nullopt otherwise
+     */
+    virtual std::optional<Blob>
+    doFetchLedgerObject(ripple::uint256 const& key, std::uint32_t sequence, boost::asio::yield_context yield) const = 0;
+
+    /**
+     * @brief The database-specific implementation for fetching ledger objects.
+     *
+     * @param keys The keys to fetch for
+     * @param sequence The ledger sequence to fetch for
+     * @param yield The coroutine context
+     * @return A vector of Blobs representing each fetched object
+     */
+    virtual std::vector<Blob>
+    doFetchLedgerObjects(
+        std::vector<ripple::uint256> const& keys,
+        std::uint32_t sequence,
+        boost::asio::yield_context yield
+    ) const = 0;
+
+    /**
+     * @brief Returns the difference between ledgers.
+     *
+     * @param ledgerSequence The ledger sequence to fetch for
+     * @param yield The coroutine context
+     * @return A vector of LedgerObject representing the diff
+     */
+    virtual std::vector<LedgerObject>
+    fetchLedgerDiff(std::uint32_t ledgerSequence, boost::asio::yield_context yield) const = 0;
+
+    /**
+     * @brief Fetches a page of ledger objects, ordered by key/index.
+     *
+     * @param cursor The cursor to resume fetching from
+     * @param ledgerSequence The ledger sequence to fetch for
+     * @param limit The maximum number of transactions per result page
+     * @param outOfOrder If set to true max available sequence is used instead of ledgerSequence
+     * @param yield The coroutine context
+     * @return The ledger page
+     */
+    LedgerPage
+    fetchLedgerPage(
+        std::optional<ripple::uint256> const& cursor,
+        std::uint32_t ledgerSequence,
+        std::uint32_t limit,
+        bool outOfOrder,
+        boost::asio::yield_context yield
+    ) const;
+
+    /**
+     * @brief Fetches the successor object.
+     *
+     * @param key The key to fetch for
+     * @param ledgerSequence The ledger sequence to fetch for
+     * @param yield The coroutine context
+     * @return The sucessor on success; nullopt otherwise
+     */
+    std::optional<LedgerObject>
+    fetchSuccessorObject(ripple::uint256 key, std::uint32_t ledgerSequence, boost::asio::yield_context yield) const;
+
+    /**
+     * @brief Fetches the successor key.
+     *
+     * Thea real fetch happens in doFetchSuccessorKey. This function will attempt to lookup the successor in the cache
+     * first and only if it's not found in the cache will it fetch from the actual DB.
+     *
+     * @param key The key to fetch for
+     * @param ledgerSequence The ledger sequence to fetch for
+     * @param yield The coroutine context
+     * @return The sucessor key on success; nullopt otherwise
+     */
+    std::optional<ripple::uint256>
+    fetchSuccessorKey(ripple::uint256 key, std::uint32_t ledgerSequence, boost::asio::yield_context yield) const;
+
+    /**
+     * @brief Database-specific implementation of fetching the successor key
+     *
+     * @param key The key to fetch for
+     * @param ledgerSequence The ledger sequence to fetch for
+     * @param yield The coroutine context
+     * @return The sucessor on success; nullopt otherwise
+     */
+    virtual std::optional<ripple::uint256>
+    doFetchSuccessorKey(ripple::uint256 key, std::uint32_t ledgerSequence, boost::asio::yield_context yield) const = 0;
+
+    /**
+     * @brief Fetches book offers.
+     *
+     * @param book Unsigned 256-bit integer.
+     * @param ledgerSequence The ledger sequence to fetch for
+     * @param limit Pagaing limit as to how many transactions returned per page.
+     * @param yield The coroutine context
+     * @return The book offers page
+     */
+    BookOffersPage
+    fetchBookOffers(
+        ripple::uint256 const& book,
+        std::uint32_t ledgerSequence,
+        std::uint32_t limit,
+        boost::asio::yield_context yield
+    ) const;
+
+    /**
+     * @brief Synchronously fetches the ledger range from DB.
+     *
+     * This function just wraps hardFetchLedgerRange(boost::asio::yield_context) using synchronous(FnType&&).
+     *
+     * @return The ledger range if available; nullopt otherwise
+     */
+    std::optional<LedgerRange>
+    hardFetchLedgerRange() const;
+
+    /**
+     * @brief Fetches the ledger range from DB.
+     *
+     * @return The ledger range if available; nullopt otherwise
+     */
+    virtual std::optional<LedgerRange>
+    hardFetchLedgerRange(boost::asio::yield_context yield) const = 0;
+
+    /**
+     * @brief Fetches the ledger range from DB retrying until no DatabaseTimeout is thrown.
+     *
+     * @return The ledger range if available; nullopt otherwise
+     */
+    std::optional<LedgerRange>
+    hardFetchLedgerRangeNoThrow() const;
+
+    /**
+     * @brief Writes to a specific ledger.
+     *
+     * @param ledgerHeader Ledger header.
+     * @param blob r-value string serialization of ledger header.
+     */
+    virtual void
+    writeLedger(ripple::LedgerHeader const& ledgerHeader, std::string&& blob) = 0;
+
+    /**
+     * @brief Writes a new ledger object.
+     *
+     * @param key The key to write the ledger object under
+     * @param seq The ledger sequence to write for
+     * @param blob The data to write
+     */
+    virtual void
+    writeLedgerObject(std::string&& key, std::uint32_t seq, std::string&& blob);
+
+    /**
+     * @brief Writes a new transaction.
+     *
+     * @param hash The hash of the transaction
+     * @param seq The ledger sequence to write for
+     * @param date The timestamp of the entry
+     * @param transaction The transaction data to write
+     * @param metadata The metadata to write
+     */
+    virtual void
+    writeTransaction(
+        std::string&& hash,
+        std::uint32_t seq,
+        std::uint32_t date,
+        std::string&& transaction,
+        std::string&& metadata
+    ) = 0;
+
+    /**
+     * @brief Writes NFTs to the database.
+     *
+     * @param data A vector of NFTsData objects representing the NFTs
+     */
+    virtual void
+    writeNFTs(std::vector<NFTsData> const& data) = 0;
+
+    /**
+     * @brief Write a new set of account transactions.
+     *
+     * @param data A vector of AccountTransactionsData objects representing the account transactions
+     */
+    virtual void
+    writeAccountTransactions(std::vector<AccountTransactionsData> data) = 0;
+
+    /**
+     * @brief Write NFTs transactions.
+     *
+     * @param data A vector of NFTTransactionsData objects
+     */
+    virtual void
+    writeNFTTransactions(std::vector<NFTTransactionsData> const& data) = 0;
+
+    /**
+     * @brief Write a new successor.
+     *
+     * @param key Key of the object that the passed successor will be the successor for
+     * @param seq The ledger sequence to write for
+     * @param successor The successor data to write
+     */
+    virtual void
+    writeSuccessor(std::string&& key, std::uint32_t seq, std::string&& successor) = 0;
+
+    /**
+     * @brief Starts a write transaction with the DB. No-op for cassandra.
+     *
+     * Note: Can potentially be deprecated and removed.
+     */
+    virtual void
+    startWrites() const = 0;
+
+    /**
+     * @brief Tells database we finished writing all data for a specific ledger.
+     *
+     * Uses doFinishWrites to synchronize with the pending writes.
+     *
+     * @param ledgerSequence The ledger sequence to finish writing for
+     * @return true on success; false otherwise
+     */
+    bool
+    finishWrites(std::uint32_t ledgerSequence);
+
+    /**
+     * @return true if database is overwhelmed; false otherwise
+     */
+    virtual bool
+    isTooBusy() const = 0;
+
+    /**
+     * @return json object containing backend usage statistics
+     */
+    virtual boost::json::object
+    stats() const = 0;
+
+private:
+    virtual void
+    doWriteLedgerObject(std::string&& key, std::uint32_t seq, std::string&& blob) = 0;
+
+    virtual bool
+    doFinishWrites() = 0;
+};
+
+}  // namespace data
+using BackendInterface = data::BackendInterface;

src/data/DBHelpers.hpp

@@ -17,29 +17,38 @@
 */
 //==============================================================================
 
+/** @file */
 #pragma once
 
-#include <ripple/basics/Log.h>
-#include <ripple/basics/StringUtilities.h>
-#include <ripple/ledger/ReadView.h>
-#include <ripple/protocol/SField.h>
-#include <ripple/protocol/STAccount.h>
-#include <ripple/protocol/TxMeta.h>
+#include "util/Assert.hpp"
 
 #include <boost/container/flat_set.hpp>
+#include <ripple/basics/Blob.h>
+#include <ripple/basics/Log.h>
+#include <ripple/basics/StringUtilities.h>
+#include <ripple/basics/base_uint.h>
+#include <ripple/protocol/AccountID.h>
+#include <ripple/protocol/SField.h>
+#include <ripple/protocol/STAccount.h>
+#include <ripple/protocol/STLedgerEntry.h>
+#include <ripple/protocol/Serializer.h>
+#include <ripple/protocol/TxMeta.h>
 
-#include <backend/Types.h>
+#include <cstddef>
+#include <cstdint>
+#include <optional>
+#include <string>
 
-/// Struct used to keep track of what to write to
-/// account_transactions/account_tx tables
-struct AccountTransactionsData
-{
+/**
+ * @brief Struct used to keep track of what to write to account_transactions/account_tx tables.
+ */
+struct AccountTransactionsData {
     boost::container::flat_set<ripple::AccountID> accounts;
-    std::uint32_t ledgerSequence;
-    std::uint32_t transactionIndex;
+    std::uint32_t ledgerSequence{};
+    std::uint32_t transactionIndex{};
     ripple::uint256 txHash;
 
-    AccountTransactionsData(ripple::TxMeta& meta, ripple::uint256 const& txHash, beast::Journal& j)
+    AccountTransactionsData(ripple::TxMeta& meta, ripple::uint256 const& txHash)
         : accounts(meta.getAffectedAccounts())
         , ledgerSequence(meta.getLgrSeq())
         , transactionIndex(meta.getIndex())
@@ -50,10 +59,12 @@ struct AccountTransactionsData
     AccountTransactionsData() = default;
 };
 
-/// Represents a link from a tx to an NFT that was targeted/modified/created
-/// by it. Gets written to nf_token_transactions table and the like.
-struct NFTTransactionsData
-{
+/**
+ * @brief Represents a link from a tx to an NFT that was targeted/modified/created by it.
+ *
+ * Gets written to nf_token_transactions table and the like.
+ */
+struct NFTTransactionsData {
     ripple::uint256 tokenID;
     std::uint32_t ledgerSequence;
     std::uint32_t transactionIndex;
@@ -65,10 +76,12 @@ struct NFTTransactionsData
     }
 };
 
-/// Represents an NFT state at a particular ledger. Gets written to nf_tokens
-/// table and the like.
-struct NFTsData
-{
+/**
+ * @brief Represents an NFT state at a particular ledger.
+ *
+ * Gets written to nf_tokens table and the like.
+ */
+struct NFTsData {
     ripple::uint256 tokenID;
     std::uint32_t ledgerSequence;
 
@@ -100,7 +113,8 @@ struct NFTsData
         ripple::uint256 const& tokenID,
         ripple::AccountID const& owner,
         ripple::Blob const& uri,
-        ripple::TxMeta const& meta)
+        ripple::TxMeta const& meta
+    )
         : tokenID(tokenID), ledgerSequence(meta.getLgrSeq()), transactionIndex(meta.getIndex()), owner(owner), uri(uri)
     {
     }
@@ -126,41 +140,68 @@ struct NFTsData
         ripple::uint256 const& tokenID,
         std::uint32_t const ledgerSequence,
         ripple::AccountID const& owner,
-        ripple::Blob const& uri)
+        ripple::Blob const& uri
+    )
         : tokenID(tokenID), ledgerSequence(ledgerSequence), owner(owner), uri(uri)
     {
     }
 };
 
+/**
+ * @brief Check whether the supplied object is an offer.
+ *
+ * @param object The object to check
+ * @return true if the object is an offer; false otherwise
+ */
 template <class T>
 inline bool
 isOffer(T const& object)
 {
-    short offer_bytes = (object[1] << 8) | object[2];
-    return offer_bytes == 0x006f;
+    static constexpr short OFFER_OFFSET = 0x006f;
+    static constexpr short SHIFT = 8;
+
+    short offer_bytes = (object[1] << SHIFT) | object[2];
+    return offer_bytes == OFFER_OFFSET;
 }
 
+/**
+ * @brief Check whether the supplied hex represents an offer object.
+ *
+ * @param object The object to check
+ * @return true if the object is an offer; false otherwise
+ */
 template <class T>
 inline bool
 isOfferHex(T const& object)
 {
     auto blob = ripple::strUnHex(4, object.begin(), object.begin() + 4);
     if (blob)
-    {
-        short offer_bytes = ((*blob)[1] << 8) | (*blob)[2];
-        return offer_bytes == 0x006f;
-    }
+        return isOffer(*blob);
     return false;
 }
 
+/**
+ * @brief Check whether the supplied object is a dir node.
+ *
+ * @param object The object to check
+ * @return true if the object is a dir node; false otherwise
+ */
 template <class T>
 inline bool
 isDirNode(T const& object)
 {
-    short spaceKey = (object.data()[1] << 8) | object.data()[2];
-    return spaceKey == 0x0064;
+    static constexpr short DIR_NODE_SPACE_KEY = 0x0064;
+    short const spaceKey = (object.data()[1] << 8) | object.data()[2];
+    return spaceKey == DIR_NODE_SPACE_KEY;
 }
 
+/**
+ * @brief Check whether the supplied object is a book dir.
+ *
+ * @param key The key into the object
+ * @param object The object to check
+ * @return true if the object is a book dir; false otherwise
+ */
 template <class T, class R>
 inline bool
 isBookDir(T const& key, R const& object)
@@ -172,55 +213,55 @@ isBookDir(T const& key, R const& object)
     return !sle[~ripple::sfOwner].has_value();
 }
 
+/**
+ * @brief Get the book out of an offer object.
+ *
+ * @param offer The offer to get the book for
+ * @return Book as ripple::uint256
+ */
 template <class T>
 inline ripple::uint256
 getBook(T const& offer)
 {
     ripple::SerialIter it{offer.data(), offer.size()};
-    ripple::SLE sle{it, {}};
+    ripple::SLE const sle{it, {}};
     ripple::uint256 book = sle.getFieldH256(ripple::sfBookDirectory);
+
     return book;
 }
 
+/**
+ * @brief Get the book base.
+ *
+ * @param key The key to get the book base out of
+ * @return Book base as ripple::uint256
+ */
 template <class T>
 inline ripple::uint256
 getBookBase(T const& key)
 {
-    assert(key.size() == ripple::uint256::size());
+    static constexpr size_t KEY_SIZE = 24;
+
+    ASSERT(key.size() == ripple::uint256::size(), "Invalid key size {}", key.size());
+
     ripple::uint256 ret;
-    for (size_t i = 0; i < 24; ++i)
-    {
+    for (size_t i = 0; i < KEY_SIZE; ++i)
         ret.data()[i] = key.data()[i];
-    }
+
     return ret;
 }
 
-inline ripple::LedgerInfo
-deserializeHeader(ripple::Slice data)
-{
-    ripple::SerialIter sit(data.data(), data.size());
-
-    ripple::LedgerInfo info;
-
-    info.seq = sit.get32();
-    info.drops = sit.get64();
-    info.parentHash = sit.get256();
-    info.txHash = sit.get256();
-    info.accountHash = sit.get256();
-    info.parentCloseTime = ripple::NetClock::time_point{ripple::NetClock::duration{sit.get32()}};
-    info.closeTime = ripple::NetClock::time_point{ripple::NetClock::duration{sit.get32()}};
-    info.closeTimeResolution = ripple::NetClock::duration{sit.get8()};
-    info.closeFlags = sit.get8();
-
-    info.hash = sit.get256();
-
-    return info;
-}
-
+/**
+ * @brief Stringify a ripple::uint256.
+ *
+ * @param input The input value
+ * @return The input value as a string
+ */
 inline std::string
-uint256ToString(ripple::uint256 const& uint)
+uint256ToString(ripple::uint256 const& input)
 {
-    return {reinterpret_cast<const char*>(uint.data()), uint.size()};
+    return {reinterpret_cast<char const*>(input.data()), ripple::uint256::size()};
 }
 
+/** @brief The ripple epoch start timestamp. Midnight on 1st January 2000. */
 static constexpr std::uint32_t rippleEpochStart = 946684800;

src/data/LedgerCache.cpp

@@ -17,74 +17,97 @@
 */
 //==============================================================================
 
-#include <backend/SimpleCache.h>
-namespace Backend {
+#include "data/LedgerCache.hpp"
+
+#include "data/Types.hpp"
+#include "util/Assert.hpp"
+
+#include <ripple/basics/base_uint.h>
+
+#include <cstddef>
+#include <cstdint>
+#include <mutex>
+#include <optional>
+#include <shared_mutex>
+#include <vector>
+
+namespace data {
 
 uint32_t
-SimpleCache::latestLedgerSequence() const
+LedgerCache::latestLedgerSequence() const
 {
-    std::shared_lock lck{mtx_};
+    std::shared_lock const lck{mtx_};
     return latestSeq_;
 }
 
 void
-SimpleCache::update(std::vector<LedgerObject> const& objs, uint32_t seq, bool isBackground)
+LedgerCache::waitUntilCacheContainsSeq(uint32_t seq)
+{
+    if (disabled_)
+        return;
+    std::unique_lock lock(mtx_);
+    cv_.wait(lock, [this, seq] { return latestSeq_ >= seq; });
+    return;
+}
+
+void
+LedgerCache::update(std::vector<LedgerObject> const& objs, uint32_t seq, bool isBackground)
 {
     if (disabled_)
         return;
 
     {
-        std::scoped_lock lck{mtx_};
-        if (seq > latestSeq_)
-        {
-            assert(seq == latestSeq_ + 1 || latestSeq_ == 0);
+        std::scoped_lock const lck{mtx_};
+        if (seq > latestSeq_) {
+            ASSERT(
+                seq == latestSeq_ + 1 || latestSeq_ == 0,
+                "New sequense must be either next or first. seq = {}, latestSeq_ = {}",
+                seq,
+                latestSeq_
+            );
             latestSeq_ = seq;
         }
-        for (auto const& obj : objs)
-        {
-            if (obj.blob.size())
-            {
-                if (isBackground && deletes_.count(obj.key))
+        for (auto const& obj : objs) {
+            if (!obj.blob.empty()) {
+                if (isBackground && deletes_.contains(obj.key))
                     continue;
 
                 auto& e = map_[obj.key];
-                if (seq > e.seq)
-                {
+                if (seq > e.seq) {
                     e = {seq, obj.blob};
                 }
-            }
-            else
-            {
+            } else {
                 map_.erase(obj.key);
                 if (!full_ && !isBackground)
                     deletes_.insert(obj.key);
             }
         }
+        cv_.notify_all();
     }
 }
 
 std::optional<LedgerObject>
-SimpleCache::getSuccessor(ripple::uint256 const& key, uint32_t seq) const
+LedgerCache::getSuccessor(ripple::uint256 const& key, uint32_t seq) const
 {
     if (!full_)
         return {};
-    std::shared_lock{mtx_};
-    successorReqCounter_++;
+    std::shared_lock const lck{mtx_};
+    ++successorReqCounter_.get();
     if (seq != latestSeq_)
         return {};
     auto e = map_.upper_bound(key);
     if (e == map_.end())
         return {};
-    successorHitCounter_++;
+    ++successorHitCounter_.get();
     return {{e->first, e->second.blob}};
 }
 
 std::optional<LedgerObject>
-SimpleCache::getPredecessor(ripple::uint256 const& key, uint32_t seq) const
+LedgerCache::getPredecessor(ripple::uint256 const& key, uint32_t seq) const
 {
     if (!full_)
         return {};
-    std::shared_lock lck{mtx_};
+    std::shared_lock const lck{mtx_};
     if (seq != latestSeq_)
         return {};
     auto e = map_.lower_bound(key);
@@ -93,62 +116,67 @@ SimpleCache::getPredecessor(ripple::uint256 const& key, uint32_t seq) const
     --e;
     return {{e->first, e->second.blob}};
 }
+
 std::optional<Blob>
-SimpleCache::get(ripple::uint256 const& key, uint32_t seq) const
+LedgerCache::get(ripple::uint256 const& key, uint32_t seq) const
 {
-    std::shared_lock lck{mtx_};
+    std::shared_lock const lck{mtx_};
     if (seq > latestSeq_)
         return {};
-    objectReqCounter_++;
+    ++objectReqCounter_.get();
     auto e = map_.find(key);
     if (e == map_.end())
         return {};
     if (seq < e->second.seq)
         return {};
-    objectHitCounter_++;
+    ++objectHitCounter_.get();
     return {e->second.blob};
 }
 
 void
-SimpleCache::setDisabled()
+LedgerCache::setDisabled()
 {
     disabled_ = true;
 }
 
 void
-SimpleCache::setFull()
+LedgerCache::setFull()
 {
     if (disabled_)
         return;
 
     full_ = true;
-    std::scoped_lock lck{mtx_};
+    std::scoped_lock const lck{mtx_};
     deletes_.clear();
 }
 
 bool
-SimpleCache::isFull() const
+LedgerCache::isFull() const
 {
     return full_;
 }
+
 size_t
-SimpleCache::size() const
+LedgerCache::size() const
 {
-    std::shared_lock lck{mtx_};
+    std::shared_lock const lck{mtx_};
     return map_.size();
 }
+
 float
-SimpleCache::getObjectHitRate() const
+LedgerCache::getObjectHitRate() const
 {
-    if (!objectReqCounter_)
+    if (objectReqCounter_.get().value() == 0u)
         return 1;
-    return ((float)objectHitCounter_) / objectReqCounter_;
+    return static_cast<float>(objectHitCounter_.get().value()) / objectReqCounter_.get().value();
 }
+
 float
-SimpleCache::getSuccessorHitRate() const
+LedgerCache::getSuccessorHitRate() const
 {
-    if (!successorReqCounter_)
+    if (successorReqCounter_.get().value() == 0u)
         return 1;
-    return ((float)successorHitCounter_) / successorReqCounter_;
+    return static_cast<float>(successorHitCounter_.get().value()) / successorReqCounter_.get().value();
 }
-}  // namespace Backend
+
+}  // namespace data

src/data/LedgerCache.hpp

@@ -0,0 +1,180 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of clio: https://github.com/XRPLF/clio
+    Copyright (c) 2022, the clio developers.
+
+    Permission to use, copy, modify, and distribute this software for any
+    purpose with or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL,  DIRECT,  INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+
+#pragma once
+
+#include "data/Types.hpp"
+#include "util/prometheus/Counter.hpp"
+#include "util/prometheus/Label.hpp"
+#include "util/prometheus/Prometheus.hpp"
+
+#include <ripple/basics/base_uint.h>
+#include <ripple/basics/hardened_hash.h>
+
+#include <atomic>
+#include <condition_variable>
+#include <cstddef>
+#include <cstdint>
+#include <functional>
+#include <map>
+#include <optional>
+#include <shared_mutex>
+#include <unordered_set>
+#include <vector>
+
+namespace data {
+
+/**
+ * @brief Cache for an entire ledger.
+ */
+class LedgerCache {
+    struct CacheEntry {
+        uint32_t seq = 0;
+        Blob blob;
+    };
+
+    // counters for fetchLedgerObject(s) hit rate
+    std::reference_wrapper<util::prometheus::CounterInt> objectReqCounter_{PrometheusService::counterInt(
+        "ledger_cache_counter_total_number",
+        util::prometheus::Labels({{"type", "request"}, {"fetch", "ledger_objects"}}),
+        "LedgerCache statistics"
+    )};
+    std::reference_wrapper<util::prometheus::CounterInt> objectHitCounter_{PrometheusService::counterInt(
+        "ledger_cache_counter_total_number",
+        util::prometheus::Labels({{"type", "cache_hit"}, {"fetch", "ledger_objects"}})
+    )};
+
+    // counters for fetchSuccessorKey hit rate
+    std::reference_wrapper<util::prometheus::CounterInt> successorReqCounter_{PrometheusService::counterInt(
+        "ledger_cache_counter_total_number",
+        util::prometheus::Labels({{"type", "request"}, {"fetch", "successor_key"}}),
+        "ledgerCache"
+    )};
+    std::reference_wrapper<util::prometheus::CounterInt> successorHitCounter_{PrometheusService::counterInt(
+        "ledger_cache_counter_total_number",
+        util::prometheus::Labels({{"type", "cache_hit"}, {"fetch", "successor_key"}})
+    )};
+
+    std::map<ripple::uint256, CacheEntry> map_;
+
+    mutable std::shared_mutex mtx_;
+    std::condition_variable_any cv_;
+    uint32_t latestSeq_ = 0;
+    std::atomic_bool full_ = false;
+    std::atomic_bool disabled_ = false;
+
+    // temporary set to prevent background thread from writing already deleted data. not used when cache is full
+    std::unordered_set<ripple::uint256, ripple::hardened_hash<>> deletes_;
+
+public:
+    /**
+     * @brief Update the cache with new ledger objects.
+     *
+     * @param blobs The ledger objects to update cache with
+     * @param seq The sequence to update cache for
+     * @param isBackground Should be set to true when writing old data from a background thread
+     */
+    void
+    update(std::vector<LedgerObject> const& objs, uint32_t seq, bool isBackground = false);
+
+    /**
+     * @brief Fetch a cached object by its key and sequence number.
+     *
+     * @param key The key to fetch for
+     * @param seq The sequence to fetch for
+     * @return If found in cache, will return the cached Blob; otherwise nullopt is returned
+     */
+    std::optional<Blob>
+    get(ripple::uint256 const& key, uint32_t seq) const;
+
+    /**
+     * @brief Gets a cached successor.
+     *
+     * Note: This function always returns std::nullopt when @ref isFull() returns false.
+     *
+     * @param key The key to fetch for
+     * @param seq The sequence to fetch for
+     * @return If found in cache, will return the cached successor; otherwise nullopt is returned
+     */
+    std::optional<LedgerObject>
+    getSuccessor(ripple::uint256 const& key, uint32_t seq) const;
+
+    /**
+     * @brief Gets a cached predcessor.
+     *
+     * Note: This function always returns std::nullopt when @ref isFull() returns false.
+     *
+     * @param key The key to fetch for
+     * @param seq The sequence to fetch for
+     * @return If found in cache, will return the cached predcessor; otherwise nullopt is returned
+     */
+    std::optional<LedgerObject>
+    getPredecessor(ripple::uint256 const& key, uint32_t seq) const;
+
+    /**
+     * @brief Disables the cache.
+     */
+    void
+    setDisabled();
+
+    /**
+     * @brief Sets the full flag to true.
+     *
+     * This is used when cache loaded in its entirety at startup of the application. This can be either loaded from DB,
+     * populated together with initial ledger download (on first run) or downloaded from a peer node (specified in
+     * config).
+     */
+    void
+    setFull();
+
+    /**
+     * @return The latest ledger sequence for which cache is available.
+     */
+    uint32_t
+    latestLedgerSequence() const;
+
+    /**
+     * @return true if the cache has all data for the most recent ledger; false otherwise
+     */
+    bool
+    isFull() const;
+
+    /**
+     * @return The total size of the cache.
+     */
+    size_t
+    size() const;
+
+    /**
+     * @return A number representing the success rate of hitting an object in the cache versus missing it.
+     */
+    float
+    getObjectHitRate() const;
+
+    /**
+     * @return A number representing the success rate of hitting a successor in the cache versus missing it.
+     */
+    float
+    getSuccessorHitRate() const;
+
+    void
+    waitUntilCacheContainsSeq(uint32_t seq);
+};
+
+}  // namespace data

src/data/README.md

@@ -1,4 +1,5 @@
-# Clio Backend
+# Backend
+
 ## Background
 The backend of Clio is responsible for handling the proper reading and writing of past ledger data from and to a given database. As of right now, Cassandra and ScyllaDB are the only supported databases that are production-ready. Support for database types can be easily extended by creating new implementations which implements the virtual methods of `BackendInterface.h`. Then, use the Factory Object Design Pattern to simply add logic statements to `BackendFactory.h` that return the new database interface for a specific `type` in Clio's configuration file. 
 

src/data/Types.hpp

@@ -21,51 +21,60 @@
 
 #include <ripple/basics/base_uint.h>
 #include <ripple/protocol/AccountID.h>
+
+#include <cstdint>
 #include <optional>
-#include <string>
+#include <string_view>
+#include <tuple>
+#include <utility>
 #include <vector>
 
-namespace Backend {
-
-// *** return types
+namespace data {
 
 using Blob = std::vector<unsigned char>;
 
-struct LedgerObject
-{
+/**
+ * @brief Represents an object in the ledger.
+ */
+struct LedgerObject {
     ripple::uint256 key;
     Blob blob;
+
     bool
-    operator==(const LedgerObject& other) const
+    operator==(LedgerObject const& other) const
     {
         return key == other.key && blob == other.blob;
     }
 };
 
-struct LedgerPage
-{
+/**
+ * @brief Represents a page of LedgerObjects.
+ */
+struct LedgerPage {
     std::vector<LedgerObject> objects;
     std::optional<ripple::uint256> cursor;
 };
-struct BookOffersPage
-{
+
+/**
+ * @brief Represents a page of book offer objects.
+ */
+struct BookOffersPage {
     std::vector<LedgerObject> offers;
     std::optional<ripple::uint256> cursor;
 };
-struct TransactionAndMetadata
-{
+
+/**
+ * @brief Represents a transaction and its metadata bundled together.
+ */
+struct TransactionAndMetadata {
     Blob transaction;
     Blob metadata;
     std::uint32_t ledgerSequence = 0;
     std::uint32_t date = 0;
 
     TransactionAndMetadata() = default;
-    TransactionAndMetadata(
-        Blob const& transaction,
-        Blob const& metadata,
-        std::uint32_t ledgerSequence,
-        std::uint32_t date)
-        : transaction{transaction}, metadata{metadata}, ledgerSequence{ledgerSequence}, date{date}
+    TransactionAndMetadata(Blob transaction, Blob metadata, std::uint32_t ledgerSequence, std::uint32_t date)
+        : transaction{std::move(transaction)}, metadata{std::move(metadata)}, ledgerSequence{ledgerSequence}, date{date}
     {
     }
 
@@ -78,17 +87,19 @@ struct TransactionAndMetadata
     }
 
     bool
-    operator==(const TransactionAndMetadata& other) const
+    operator==(TransactionAndMetadata const& other) const
     {
         return transaction == other.transaction && metadata == other.metadata &&
             ledgerSequence == other.ledgerSequence && date == other.date;
     }
 };
 
-struct TransactionsCursor
-{
-    std::uint32_t ledgerSequence;
-    std::uint32_t transactionIndex;
+/**
+ * @brief Represents a cursor into the transactions table.
+ */
+struct TransactionsCursor {
+    std::uint32_t ledgerSequence = 0;
+    std::uint32_t transactionIndex = 0;
 
     TransactionsCursor() = default;
     TransactionsCursor(std::uint32_t ledgerSequence, std::uint32_t transactionIndex)
@@ -101,9 +112,6 @@ struct TransactionsCursor
     {
     }
 
-    TransactionsCursor&
-    operator=(TransactionsCursor const&) = default;
-
     bool
     operator==(TransactionsCursor const& other) const = default;
 
@@ -114,27 +122,31 @@ struct TransactionsCursor
     }
 };
 
-struct TransactionsAndCursor
-{
+/**
+ * @brief Represests a bundle of transactions with metadata and a cursor to the next page.
+ */
+struct TransactionsAndCursor {
     std::vector<TransactionAndMetadata> txns;
     std::optional<TransactionsCursor> cursor;
 };
 
-struct NFT
-{
+/**
+ * @brief Represents a NFToken.
+ */
+struct NFT {
     ripple::uint256 tokenID;
-    std::uint32_t ledgerSequence;
+    std::uint32_t ledgerSequence{};
     ripple::AccountID owner;
     Blob uri;
-    bool isBurned;
+    bool isBurned{};
 
     NFT() = default;
     NFT(ripple::uint256 const& tokenID,
         std::uint32_t ledgerSequence,
         ripple::AccountID const& owner,
-        Blob const& uri,
+        Blob uri,
         bool isBurned)
-        : tokenID{tokenID}, ledgerSequence{ledgerSequence}, owner{owner}, uri{uri}, isBurned{isBurned}
+        : tokenID{tokenID}, ledgerSequence{ledgerSequence}, owner{owner}, uri{std::move(uri)}, isBurned{isBurned}
     {
     }
 
@@ -143,9 +155,8 @@ struct NFT
     {
     }
 
-    // clearly two tokens are the same if they have the same ID, but this
-    // struct stores the state of a given token at a given ledger sequence, so
-    // we also need to compare with ledgerSequence
+    // clearly two tokens are the same if they have the same ID, but this struct stores the state of a given token at a
+    // given ledger sequence, so we also need to compare with ledgerSequence.
     bool
     operator==(NFT const& other) const
     {
@@ -153,12 +164,21 @@ struct NFT
     }
 };
 
-struct LedgerRange
-{
-    std::uint32_t minSequence;
-    std::uint32_t maxSequence;
+struct NFTsAndCursor {
+    std::vector<NFT> nfts;
+    std::optional<ripple::uint256> cursor;
 };
+
+/**
+ * @brief Stores a range of sequences as a min and max pair.
+ */
+struct LedgerRange {
+    std::uint32_t minSequence = 0;
+    std::uint32_t maxSequence = 0;
+};
+
 constexpr ripple::uint256 firstKey{"0000000000000000000000000000000000000000000000000000000000000000"};
 constexpr ripple::uint256 lastKey{"FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"};
 constexpr ripple::uint256 hi192{"0000000000000000000000000000000000000000000000001111111111111111"};
-}  // namespace Backend
+
+}  // namespace data

src/data/cassandra/Concepts.hpp

@@ -0,0 +1,131 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of clio: https://github.com/XRPLF/clio
+    Copyright (c) 2023, the clio developers.
+
+    Permission to use, copy, modify, and distribute this software for any
+    purpose with or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL,  DIRECT,  INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+
+#pragma once
+
+#include "data/cassandra/Types.hpp"
+
+#include <boost/asio/io_context.hpp>
+#include <boost/asio/spawn.hpp>
+#include <boost/json.hpp>
+#include <boost/json/object.hpp>
+
+#include <chrono>
+#include <concepts>
+#include <cstdint>
+#include <optional>
+#include <string>
+#include <utility>
+#include <vector>
+
+namespace data::cassandra {
+
+/**
+ * @brief The requirements of a settings provider.
+ */
+template <typename T>
+concept SomeSettingsProvider = requires(T a) {
+    {
+        a.getSettings()
+    } -> std::same_as<Settings>;
+    {
+        a.getKeyspace()
+    } -> std::same_as<std::string>;
+    {
+        a.getTablePrefix()
+    } -> std::same_as<std::optional<std::string>>;
+    {
+        a.getReplicationFactor()
+    } -> std::same_as<uint16_t>;
+    {
+        a.getTtl()
+    } -> std::same_as<uint16_t>;
+};
+
+/**
+ * @brief The requirements of an execution strategy.
+ */
+template <typename T>
+concept SomeExecutionStrategy = requires(
+    T a,
+    Settings settings,
+    Handle handle,
+    Statement statement,
+    std::vector<Statement> statements,
+    PreparedStatement prepared,
+    boost::asio::yield_context token
+) {
+    {
+        T(settings, handle)
+    };
+    {
+        a.sync()
+    } -> std::same_as<void>;
+    {
+        a.isTooBusy()
+    } -> std::same_as<bool>;
+    {
+        a.writeSync(statement)
+    } -> std::same_as<ResultOrError>;
+    {
+        a.writeSync(prepared)
+    } -> std::same_as<ResultOrError>;
+    {
+        a.write(prepared)
+    } -> std::same_as<void>;
+    {
+        a.write(std::move(statements))
+    } -> std::same_as<void>;
+    {
+        a.read(token, prepared)
+    } -> std::same_as<ResultOrError>;
+    {
+        a.read(token, statement)
+    } -> std::same_as<ResultOrError>;
+    {
+        a.read(token, statements)
+    } -> std::same_as<ResultOrError>;
+    {
+        a.readEach(token, statements)
+    } -> std::same_as<std::vector<Result>>;
+    {
+        a.stats()
+    } -> std::same_as<boost::json::object>;
+};
+
+/**
+ * @brief The requirements of a retry policy.
+ */
+template <typename T>
+concept SomeRetryPolicy = requires(T a, boost::asio::io_context ioc, CassandraError err, uint32_t attempt) {
+    {
+        T(ioc)
+    };
+    {
+        a.shouldRetry(err)
+    } -> std::same_as<bool>;
+    {
+        a.retry([]() {})
+    } -> std::same_as<void>;
+    {
+        a.calculateDelay(attempt)
+    } -> std::same_as<std::chrono::milliseconds>;
+};
+
+}  // namespace data::cassandra

src/data/cassandra/Error.hpp

@@ -21,34 +21,38 @@
 
 #include <cassandra.h>
 
+#include <cstdint>
+#include <ostream>
 #include <string>
+#include <utility>
 
-namespace Backend::Cassandra {
+namespace data::cassandra {
 
 /**
- * @brief A simple container for both error message and error code
+ * @brief A simple container for both error message and error code.
  */
-class CassandraError
-{
+class CassandraError {
     std::string message_;
-    uint32_t code_;
+    uint32_t code_{};
 
 public:
     CassandraError() = default;  // default constructible required by Expected
-    CassandraError(std::string message, uint32_t code) : message_{message}, code_{code}
+    CassandraError(std::string message, uint32_t code) : message_{std::move(message)}, code_{code}
     {
     }
 
     template <typename T>
     friend std::string
-    operator+(T const& lhs, CassandraError const& rhs) requires std::is_convertible_v<T, std::string>
+    operator+(T const& lhs, CassandraError const& rhs)
+        requires std::is_convertible_v<T, std::string>
     {
         return lhs + rhs.message();
     }
 
     template <typename T>
     friend bool
-    operator==(T const& lhs, CassandraError const& rhs) requires std::is_convertible_v<T, std::string>
+    operator==(T const& lhs, CassandraError const& rhs)
+        requires std::is_convertible_v<T, std::string>
     {
         return lhs == rhs.message();
     }
@@ -67,28 +71,38 @@ public:
         return os;
     }
 
+    /**
+     * @return The final error message as a std::string
+     */
     std::string
     message() const
     {
         return message_;
     }
 
+    /**
+     * @return The error code
+     */
     uint32_t
     code() const
     {
         return code_;
     }
 
+    /**
+     * @return true if the wrapped error is considered a timeout; false otherwise
+     */
     bool
     isTimeout() const
     {
-        if (code_ == CASS_ERROR_LIB_NO_HOSTS_AVAILABLE or code_ == CASS_ERROR_LIB_REQUEST_TIMED_OUT or
+        return code_ == CASS_ERROR_LIB_NO_HOSTS_AVAILABLE or code_ == CASS_ERROR_LIB_REQUEST_TIMED_OUT or
             code_ == CASS_ERROR_SERVER_UNAVAILABLE or code_ == CASS_ERROR_SERVER_OVERLOADED or
-            code_ == CASS_ERROR_SERVER_READ_TIMEOUT)
-            return true;
-        return false;
+            code_ == CASS_ERROR_SERVER_READ_TIMEOUT;
     }
 
+    /**
+     * @return true if the wrapped error is an invalid query; false otherwise
+     */
     bool
     isInvalidQuery() const
     {
@@ -96,4 +110,4 @@ public:
     }
 };
 
-}  // namespace Backend::Cassandra
+}  // namespace data::cassandra

src/data/cassandra/Handle.cpp

@@ -17,9 +17,20 @@
 */
 //==============================================================================
 
-#include <backend/cassandra/Handle.h>
+#include "data/cassandra/Handle.hpp"
 
-namespace Backend::Cassandra {
+#include "data/cassandra/Types.hpp"
+
+#include <cassandra.h>
+
+#include <functional>
+#include <stdexcept>
+#include <string>
+#include <string_view>
+#include <utility>
+#include <vector>
+
+namespace data::cassandra {
 
 Handle::Handle(Settings clusterSettings) : cluster_{clusterSettings}
 {
@@ -88,17 +99,17 @@ std::vector<Handle::FutureType>
 Handle::asyncExecuteEach(std::vector<Statement> const& statements) const
 {
     std::vector<Handle::FutureType> futures;
+    futures.reserve(statements.size());
     for (auto const& statement : statements)
-        futures.push_back(cass_session_execute(session_, statement));
+        futures.emplace_back(cass_session_execute(session_, statement));
     return futures;
 }
 
 Handle::MaybeErrorType
 Handle::executeEach(std::vector<Statement> const& statements) const
 {
-    for (auto futures = asyncExecuteEach(statements); auto const& future : futures)
-    {
-        if (auto const rc = future.await(); not rc)
+    for (auto futures = asyncExecuteEach(statements); auto const& future : futures) {
+        if (auto rc = future.await(); not rc)
             return rc;
     }
 
@@ -145,11 +156,12 @@ Handle::asyncExecute(std::vector<Statement> const& statements, std::function<voi
 Handle::PreparedStatementType
 Handle::prepare(std::string_view query) const
 {
-    Handle::FutureType future = cass_session_prepare(session_, query.data());
-    if (auto const rc = future.await(); rc)
+    Handle::FutureType const future = cass_session_prepare(session_, query.data());
+    auto const rc = future.await();
+    if (rc)
         return cass_future_get_prepared(future);
-    else
-        throw std::runtime_error(rc.error().message());
+
+    throw std::runtime_error(rc.error().message());
 }
 
-}  // namespace Backend::Cassandra
+}  // namespace data::cassandra

src/data/cassandra/Handle.hpp

@@ -19,31 +19,28 @@
 
 #pragma once
 
-#include <backend/cassandra/Error.h>
-#include <backend/cassandra/Types.h>
-#include <backend/cassandra/impl/Batch.h>
-#include <backend/cassandra/impl/Cluster.h>
-#include <backend/cassandra/impl/Future.h>
-#include <backend/cassandra/impl/ManagedObject.h>
-#include <backend/cassandra/impl/Result.h>
-#include <backend/cassandra/impl/Session.h>
-#include <backend/cassandra/impl/Statement.h>
-#include <util/Expected.h>
+#include "data/cassandra/Error.hpp"
+#include "data/cassandra/Types.hpp"
+#include "data/cassandra/impl/Batch.hpp"
+#include "data/cassandra/impl/Cluster.hpp"
+#include "data/cassandra/impl/Future.hpp"
+#include "data/cassandra/impl/ManagedObject.hpp"
+#include "data/cassandra/impl/Result.hpp"
+#include "data/cassandra/impl/Session.hpp"
+#include "data/cassandra/impl/Statement.hpp"
 
 #include <cassandra.h>
 
-#include <chrono>
-#include <compare>
-#include <iterator>
+#include <functional>
+#include <string_view>
 #include <vector>
 
-namespace Backend::Cassandra {
+namespace data::cassandra {
 
 /**
  * @brief Represents a handle to the cassandra database cluster
  */
-class Handle
-{
+class Handle {
     detail::Cluster cluster_;
     detail::Session session_;
 
@@ -57,28 +54,31 @@ public:
     using ResultType = Result;
 
     /**
-     * @brief Construct a new handle from a @ref Settings object
+     * @brief Construct a new handle from a @ref detail::Settings object.
+     *
+     * @param clusterSettings The settings to use
      */
     explicit Handle(Settings clusterSettings = Settings::defaultSettings());
 
     /**
-     * @brief Construct a new handle with default settings and only by setting
-     * the contact points
+     * @brief Construct a new handle with default settings and only by setting the contact points.
+     *
+     * @param contactPoints The contact points to use instead of settings
      */
     explicit Handle(std::string_view contactPoints);
 
     /**
-     * @brief Disconnects gracefully if possible
+     * @brief Disconnects gracefully if possible.
      */
     ~Handle();
 
     /**
-     * @brief Move is supported
+     * @brief Move is supported.
      */
     Handle(Handle&&) = default;
 
     /**
-     * @brief Connect to the cluster asynchronously
+     * @brief Connect to the cluster asynchronously.
      *
      * @return A future
      */
@@ -86,31 +86,37 @@ public:
     asyncConnect() const;
 
     /**
-     * @brief Synchonous version of the above
+     * @brief Synchonous version of the above.
      *
      * See @ref asyncConnect() const for how this works.
+     *
+     * @return Possibly an error
      */
     [[nodiscard]] MaybeErrorType
     connect() const;
 
     /**
-     * @brief Connect to the the specified keyspace asynchronously
+     * @brief Connect to the the specified keyspace asynchronously.
      *
+     * @param keyspace The keyspace to use
      * @return A future
      */
     [[nodiscard]] FutureType
     asyncConnect(std::string_view keyspace) const;
 
     /**
-     * @brief Synchonous version of the above
+     * @brief Synchonous version of the above.
      *
      * See @ref asyncConnect(std::string_view) const for how this works.
+     *
+     * @param keyspace The keyspace to use
+     * @return Possibly an error
      */
     [[nodiscard]] MaybeErrorType
     connect(std::string_view keyspace) const;
 
     /**
-     * @brief Disconnect from the cluster asynchronously
+     * @brief Disconnect from the cluster asynchronously.
      *
      * @return A future
      */
@@ -118,32 +124,40 @@ public:
     asyncDisconnect() const;
 
     /**
-     * @brief Synchonous version of the above
+     * @brief Synchonous version of the above.
      *
      * See @ref asyncDisconnect() const for how this works.
+     *
+     * @return Possibly an error
      */
     [[maybe_unused]] MaybeErrorType
     disconnect() const;
 
     /**
-     * @brief Reconnect to the the specified keyspace asynchronously
+     * @brief Reconnect to the the specified keyspace asynchronously.
      *
+     * @param keyspace The keyspace to use
      * @return A future
      */
     [[nodiscard]] FutureType
     asyncReconnect(std::string_view keyspace) const;
 
     /**
-     * @brief Synchonous version of the above
+     * @brief Synchonous version of the above.
      *
      * See @ref asyncReconnect(std::string_view) const for how this works.
+     *
+     * @param keyspace The keyspace to use
+     * @return Possibly an error
      */
     [[nodiscard]] MaybeErrorType
     reconnect(std::string_view keyspace) const;
 
     /**
-     * @brief Execute a simple query with optional args asynchronously
+     * @brief Execute a simple query with optional args asynchronously.
      *
+     * @param query The query to execute
+     * @param args The arguments to bind for execution
      * @return A future
      */
     template <typename... Args>
@@ -155,10 +169,13 @@ public:
     }
 
     /**
-     * @brief Synchonous version of the above
+     * @brief Synchonous version of the above.
      *
-     * See @ref asyncExecute(std::string_view, Args&&...) const for how this
-     * works.
+     * See asyncExecute(std::string_view, Args&&...) const for how this works.
+     *
+     * @param query The query to execute
+     * @param args The arguments to bind for execution
+     * @return The result or an error
      */
     template <typename... Args>
     [[maybe_unused]] ResultOrErrorType
@@ -168,30 +185,34 @@ public:
     }
 
     /**
-     * @brief Execute each of the statements asynchronously
+     * @brief Execute each of the statements asynchronously.
      *
-     * Batched version is not always the right option. Especially since it only
-     * supports INSERT, UPDATE and DELETE statements.
-     * This can be used as an alternative when statements need to execute in
-     * bulk.
+     * Batched version is not always the right option.
+     * Especially since it only supports INSERT, UPDATE and DELETE statements.
+     * This can be used as an alternative when statements need to execute in bulk.
      *
+     * @param statements The statements to execute
      * @return A vector of future objects
      */
     [[nodiscard]] std::vector<FutureType>
     asyncExecuteEach(std::vector<StatementType> const& statements) const;
 
     /**
-     * @brief Synchonous version of the above
+     * @brief Synchonous version of the above.
      *
-     * See @ref asyncExecuteEach(std::vector<StatementType> const&) const for
-     * how this works.
+     * See @ref asyncExecuteEach(std::vector<StatementType> const&) const for how this works.
+     *
+     * @param statements The statements to execute
+     * @return Possibly an error
      */
     [[maybe_unused]] MaybeErrorType
     executeEach(std::vector<StatementType> const& statements) const;
 
     /**
-     * @brief Execute a prepared statement with optional args asynchronously
+     * @brief Execute a prepared statement with optional args asynchronously.
      *
+     * @param statement The prepared statement to execute
+     * @param args The arguments to bind for execution
      * @return A future
      */
     template <typename... Args>
@@ -203,10 +224,13 @@ public:
     }
 
     /**
-     * @brief Synchonous version of the above
+     * @brief Synchonous version of the above.
      *
-     * See @ref asyncExecute(std::vector<StatementType> const&, Args&&...) const
-     * for how this works.
+     * See asyncExecute(std::vector<StatementType> const&, Args&&...) const for how this works.
+     *
+     * @param statement The prepared statement to bind and execute
+     * @param args The arguments to bind for execution
+     * @return The result or an error
      */
     template <typename... Args>
     [[maybe_unused]] ResultOrErrorType
@@ -216,61 +240,70 @@ public:
     }
 
     /**
-     * @brief Execute one (bound or simple) statements asynchronously
+     * @brief Execute one (bound or simple) statements asynchronously.
      *
+     * @param statement The statement to execute
      * @return A future
      */
     [[nodiscard]] FutureType
     asyncExecute(StatementType const& statement) const;
 
     /**
-     * @brief Execute one (bound or simple) statements asynchronously with a
-     * callback
+     * @brief Execute one (bound or simple) statements asynchronously with a callback.
      *
+     * @param statement The statement to execute
+     * @param cb The callback to execute when data is ready
      * @return A future that holds onto the callback provided
      */
     [[nodiscard]] FutureWithCallbackType
     asyncExecute(StatementType const& statement, std::function<void(ResultOrErrorType)>&& cb) const;
 
     /**
-     * @brief Synchonous version of the above
+     * @brief Synchonous version of the above.
      *
-     * See @ref asyncExecute(StatementType const&) const for how this
-     * works.
+     * See @ref asyncExecute(StatementType const&) const for how this works.
+     *
+     * @param statement The statement to execute
+     * @return The result or an error
      */
     [[maybe_unused]] ResultOrErrorType
     execute(StatementType const& statement) const;
 
     /**
-     * @brief Execute a batch of (bound or simple) statements asynchronously
+     * @brief Execute a batch of (bound or simple) statements asynchronously.
      *
+     * @param statements The statements to execute
      * @return A future
      */
     [[nodiscard]] FutureType
     asyncExecute(std::vector<StatementType> const& statements) const;
 
     /**
-     * @brief Synchonous version of the above
+     * @brief Synchonous version of the above.
      *
-     * See @ref asyncExecute(std::vector<StatementType> const&) const for how
-     * this works.
+     * See @ref asyncExecute(std::vector<StatementType> const&) const for how this works.
+     *
+     * @param statements The statements to execute
+     * @return Possibly an error
      */
     [[maybe_unused]] MaybeErrorType
     execute(std::vector<StatementType> const& statements) const;
 
     /**
-     * @brief Execute a batch of (bound or simple) statements asynchronously
-     * with a completion callback
+     * @brief Execute a batch of (bound or simple) statements asynchronously with a completion callback.
      *
+     * @param statements The statements to execute
+     * @param cb The callback to execute when data is ready
      * @return A future that holds onto the callback provided
      */
     [[nodiscard]] FutureWithCallbackType
     asyncExecute(std::vector<StatementType> const& statements, std::function<void(ResultOrErrorType)>&& cb) const;
 
     /**
-     * @brief Prepare a statement
+     * @brief Prepare a statement.
      *
-     * @return A @ref PreparedStatementType
+     * @param query
+     * @return A prepared statement
      * @throws std::runtime_error with underlying error description on failure
      */
     [[nodiscard]] PreparedStatementType
@@ -278,12 +311,13 @@ public:
 };
 
 /**
- * @brief Extracts the results into series of std::tuple<Types...> by creating a
- * simple wrapper with an STL input iterator inside.
+ * @brief Extracts the results into series of std::tuple<Types...> by creating a simple wrapper with an STL input
+ * iterator inside.
  *
  * You can call .begin() and .end() in order to iterate as usual.
- * This also means that you can use it in a range-based for or with some
- * algorithms.
+ * This also means that you can use it in a range-based for or with some algorithms.
+ *
+ * @param result The result to iterate
  */
 template <typename... Types>
 [[nodiscard]] detail::ResultExtractor<Types...>
@@ -292,4 +326,4 @@ extract(Handle::ResultType const& result)
     return {result};
 }
 
-}  // namespace Backend::Cassandra
+}  // namespace data::cassandra

src/data/cassandra/Schema.hpp

@@ -19,17 +19,20 @@
 
 #pragma once
 
-#include <backend/cassandra/Concepts.h>
-#include <backend/cassandra/Handle.h>
-#include <backend/cassandra/SettingsProvider.h>
-#include <backend/cassandra/Types.h>
-#include <config/Config.h>
-#include <log/Logger.h>
-#include <util/Expected.h>
+#include "data/cassandra/Concepts.hpp"
+#include "data/cassandra/Handle.hpp"
+#include "data/cassandra/Types.hpp"
+#include "util/log/Logger.hpp"
 
 #include <fmt/compile.h>
 
-namespace Backend::Cassandra {
+#include <functional>
+#include <memory>
+#include <string>
+#include <string_view>
+#include <vector>
+
+namespace data::cassandra {
 
 template <SomeSettingsProvider SettingsProviderType>
 [[nodiscard]] std::string inline qualifiedTableName(SettingsProviderType const& provider, std::string_view name)
@@ -38,17 +41,11 @@ template <SomeSettingsProvider SettingsProviderType>
 }
 
 /**
- * @brief Manages the DB schema and provides access to prepared statements
+ * @brief Manages the DB schema and provides access to prepared statements.
  */
 template <SomeSettingsProvider SettingsProviderType>
-class Schema
-{
-    // Current schema version.
-    // Update this everytime you update the schema.
-    // Migrations will be ran automatically based on this value.
-    static constexpr uint16_t version = 1u;
-
-    clio::Logger log_{"Backend"};
+class Schema {
+    util::Logger log_{"Backend"};
     std::reference_wrapper<SettingsProviderType const> settingsProvider_;
 
 public:
@@ -67,7 +64,8 @@ public:
                AND durable_writes = true
             )",
             settingsProvider_.get().getKeyspace(),
-            settingsProvider_.get().getReplicationFactor());
+            settingsProvider_.get().getReplicationFactor()
+        );
     }();
 
     // =======================
@@ -90,7 +88,8 @@ public:
               AND default_time_to_live = {}
             )",
             qualifiedTableName(settingsProvider_.get(), "objects"),
-            settingsProvider_.get().getTtl()));
+            settingsProvider_.get().getTtl()
+        ));
 
         statements.emplace_back(fmt::format(
             R"(
@@ -105,7 +104,8 @@ public:
              WITH default_time_to_live = {}
             )",
             qualifiedTableName(settingsProvider_.get(), "transactions"),
-            settingsProvider_.get().getTtl()));
+            settingsProvider_.get().getTtl()
+        ));
 
         statements.emplace_back(fmt::format(
             R"(
@@ -118,7 +118,8 @@ public:
              WITH default_time_to_live = {}
             )",
             qualifiedTableName(settingsProvider_.get(), "ledger_transactions"),
-            settingsProvider_.get().getTtl()));
+            settingsProvider_.get().getTtl()
+        ));
 
         statements.emplace_back(fmt::format(
             R"(
@@ -132,7 +133,8 @@ public:
              WITH default_time_to_live = {}
             )",
             qualifiedTableName(settingsProvider_.get(), "successor"),
-            settingsProvider_.get().getTtl()));
+            settingsProvider_.get().getTtl()
+        ));
 
         statements.emplace_back(fmt::format(
             R"(
@@ -145,7 +147,8 @@ public:
              WITH default_time_to_live = {}
             )",
             qualifiedTableName(settingsProvider_.get(), "diff"),
-            settingsProvider_.get().getTtl()));
+            settingsProvider_.get().getTtl()
+        ));
 
         statements.emplace_back(fmt::format(
             R"(
@@ -160,7 +163,8 @@ public:
               AND default_time_to_live = {}
             )",
             qualifiedTableName(settingsProvider_.get(), "account_tx"),
-            settingsProvider_.get().getTtl()));
+            settingsProvider_.get().getTtl()
+        ));
 
         statements.emplace_back(fmt::format(
             R"(
@@ -172,7 +176,8 @@ public:
              WITH default_time_to_live = {}
             )",
             qualifiedTableName(settingsProvider_.get(), "ledgers"),
-            settingsProvider_.get().getTtl()));
+            settingsProvider_.get().getTtl()
+        ));
 
         statements.emplace_back(fmt::format(
             R"(
@@ -184,7 +189,8 @@ public:
              WITH default_time_to_live = {}
             )",
             qualifiedTableName(settingsProvider_.get(), "ledger_hashes"),
-            settingsProvider_.get().getTtl()));
+            settingsProvider_.get().getTtl()
+        ));
 
         statements.emplace_back(fmt::format(
             R"(
@@ -194,7 +200,8 @@ public:
                      sequence bigint
                   )
             )",
-            qualifiedTableName(settingsProvider_.get(), "ledger_range")));
+            qualifiedTableName(settingsProvider_.get(), "ledger_range")
+        ));
 
         statements.emplace_back(fmt::format(
             R"(
@@ -210,7 +217,8 @@ public:
               AND default_time_to_live = {}
             )",
             qualifiedTableName(settingsProvider_.get(), "nf_tokens"),
-            settingsProvider_.get().getTtl()));
+            settingsProvider_.get().getTtl()
+        ));
 
         statements.emplace_back(fmt::format(
             R"(
@@ -225,7 +233,8 @@ public:
               AND default_time_to_live = {}
             )",
             qualifiedTableName(settingsProvider_.get(), "issuer_nf_tokens_v2"),
-            settingsProvider_.get().getTtl()));
+            settingsProvider_.get().getTtl()
+        ));
 
         statements.emplace_back(fmt::format(
             R"(
@@ -240,7 +249,8 @@ public:
               AND default_time_to_live = {}
             )",
             qualifiedTableName(settingsProvider_.get(), "nf_token_uris"),
-            settingsProvider_.get().getTtl()));
+            settingsProvider_.get().getTtl()
+        ));
 
         statements.emplace_back(fmt::format(
             R"(
@@ -255,16 +265,16 @@ public:
               AND default_time_to_live = {}
             )",
             qualifiedTableName(settingsProvider_.get(), "nf_token_transactions"),
-            settingsProvider_.get().getTtl()));
+            settingsProvider_.get().getTtl()
+        ));
 
         return statements;
     }();
 
     /**
-     * @brief Prepared statements holder
+     * @brief Prepared statements holder.
      */
-    class Statements
-    {
+    class Statements {
         std::reference_wrapper<SettingsProviderType const> settingsProvider_;
         std::reference_wrapper<Handle const> handle_;
 
@@ -285,7 +295,8 @@ public:
                        (key, sequence, object)
                 VALUES (?, ?, ?)
                 )",
-                qualifiedTableName(settingsProvider_.get(), "objects")));
+                qualifiedTableName(settingsProvider_.get(), "objects")
+            ));
         }();
 
         PreparedStatement insertTransaction = [this]() {
@@ -295,7 +306,8 @@ public:
                        (hash, ledger_sequence, date, transaction, metadata)
                 VALUES (?, ?, ?, ?, ?)
                 )",
-                qualifiedTableName(settingsProvider_.get(), "transactions")));
+                qualifiedTableName(settingsProvider_.get(), "transactions")
+            ));
         }();
 
         PreparedStatement insertLedgerTransaction = [this]() {
@@ -305,7 +317,8 @@ public:
                        (ledger_sequence, hash)
                 VALUES (?, ?)
                 )",
-                qualifiedTableName(settingsProvider_.get(), "ledger_transactions")));
+                qualifiedTableName(settingsProvider_.get(), "ledger_transactions")
+            ));
         }();
 
         PreparedStatement insertSuccessor = [this]() {
@@ -315,7 +328,8 @@ public:
                        (key, seq, next)
                 VALUES (?, ?, ?)
                 )",
-                qualifiedTableName(settingsProvider_.get(), "successor")));
+                qualifiedTableName(settingsProvider_.get(), "successor")
+            ));
         }();
 
         PreparedStatement insertDiff = [this]() {
@@ -325,7 +339,8 @@ public:
                        (seq, key)
                 VALUES (?, ?)
                 )",
-                qualifiedTableName(settingsProvider_.get(), "diff")));
+                qualifiedTableName(settingsProvider_.get(), "diff")
+            ));
         }();
 
         PreparedStatement insertAccountTx = [this]() {
@@ -335,7 +350,8 @@ public:
                        (account, seq_idx, hash)
                 VALUES (?, ?, ?)
                 )",
-                qualifiedTableName(settingsProvider_.get(), "account_tx")));
+                qualifiedTableName(settingsProvider_.get(), "account_tx")
+            ));
         }();
 
         PreparedStatement insertNFT = [this]() {
@@ -345,7 +361,8 @@ public:
                        (token_id, sequence, owner, is_burned)
                 VALUES (?, ?, ?, ?)
                 )",
-                qualifiedTableName(settingsProvider_.get(), "nf_tokens")));
+                qualifiedTableName(settingsProvider_.get(), "nf_tokens")
+            ));
         }();
 
         PreparedStatement insertIssuerNFT = [this]() {
@@ -355,7 +372,8 @@ public:
                        (issuer, taxon, token_id)
                 VALUES (?, ?, ?)
                 )",
-                qualifiedTableName(settingsProvider_.get(), "issuer_nf_tokens_v2")));
+                qualifiedTableName(settingsProvider_.get(), "issuer_nf_tokens_v2")
+            ));
         }();
 
         PreparedStatement insertNFTURI = [this]() {
@@ -365,7 +383,8 @@ public:
                        (token_id, sequence, uri)
                 VALUES (?, ?, ?)
                 )",
-                qualifiedTableName(settingsProvider_.get(), "nf_token_uris")));
+                qualifiedTableName(settingsProvider_.get(), "nf_token_uris")
+            ));
         }();
 
         PreparedStatement insertNFTTx = [this]() {
@@ -375,7 +394,8 @@ public:
                        (token_id, seq_idx, hash)
                 VALUES (?, ?, ?)
                 )",
-                qualifiedTableName(settingsProvider_.get(), "nf_token_transactions")));
+                qualifiedTableName(settingsProvider_.get(), "nf_token_transactions")
+            ));
         }();
 
         PreparedStatement insertLedgerHeader = [this]() {
@@ -385,7 +405,8 @@ public:
                        (sequence, header)
                 VALUES (?, ?)
                 )",
-                qualifiedTableName(settingsProvider_.get(), "ledgers")));
+                qualifiedTableName(settingsProvider_.get(), "ledgers")
+            ));
         }();
 
         PreparedStatement insertLedgerHash = [this]() {
@@ -395,7 +416,8 @@ public:
                        (hash, sequence)
                 VALUES (?, ?)
                 )",
-                qualifiedTableName(settingsProvider_.get(), "ledger_hashes")));
+                qualifiedTableName(settingsProvider_.get(), "ledger_hashes")
+            ));
         }();
 
         //
@@ -410,7 +432,8 @@ public:
                  WHERE is_latest = ? 
                     IF sequence IN (?, null)
                 )",
-                qualifiedTableName(settingsProvider_.get(), "ledger_range")));
+                qualifiedTableName(settingsProvider_.get(), "ledger_range")
+            ));
         }();
 
         PreparedStatement deleteLedgerRange = [this]() {
@@ -420,7 +443,8 @@ public:
                    SET sequence = ?
                  WHERE is_latest = false
                 )",
-                qualifiedTableName(settingsProvider_.get(), "ledger_range")));
+                qualifiedTableName(settingsProvider_.get(), "ledger_range")
+            ));
         }();
 
         //
@@ -437,7 +461,8 @@ public:
               ORDER BY seq DESC 
                  LIMIT 1
                 )",
-                qualifiedTableName(settingsProvider_.get(), "successor")));
+                qualifiedTableName(settingsProvider_.get(), "successor")
+            ));
         }();
 
         PreparedStatement selectDiff = [this]() {
@@ -447,7 +472,8 @@ public:
                   FROM {}
                  WHERE seq = ?
                 )",
-                qualifiedTableName(settingsProvider_.get(), "diff")));
+                qualifiedTableName(settingsProvider_.get(), "diff")
+            ));
         }();
 
         PreparedStatement selectObject = [this]() {
@@ -460,7 +486,8 @@ public:
               ORDER BY sequence DESC 
                  LIMIT 1
                 )",
-                qualifiedTableName(settingsProvider_.get(), "objects")));
+                qualifiedTableName(settingsProvider_.get(), "objects")
+            ));
         }();
 
         PreparedStatement selectTransaction = [this]() {
@@ -470,7 +497,8 @@ public:
                   FROM {}
                  WHERE hash = ?
                 )",
-                qualifiedTableName(settingsProvider_.get(), "transactions")));
+                qualifiedTableName(settingsProvider_.get(), "transactions")
+            ));
         }();
 
         PreparedStatement selectAllTransactionHashesInLedger = [this]() {
@@ -480,7 +508,8 @@ public:
                   FROM {}               
                  WHERE ledger_sequence = ?               
                 )",
-                qualifiedTableName(settingsProvider_.get(), "ledger_transactions")));
+                qualifiedTableName(settingsProvider_.get(), "ledger_transactions")
+            ));
         }();
 
         PreparedStatement selectLedgerPageKeys = [this]() {
@@ -494,7 +523,8 @@ public:
                  LIMIT ?
                  ALLOW FILTERING
                 )",
-                qualifiedTableName(settingsProvider_.get(), "objects")));
+                qualifiedTableName(settingsProvider_.get(), "objects")
+            ));
         }();
 
         PreparedStatement selectLedgerPage = [this]() {
@@ -508,7 +538,8 @@ public:
                  LIMIT ?
                  ALLOW FILTERING
                 )",
-                qualifiedTableName(settingsProvider_.get(), "objects")));
+                qualifiedTableName(settingsProvider_.get(), "objects")
+            ));
         }();
 
         PreparedStatement getToken = [this]() {
@@ -519,7 +550,8 @@ public:
                  WHERE key = ?               
                  LIMIT 1
                 )",
-                qualifiedTableName(settingsProvider_.get(), "objects")));
+                qualifiedTableName(settingsProvider_.get(), "objects")
+            ));
         }();
 
         PreparedStatement selectAccountTx = [this]() {
@@ -528,10 +560,11 @@ public:
                 SELECT hash, seq_idx 
                   FROM {}               
                  WHERE account = ?
-                   AND seq_idx <= ?
+                   AND seq_idx < ?
                  LIMIT ?
                 )",
-                qualifiedTableName(settingsProvider_.get(), "account_tx")));
+                qualifiedTableName(settingsProvider_.get(), "account_tx")
+            ));
         }();
 
         PreparedStatement selectAccountTxForward = [this]() {
@@ -540,11 +573,12 @@ public:
                 SELECT hash, seq_idx 
                   FROM {}               
                  WHERE account = ?
-                   AND seq_idx >= ?
+                   AND seq_idx > ?
               ORDER BY seq_idx ASC 
                  LIMIT ?
                 )",
-                qualifiedTableName(settingsProvider_.get(), "account_tx")));
+                qualifiedTableName(settingsProvider_.get(), "account_tx")
+            ));
         }();
 
         PreparedStatement selectNFT = [this]() {
@@ -557,7 +591,8 @@ public:
               ORDER BY sequence DESC
                  LIMIT 1
                 )",
-                qualifiedTableName(settingsProvider_.get(), "nf_tokens")));
+                qualifiedTableName(settingsProvider_.get(), "nf_tokens")
+            ));
         }();
 
         PreparedStatement selectNFTURI = [this]() {
@@ -570,7 +605,8 @@ public:
               ORDER BY sequence DESC
                  LIMIT 1
                 )",
-                qualifiedTableName(settingsProvider_.get(), "nf_token_uris")));
+                qualifiedTableName(settingsProvider_.get(), "nf_token_uris")
+            ));
         }();
 
         PreparedStatement selectNFTTx = [this]() {
@@ -583,7 +619,8 @@ public:
               ORDER BY seq_idx DESC
                  LIMIT ?
                 )",
-                qualifiedTableName(settingsProvider_.get(), "nf_token_transactions")));
+                qualifiedTableName(settingsProvider_.get(), "nf_token_transactions")
+            ));
         }();
 
         PreparedStatement selectNFTTxForward = [this]() {
@@ -596,7 +633,37 @@ public:
               ORDER BY seq_idx ASC
                  LIMIT ?
                 )",
-                qualifiedTableName(settingsProvider_.get(), "nf_token_transactions")));
+                qualifiedTableName(settingsProvider_.get(), "nf_token_transactions")
+            ));
+        }();
+
+        PreparedStatement selectNFTIDsByIssuer = [this]() {
+            return handle_.get().prepare(fmt::format(
+                R"(
+                SELECT token_id
+                  FROM {}    
+                 WHERE issuer = ?
+                   AND (taxon, token_id) > ?
+              ORDER BY taxon ASC, token_id ASC
+                 LIMIT ?
+                )",
+                qualifiedTableName(settingsProvider_.get(), "issuer_nf_tokens_v2")
+            ));
+        }();
+
+        PreparedStatement selectNFTIDsByIssuerTaxon = [this]() {
+            return handle_.get().prepare(fmt::format(
+                R"(
+                SELECT token_id
+                  FROM {}    
+                 WHERE issuer = ?
+                   AND taxon = ?
+                   AND token_id > ?
+              ORDER BY taxon ASC, token_id ASC
+                 LIMIT ?
+                )",
+                qualifiedTableName(settingsProvider_.get(), "issuer_nf_tokens_v2")
+            ));
         }();
 
         PreparedStatement selectLedgerByHash = [this]() {
@@ -607,7 +674,8 @@ public:
                  WHERE hash = ?     
                  LIMIT 1
                 )",
-                qualifiedTableName(settingsProvider_.get(), "ledger_hashes")));
+                qualifiedTableName(settingsProvider_.get(), "ledger_hashes")
+            ));
         }();
 
         PreparedStatement selectLedgerBySeq = [this]() {
@@ -617,7 +685,8 @@ public:
                   FROM {}
                  WHERE sequence = ?
                 )",
-                qualifiedTableName(settingsProvider_.get(), "ledgers")));
+                qualifiedTableName(settingsProvider_.get(), "ledgers")
+            ));
         }();
 
         PreparedStatement selectLatestLedger = [this]() {
@@ -627,7 +696,8 @@ public:
                   FROM {}    
                  WHERE is_latest = true               
                 )",
-                qualifiedTableName(settingsProvider_.get(), "ledger_range")));
+                qualifiedTableName(settingsProvider_.get(), "ledger_range")
+            ));
         }();
 
         PreparedStatement selectLedgerRange = [this]() {
@@ -636,23 +706,24 @@ public:
                 SELECT sequence
                   FROM {}
                 )",
-                qualifiedTableName(settingsProvider_.get(), "ledger_range")));
+                qualifiedTableName(settingsProvider_.get(), "ledger_range")
+            ));
         }();
     };
 
     /**
-     * @brief Recreates the prepared statements
+     * @brief Recreates the prepared statements.
      */
     void
     prepareStatements(Handle const& handle)
     {
-        log_.info() << "Preparing cassandra statements";
+        LOG(log_.info()) << "Preparing cassandra statements";
         statements_ = std::make_unique<Statements>(settingsProvider_, handle);
-        log_.info() << "Finished preparing statements";
+        LOG(log_.info()) << "Finished preparing statements";
     }
 
     /**
-     * @brief Provides access to statements
+     * @brief Provides access to statements.
      */
     std::unique_ptr<Statements> const&
     operator->() const
@@ -664,4 +735,4 @@ private:
     std::unique_ptr<Statements> statements_{nullptr};
 };
 
-}  // namespace Backend::Cassandra
+}  // namespace data::cassandra

src/data/cassandra/SettingsProvider.cpp

@@ -17,28 +17,40 @@
 */
 //==============================================================================
 
-#include <backend/cassandra/SettingsProvider.h>
-#include <backend/cassandra/impl/Cluster.h>
-#include <backend/cassandra/impl/Statement.h>
-#include <config/Config.h>
+#include "data/cassandra/SettingsProvider.hpp"
 
-#include <boost/json.hpp>
+#include "data/cassandra/Types.hpp"
+#include "data/cassandra/impl/Cluster.hpp"
+#include "util/Constants.hpp"
+#include "util/config/Config.hpp"
 
+#include <boost/json/conversion.hpp>
+#include <boost/json/value.hpp>
+
+#include <cerrno>
+#include <chrono>
+#include <cstddef>
+#include <cstdint>
+#include <filesystem>
+#include <fstream>
+#include <ios>
+#include <iterator>
+#include <optional>
+#include <stdexcept>
 #include <string>
-#include <thread>
+#include <system_error>
 
-namespace Backend::Cassandra {
+namespace data::cassandra {
 
 namespace detail {
 inline Settings::ContactPoints
 tag_invoke(boost::json::value_to_tag<Settings::ContactPoints>, boost::json::value const& value)
 {
-    if (not value.is_object())
-        throw std::runtime_error(
-            "Feed entire Cassandra section to parse "
-            "Settings::ContactPoints instead");
+    if (not value.is_object()) {
+        throw std::runtime_error("Feed entire Cassandra section to parse Settings::ContactPoints instead");
+    }
 
-    clio::Config obj{value};
+    util::Config const obj{value};
     Settings::ContactPoints out;
 
     out.contactPoints = obj.valueOrThrow<std::string>("contact_points", "`contact_points` must be a string");
@@ -56,7 +68,7 @@ tag_invoke(boost::json::value_to_tag<Settings::SecureConnectionBundle>, boost::j
 }
 }  // namespace detail
 
-SettingsProvider::SettingsProvider(clio::Config const& cfg, uint16_t ttl)
+SettingsProvider::SettingsProvider(util::Config const& cfg, uint16_t ttl)
     : config_{cfg}
     , keyspace_{cfg.valueOr<std::string>("keyspace", "clio")}
     , tablePrefix_{cfg.maybeValue<std::string>("table_prefix")}
@@ -75,18 +87,15 @@ SettingsProvider::getSettings() const
 std::optional<std::string>
 SettingsProvider::parseOptionalCertificate() const
 {
-    if (auto const certPath = config_.maybeValue<std::string>("certfile"); certPath)
-    {
+    if (auto const certPath = config_.maybeValue<std::string>("certfile"); certPath) {
         auto const path = std::filesystem::path(*certPath);
         std::ifstream fileStream(path.string(), std::ios::in);
-        if (!fileStream)
-        {
+        if (!fileStream) {
             throw std::system_error(errno, std::generic_category(), "Opening certificate " + path.string());
         }
 
         std::string contents(std::istreambuf_iterator<char>{fileStream}, std::istreambuf_iterator<char>{});
-        if (fileStream.bad())
-        {
+        if (fileStream.bad()) {
             throw std::system_error(errno, std::generic_category(), "Reading certificate " + path.string());
         }
 
@@ -100,12 +109,9 @@ Settings
 SettingsProvider::parseSettings() const
 {
     auto settings = Settings::defaultSettings();
-    if (auto const bundle = config_.maybeValue<Settings::SecureConnectionBundle>("secure_connect_bundle"); bundle)
-    {
+    if (auto const bundle = config_.maybeValue<Settings::SecureConnectionBundle>("secure_connect_bundle"); bundle) {
         settings.connectionInfo = *bundle;
-    }
-    else
-    {
+    } else {
         settings.connectionInfo =
             config_.valueOrThrow<Settings::ContactPoints>("Missing contact_points in Cassandra config");
     }
@@ -115,6 +121,19 @@ SettingsProvider::parseSettings() const
         config_.valueOr<uint32_t>("max_write_requests_outstanding", settings.maxWriteRequestsOutstanding);
     settings.maxReadRequestsOutstanding =
         config_.valueOr<uint32_t>("max_read_requests_outstanding", settings.maxReadRequestsOutstanding);
+    settings.coreConnectionsPerHost =
+        config_.valueOr<uint32_t>("core_connections_per_host", settings.coreConnectionsPerHost);
+    settings.queueSizeIO = config_.maybeValue<uint32_t>("queue_size_io");
+    settings.writeBatchSize = config_.valueOr<std::size_t>("write_batch_size", settings.writeBatchSize);
+
+    auto const connectTimeoutSecond = config_.maybeValue<uint32_t>("connect_timeout");
+    if (connectTimeoutSecond)
+        settings.connectionTimeout = std::chrono::milliseconds{*connectTimeoutSecond * util::MILLISECONDS_PER_SECOND};
+
+    auto const requestTimeoutSecond = config_.maybeValue<uint32_t>("request_timeout");
+    if (requestTimeoutSecond)
+        settings.requestTimeout = std::chrono::milliseconds{*requestTimeoutSecond * util::MILLISECONDS_PER_SECOND};
+
     settings.certificate = parseOptionalCertificate();
     settings.username = config_.maybeValue<std::string>("username");
     settings.password = config_.maybeValue<std::string>("password");
@@ -122,4 +141,4 @@ SettingsProvider::parseSettings() const
     return settings;
 }
 
-}  // namespace Backend::Cassandra
+}  // namespace data::cassandra

src/data/cassandra/SettingsProvider.hpp

@@ -19,20 +19,22 @@
 
 #pragma once
 
-#include <backend/cassandra/Handle.h>
-#include <backend/cassandra/Types.h>
-#include <config/Config.h>
-#include <log/Logger.h>
-#include <util/Expected.h>
+#include "data/cassandra/Handle.hpp"
+#include "data/cassandra/Types.hpp"
+#include "util/config/Config.hpp"
+#include "util/log/Logger.hpp"
 
-namespace Backend::Cassandra {
+#include <cstdint>
+#include <optional>
+#include <string>
+
+namespace data::cassandra {
 
 /**
- * @brief Provides settings for @ref CassandraBackend
+ * @brief Provides settings for @ref BasicCassandraBackend.
  */
-class SettingsProvider
-{
-    clio::Config config_;
+class SettingsProvider {
+    util::Config config_;
 
     std::string keyspace_;
     std::optional<std::string> tablePrefix_;
@@ -41,34 +43,50 @@ class SettingsProvider
     Settings settings_;
 
 public:
-    explicit SettingsProvider(clio::Config const& cfg, uint16_t ttl = 0);
+    /**
+     * @brief Create a settings provider from the specified config.
+     *
+     * @param cfg The config of Clio to use
+     * @param ttl Time to live setting
+     */
+    explicit SettingsProvider(util::Config const& cfg, uint16_t ttl = 0);
 
-    /*! Get the cluster settings */
+    /**
+     * @return The cluster settings
+     */
     [[nodiscard]] Settings
     getSettings() const;
 
-    /*! Get the specified keyspace */
+    /**
+     * @return The specified keyspace
+     */
     [[nodiscard]] inline std::string
     getKeyspace() const
     {
         return keyspace_;
     }
 
-    /*! Get an optional table prefix to use in all queries */
+    /**
+     * @return The optional table prefix to use in all queries
+     */
     [[nodiscard]] inline std::optional<std::string>
     getTablePrefix() const
     {
         return tablePrefix_;
     }
 
-    /*! Get the replication factor */
+    /**
+     * @return The replication factor
+     */
     [[nodiscard]] inline uint16_t
     getReplicationFactor() const
     {
         return replicationFactor_;
     }
 
-    /*! Get the default time to live to use in all `create` queries */
+    /**
+     * @return The default time to live to use in all `create` queries
+     */
     [[nodiscard]] inline uint16_t
     getTtl() const
     {
@@ -83,4 +101,4 @@ private:
     parseSettings() const;
 };
 
-}  // namespace Backend::Cassandra
+}  // namespace data::cassandra

src/data/cassandra/Types.hpp

@@ -19,11 +19,11 @@
 
 #pragma once
 
-#include <util/Expected.h>
+#include "util/Expected.hpp"
 
-#include <string>
+#include <cstdint>
 
-namespace Backend::Cassandra {
+namespace data::cassandra {
 
 namespace detail {
 struct Settings;
@@ -52,8 +52,7 @@ using Batch = detail::Batch;
  * because clio uses bigint (int64) everywhere except for when one need
  * to specify LIMIT, which needs an int32 :-/
  */
-struct Limit
-{
+struct Limit {
     int32_t limit;
 };
 
@@ -64,4 +63,4 @@ using MaybeError = util::Expected<void, CassandraError>;
 using ResultOrError = util::Expected<Result, CassandraError>;
 using Error = util::Unexpected<CassandraError>;
 
-}  // namespace Backend::Cassandra
+}  // namespace data::cassandra

src/data/cassandra/impl/AsyncExecutor.hpp

@@ -19,19 +19,22 @@
 
 #pragma once
 
-#include <backend/cassandra/Concepts.h>
-#include <backend/cassandra/Handle.h>
-#include <backend/cassandra/Types.h>
-#include <backend/cassandra/impl/RetryPolicy.h>
-#include <log/Logger.h>
-#include <util/Expected.h>
+#include "data/cassandra/Concepts.hpp"
+#include "data/cassandra/Handle.hpp"
+#include "data/cassandra/Types.hpp"
+#include "data/cassandra/impl/RetryPolicy.hpp"
+#include "util/log/Logger.hpp"
 
 #include <boost/asio.hpp>
+#include <boost/asio/io_context.hpp>
 
 #include <functional>
 #include <memory>
+#include <mutex>
+#include <optional>
+#include <utility>
 
-namespace Backend::Cassandra::detail {
+namespace data::cassandra::detail {
 
 /**
  * @brief A query executor with a changable retry policy
@@ -48,16 +51,17 @@ template <
     typename StatementType,
     typename HandleType = Handle,
     SomeRetryPolicy RetryPolicyType = ExponentialBackoffRetryPolicy>
-class AsyncExecutor : public std::enable_shared_from_this<AsyncExecutor<StatementType, HandleType, RetryPolicyType>>
-{
+class AsyncExecutor : public std::enable_shared_from_this<AsyncExecutor<StatementType, HandleType, RetryPolicyType>> {
     using FutureWithCallbackType = typename HandleType::FutureWithCallbackType;
     using CallbackType = std::function<void(typename HandleType::ResultOrErrorType)>;
+    using RetryCallbackType = std::function<void()>;
 
-    clio::Logger log_{"Backend"};
+    util::Logger log_{"Backend"};
 
     StatementType data_;
     RetryPolicyType retryPolicy_;
     CallbackType onComplete_;
+    RetryCallbackType onRetry_;
 
     // does not exist during initial construction, hence optional
     std::optional<FutureWithCallbackType> future_;
@@ -68,24 +72,37 @@ public:
      * @brief Create a new instance of the AsyncExecutor and execute it.
      */
     static void
-    run(boost::asio::io_context& ioc, HandleType const& handle, StatementType&& data, CallbackType&& onComplete)
+    run(boost::asio::io_context& ioc,
+        HandleType const& handle,
+        StatementType&& data,
+        CallbackType&& onComplete,
+        RetryCallbackType&& onRetry)
     {
         // this is a helper that allows us to use std::make_shared below
-        struct EnableMakeShared : public AsyncExecutor<StatementType, HandleType, RetryPolicyType>
-        {
-            EnableMakeShared(boost::asio::io_context& ioc, StatementType&& data, CallbackType&& onComplete)
-                : AsyncExecutor(ioc, std::move(data), std::move(onComplete))
+        struct EnableMakeShared : public AsyncExecutor<StatementType, HandleType, RetryPolicyType> {
+            EnableMakeShared(
+                boost::asio::io_context& ioc,
+                StatementType&& data,
+                CallbackType&& onComplete,
+                RetryCallbackType&& onRetry
+            )
+                : AsyncExecutor(ioc, std::move(data), std::move(onComplete), std::move(onRetry))
             {
             }
         };
 
-        auto ptr = std::make_shared<EnableMakeShared>(ioc, std::move(data), std::move(onComplete));
+        auto ptr = std::make_shared<EnableMakeShared>(ioc, std::move(data), std::move(onComplete), std::move(onRetry));
         ptr->execute(handle);
     }
 
 private:
-    AsyncExecutor(boost::asio::io_context& ioc, StatementType&& data, CallbackType&& onComplete)
-        : data_{std::move(data)}, retryPolicy_{ioc}, onComplete_{std::move(onComplete)}
+    AsyncExecutor(
+        boost::asio::io_context& ioc,
+        StatementType&& data,
+        CallbackType&& onComplete,
+        RetryCallbackType&& onRetry
+    )
+        : data_{std::move(data)}, retryPolicy_{ioc}, onComplete_{std::move(onComplete)}, onRetry_{std::move(onRetry)}
     {
     }
 
@@ -96,24 +113,23 @@ private:
 
         // lifetime is extended by capturing self ptr
         auto handler = [this, &handle, self](auto&& res) mutable {
-            if (res)
-            {
-                onComplete_(std::move(res));
-            }
-            else
-            {
-                if (retryPolicy_.shouldRetry(res.error()))
+            if (res) {
+                onComplete_(std::forward<decltype(res)>(res));
+            } else {
+                if (retryPolicy_.shouldRetry(res.error())) {
+                    onRetry_();
                     retryPolicy_.retry([self, &handle]() { self->execute(handle); });
-                else
-                    onComplete_(std::move(res));  // report error
+                } else {
+                    onComplete_(std::forward<decltype(res)>(res));  // report error
+                }
             }
 
             self = nullptr;  // explicitly decrement refcount
         };
 
-        std::scoped_lock lck{mtx_};
+        std::scoped_lock const lck{mtx_};
         future_.emplace(handle.asyncExecute(data_, std::move(handler)));
     }
 };
 
-}  // namespace Backend::Cassandra::detail
+}  // namespace data::cassandra::detail

src/data/cassandra/impl/Batch.cpp

@@ -17,40 +17,44 @@
 */
 //==============================================================================
 
-#include <backend/cassandra/Error.h>
-#include <backend/cassandra/impl/Batch.h>
-#include <backend/cassandra/impl/Statement.h>
-#include <util/Expected.h>
+#include "data/cassandra/impl/Batch.hpp"
 
-#include <exception>
+#include "data/cassandra/Error.hpp"
+#include "data/cassandra/Types.hpp"
+#include "data/cassandra/impl/ManagedObject.hpp"
+#include "data/cassandra/impl/Statement.hpp"
+#include "util/Expected.hpp"
+
+#include <cassandra.h>
+
+#include <stdexcept>
 #include <vector>
 
 namespace {
-static constexpr auto batchDeleter = [](CassBatch* ptr) { cass_batch_free(ptr); };
-};
+constexpr auto batchDeleter = [](CassBatch* ptr) { cass_batch_free(ptr); };
+}  // namespace
 
-namespace Backend::Cassandra::detail {
+namespace data::cassandra::detail {
 
-// todo: use an appropritae value instead of CASS_BATCH_TYPE_LOGGED for
-// different use cases
+// TODO: Use an appropriate value instead of CASS_BATCH_TYPE_LOGGED for different use cases
 Batch::Batch(std::vector<Statement> const& statements)
     : ManagedObject{cass_batch_new(CASS_BATCH_TYPE_LOGGED), batchDeleter}
 {
     cass_batch_set_is_idempotent(*this, cass_true);
 
-    for (auto const& statement : statements)
+    for (auto const& statement : statements) {
         if (auto const res = add(statement); not res)
             throw std::runtime_error("Failed to add statement to batch: " + res.error());
+    }
 }
 
 MaybeError
 Batch::add(Statement const& statement)
 {
-    if (auto const rc = cass_batch_add_statement(*this, statement); rc != CASS_OK)
-    {
+    if (auto const rc = cass_batch_add_statement(*this, statement); rc != CASS_OK) {
         return Error{CassandraError{cass_error_desc(rc), rc}};
     }
     return {};
 }
 
-}  // namespace Backend::Cassandra::detail
+}  // namespace data::cassandra::detail

src/data/cassandra/impl/Batch.hpp

@@ -19,19 +19,20 @@
 
 #pragma once
 
-#include <backend/cassandra/Types.h>
-#include <backend/cassandra/impl/ManagedObject.h>
+#include "data/cassandra/Types.hpp"
+#include "data/cassandra/impl/ManagedObject.hpp"
 
 #include <cassandra.h>
 
-namespace Backend::Cassandra::detail {
+#include <vector>
 
-struct Batch : public ManagedObject<CassBatch>
-{
+namespace data::cassandra::detail {
+
+struct Batch : public ManagedObject<CassBatch> {
     Batch(std::vector<Statement> const& statements);
 
     MaybeError
     add(Statement const& statement);
 };
 
-}  // namespace Backend::Cassandra::detail
+}  // namespace data::cassandra::detail

src/data/cassandra/impl/Cluster.cpp

@@ -17,20 +17,24 @@
 */
 //==============================================================================
 
-#include <backend/cassandra/impl/Cluster.h>
-#include <backend/cassandra/impl/SslContext.h>
-#include <backend/cassandra/impl/Statement.h>
-#include <util/Expected.h>
+#include "data/cassandra/impl/Cluster.hpp"
 
-#include <exception>
-#include <vector>
+#include "data/cassandra/impl/ManagedObject.hpp"
+#include "data/cassandra/impl/SslContext.hpp"
+#include "util/log/Logger.hpp"
+
+#include <cassandra.h>
+#include <fmt/core.h>
+
+#include <stdexcept>
+#include <string>
+#include <variant>
 
 namespace {
-static constexpr auto clusterDeleter = [](CassCluster* ptr) { cass_cluster_free(ptr); };
+constexpr auto clusterDeleter = [](CassCluster* ptr) { cass_cluster_free(ptr); };
 
 template <class... Ts>
-struct overloadSet : Ts...
-{
+struct overloadSet : Ts... {
     using Ts::operator()...;
 };
 
@@ -39,53 +43,47 @@ template <class... Ts>
 overloadSet(Ts...) -> overloadSet<Ts...>;
 };  // namespace
 
-namespace Backend::Cassandra::detail {
+namespace data::cassandra::detail {
 
 Cluster::Cluster(Settings const& settings) : ManagedObject{cass_cluster_new(), clusterDeleter}
 {
     using std::to_string;
 
     cass_cluster_set_token_aware_routing(*this, cass_true);
-    if (auto const rc = cass_cluster_set_protocol_version(*this, CASS_PROTOCOL_VERSION_V4); rc != CASS_OK)
-    {
-        throw std::runtime_error(std::string{"Error setting cassandra protocol version to v4: "} + cass_error_desc(rc));
+    if (auto const rc = cass_cluster_set_protocol_version(*this, CASS_PROTOCOL_VERSION_V4); rc != CASS_OK) {
+        throw std::runtime_error(fmt::format("Error setting cassandra protocol version to v4: {}", cass_error_desc(rc))
+        );
     }
 
-    if (auto const rc = cass_cluster_set_num_threads_io(*this, settings.threads); rc != CASS_OK)
-    {
+    if (auto const rc = cass_cluster_set_num_threads_io(*this, settings.threads); rc != CASS_OK) {
         throw std::runtime_error(
-            std::string{"Error setting cassandra io threads to "} + to_string(settings.threads) + ": " +
-            cass_error_desc(rc));
+            fmt::format("Error setting cassandra io threads to {}: {}", settings.threads, cass_error_desc(rc))
+        );
     }
 
     cass_log_set_level(settings.enableLog ? CASS_LOG_TRACE : CASS_LOG_DISABLED);
     cass_cluster_set_connect_timeout(*this, settings.connectionTimeout.count());
     cass_cluster_set_request_timeout(*this, settings.requestTimeout.count());
 
-    // TODO: other options to experiment with and consider later:
-    // cass_cluster_set_max_concurrent_requests_threshold(*this, 10000);
-    // cass_cluster_set_queue_size_event(*this, 100000);
-    // cass_cluster_set_queue_size_io(*this, 100000);
-    // cass_cluster_set_write_bytes_high_water_mark(*this, 16 * 1024 * 1024);  // 16mb
-    // cass_cluster_set_write_bytes_low_water_mark(*this, 8 * 1024 * 1024);  // half of allowance
-    // cass_cluster_set_pending_requests_high_water_mark(*this, 5000);
-    // cass_cluster_set_pending_requests_low_water_mark(*this, 2500);  // half
-    // cass_cluster_set_max_requests_per_flush(*this, 1000);
-    // cass_cluster_set_max_concurrent_creation(*this, 8);
-    // cass_cluster_set_max_connections_per_host(*this, 6);
-    // cass_cluster_set_core_connections_per_host(*this, 4);
-    // cass_cluster_set_constant_speculative_execution_policy(*this, 1000, 1024);
+    if (auto const rc = cass_cluster_set_core_connections_per_host(*this, settings.coreConnectionsPerHost);
+        rc != CASS_OK) {
+        throw std::runtime_error(fmt::format("Could not set core connections per host: {}", cass_error_desc(rc)));
+    }
 
-    if (auto const rc = cass_cluster_set_queue_size_io(
-            *this, settings.maxWriteRequestsOutstanding + settings.maxReadRequestsOutstanding);
-        rc != CASS_OK)
-    {
-        throw std::runtime_error(std::string{"Could not set queue size for IO per host: "} + cass_error_desc(rc));
+    auto const queueSize =
+        settings.queueSizeIO.value_or(settings.maxWriteRequestsOutstanding + settings.maxReadRequestsOutstanding);
+    if (auto const rc = cass_cluster_set_queue_size_io(*this, queueSize); rc != CASS_OK) {
+        throw std::runtime_error(fmt::format("Could not set queue size for IO per host: {}", cass_error_desc(rc)));
     }
 
     setupConnection(settings);
     setupCertificate(settings);
     setupCredentials(settings);
+
+    LOG(log_.info()) << "Threads: " << settings.threads;
+    LOG(log_.info()) << "Core connections per host: " << settings.coreConnectionsPerHost;
+    LOG(log_.info()) << "IO queue size: " << queueSize;
+    LOG(log_.info()) << "Batched writes auto-chunk size: " << settings.writeBatchSize;
 }
 
 void
@@ -94,27 +92,31 @@ Cluster::setupConnection(Settings const& settings)
     std::visit(
         overloadSet{
             [this](Settings::ContactPoints const& points) { setupContactPoints(points); },
-            [this](Settings::SecureConnectionBundle const& bundle) { setupSecureBundle(bundle); }},
-        settings.connectionInfo);
+            [this](Settings::SecureConnectionBundle const& bundle) { setupSecureBundle(bundle); }
+        },
+        settings.connectionInfo
+    );
 }
 
 void
 Cluster::setupContactPoints(Settings::ContactPoints const& points)
 {
     using std::to_string;
-    auto throwErrorIfNeeded = [](CassError rc, std::string const label, std::string const value) {
-        if (rc != CASS_OK)
-            throw std::runtime_error("Cassandra: Error setting " + label + " [" + value + "]: " + cass_error_desc(rc));
+    auto throwErrorIfNeeded = [](CassError rc, std::string const& label, std::string const& value) {
+        if (rc != CASS_OK) {
+            throw std::runtime_error(
+                fmt::format("Cassandra: Error setting {} [{}]: {}", label, value, cass_error_desc(rc))
+            );
+        }
     };
 
     {
-        log_.debug() << "Attempt connection using contact points: " << points.contactPoints;
+        LOG(log_.debug()) << "Attempt connection using contact points: " << points.contactPoints;
         auto const rc = cass_cluster_set_contact_points(*this, points.contactPoints.data());
         throwErrorIfNeeded(rc, "contact_points", points.contactPoints);
     }
 
-    if (points.port)
-    {
+    if (points.port) {
         auto const rc = cass_cluster_set_port(*this, points.port.value());
         throwErrorIfNeeded(rc, "port", to_string(points.port.value()));
     }
@@ -123,10 +125,9 @@ Cluster::setupContactPoints(Settings::ContactPoints const& points)
 void
 Cluster::setupSecureBundle(Settings::SecureConnectionBundle const& bundle)
 {
-    log_.debug() << "Attempt connection using secure bundle";
-    if (auto const rc = cass_cluster_set_cloud_secure_connection_bundle(*this, bundle.bundle.data()); rc != CASS_OK)
-    {
-        throw std::runtime_error("Failed to connect using secure connection bundle" + bundle.bundle);
+    LOG(log_.debug()) << "Attempt connection using secure bundle";
+    if (auto const rc = cass_cluster_set_cloud_secure_connection_bundle(*this, bundle.bundle.data()); rc != CASS_OK) {
+        throw std::runtime_error("Failed to connect using secure connection bundle " + bundle.bundle);
     }
 }
 
@@ -136,8 +137,8 @@ Cluster::setupCertificate(Settings const& settings)
     if (not settings.certificate)
         return;
 
-    log_.debug() << "Configure SSL context";
-    SslContext context = SslContext(*settings.certificate);
+    LOG(log_.debug()) << "Configure SSL context";
+    SslContext const context = SslContext(*settings.certificate);
     cass_cluster_set_ssl(*this, context);
 }
 
@@ -147,8 +148,8 @@ Cluster::setupCredentials(Settings const& settings)
     if (not settings.username || not settings.password)
         return;
 
-    log_.debug() << "Set credentials; username: " << settings.username.value();
+    LOG(log_.debug()) << "Set credentials; username: " << settings.username.value();
     cass_cluster_set_credentials(*this, settings.username.value().c_str(), settings.password.value().c_str());
 }
 
-}  // namespace Backend::Cassandra::detail
+}  // namespace data::cassandra::detail

src/data/cassandra/impl/Cluster.hpp

@@ -0,0 +1,145 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of clio: https://github.com/XRPLF/clio
+    Copyright (c) 2023, the clio developers.
+
+    Permission to use, copy, modify, and distribute this software for any
+    purpose with or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL,  DIRECT,  INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+
+#pragma once
+
+#include "data/cassandra/impl/ManagedObject.hpp"
+#include "util/log/Logger.hpp"
+
+#include <cassandra.h>
+
+#include <chrono>
+#include <optional>
+#include <string>
+#include <string_view>
+#include <thread>
+#include <variant>
+
+namespace data::cassandra::detail {
+
+// TODO: move Settings to public interface, not detail
+
+/**
+ * @brief Bundles all cassandra settings in one place.
+ */
+struct Settings {
+    static constexpr std::size_t DEFAULT_CONNECTION_TIMEOUT = 10000;
+    static constexpr uint32_t DEFAULT_MAX_WRITE_REQUESTS_OUTSTANDING = 10'000;
+    static constexpr uint32_t DEFAULT_MAX_READ_REQUESTS_OUTSTANDING = 100'000;
+    static constexpr std::size_t DEFAULT_BATCH_SIZE = 20;
+
+    /**
+     * @brief Represents the configuration of contact points for cassandra.
+     */
+    struct ContactPoints {
+        std::string contactPoints = "127.0.0.1";  // defaults to localhost
+        std::optional<uint16_t> port = {};
+    };
+
+    /**
+     * @brief Represents the configuration of a secure connection bundle.
+     */
+    struct SecureConnectionBundle {
+        std::string bundle;  // no meaningful default
+    };
+
+    /** @brief Enables or disables cassandra driver logger */
+    bool enableLog = false;
+
+    /** @brief Connect timeout specified in milliseconds */
+    std::chrono::milliseconds connectionTimeout = std::chrono::milliseconds{DEFAULT_CONNECTION_TIMEOUT};
+
+    /** @brief Request timeout specified in milliseconds */
+    std::chrono::milliseconds requestTimeout = std::chrono::milliseconds{0};  // no timeout at all
+
+    /** @brief Connection information; either ContactPoints or SecureConnectionBundle */
+    std::variant<ContactPoints, SecureConnectionBundle> connectionInfo = ContactPoints{};
+
+    /** @brief The number of threads for the driver to pool */
+    uint32_t threads = std::thread::hardware_concurrency();
+
+    /** @brief The maximum number of outstanding write requests at any given moment */
+    uint32_t maxWriteRequestsOutstanding = DEFAULT_MAX_WRITE_REQUESTS_OUTSTANDING;
+
+    /** @brief The maximum number of outstanding read requests at any given moment */
+    uint32_t maxReadRequestsOutstanding = DEFAULT_MAX_READ_REQUESTS_OUTSTANDING;
+
+    /** @brief The number of connection per host to always have active */
+    uint32_t coreConnectionsPerHost = 1u;
+
+    /** @brief Size of batches when writing */
+    std::size_t writeBatchSize = DEFAULT_BATCH_SIZE;
+
+    /** @brief Size of the IO queue */
+    std::optional<uint32_t> queueSizeIO{};
+
+    /** @brief SSL certificate */
+    std::optional<std::string> certificate{};  // ssl context
+
+    /** @brief Username/login */
+    std::optional<std::string> username{};
+
+    /** @brief Password to match the `username` */
+    std::optional<std::string> password{};
+
+    /**
+     * @brief Creates a new Settings object as a copy of the current one with overridden contact points.
+     */
+    Settings
+    withContactPoints(std::string_view contactPoints)
+    {
+        auto tmp = *this;
+        tmp.connectionInfo = ContactPoints{std::string{contactPoints}};
+        return tmp;
+    }
+
+    /**
+     * @brief Returns the default settings.
+     */
+    static Settings
+    defaultSettings()
+    {
+        return Settings();
+    }
+};
+
+class Cluster : public ManagedObject<CassCluster> {
+    util::Logger log_{"Backend"};
+
+public:
+    Cluster(Settings const& settings);
+
+private:
+    void
+    setupConnection(Settings const& settings);
+
+    void
+    setupContactPoints(Settings::ContactPoints const& points);
+
+    void
+    setupSecureBundle(Settings::SecureConnectionBundle const& bundle);
+
+    void
+    setupCertificate(Settings const& settings);
+
+    void
+    setupCredentials(Settings const& settings);
+};
+
+}  // namespace data::cassandra::detail

src/data/cassandra/impl/Collection.hpp

@@ -0,0 +1,90 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of clio: https://github.com/XRPLF/clio
+    Copyright (c) 2023, the clio developers.
+
+    Permission to use, copy, modify, and distribute this software for any
+    purpose with or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL,  DIRECT,  INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+
+#pragma once
+
+#include "data/cassandra/impl/ManagedObject.hpp"
+
+#include <cassandra.h>
+#include <ripple/basics/base_uint.h>
+
+#include <cstdint>
+#include <stdexcept>
+#include <string>
+#include <string_view>
+#include <vector>
+
+namespace data::cassandra::detail {
+
+class Collection : public ManagedObject<CassCollection> {
+    static constexpr auto deleter = [](CassCollection* ptr) { cass_collection_free(ptr); };
+
+    static void
+    throwErrorIfNeeded(CassError const rc, std::string_view const label)
+    {
+        if (rc == CASS_OK)
+            return;
+        auto const tag = '[' + std::string{label} + ']';
+        throw std::logic_error(tag + ": " + cass_error_desc(rc));
+    }
+
+public:
+    /* implicit */ Collection(CassCollection* ptr);
+
+    template <typename Type>
+    explicit Collection(std::vector<Type> const& value)
+        : ManagedObject{cass_collection_new(CASS_COLLECTION_TYPE_LIST, value.size()), deleter}
+    {
+        bind(value);
+    }
+
+    template <typename Type>
+    void
+    bind(std::vector<Type> const& values) const
+    {
+        for (auto const& value : values)
+            append(value);
+    }
+
+    void
+    append(bool const value) const
+    {
+        auto const rc = cass_collection_append_bool(*this, value ? cass_true : cass_false);
+        throwErrorIfNeeded(rc, "Bind bool");
+    }
+
+    void
+    append(int64_t const value) const
+    {
+        auto const rc = cass_collection_append_int64(*this, value);
+        throwErrorIfNeeded(rc, "Bind int64");
+    }
+
+    void
+    append(ripple::uint256 const& value) const
+    {
+        auto const rc = cass_collection_append_bytes(
+            *this,
+            static_cast<cass_byte_t const*>(static_cast<unsigned char const*>(value.data())),
+            ripple::uint256::size()
+        );
+        throwErrorIfNeeded(rc, "Bind ripple::uint256");
+    }
+};
+}  // namespace data::cassandra::detail

src/data/cassandra/impl/ExecutionStrategy.hpp

@@ -0,0 +1,538 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of clio: https://github.com/XRPLF/clio
+    Copyright (c) 2023, the clio developers.
+
+    Permission to use, copy, modify, and distribute this software for any
+    purpose with or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL,  DIRECT,  INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+
+#pragma once
+
+#include "data/BackendCounters.hpp"
+#include "data/BackendInterface.hpp"
+#include "data/cassandra/Handle.hpp"
+#include "data/cassandra/Types.hpp"
+#include "data/cassandra/impl/AsyncExecutor.hpp"
+#include "util/Assert.hpp"
+#include "util/Batching.hpp"
+#include "util/log/Logger.hpp"
+
+#include <boost/asio.hpp>
+#include <boost/asio/associated_executor.hpp>
+#include <boost/asio/io_context.hpp>
+#include <boost/asio/io_service.hpp>
+#include <boost/asio/spawn.hpp>
+#include <boost/json/object.hpp>
+
+#include <atomic>
+#include <chrono>
+#include <condition_variable>
+#include <cstddef>
+#include <cstdint>
+#include <functional>
+#include <memory>
+#include <mutex>
+#include <optional>
+#include <stdexcept>
+#include <thread>
+#include <type_traits>
+#include <vector>
+
+namespace data::cassandra::detail {
+
+// TODO: this could probably be also moved out of detail and into the main cassandra namespace.
+
+/**
+ * @brief Implements async and sync querying against the cassandra DB with support for throttling.
+ *
+ * Note: A lot of the code that uses yield is repeated below.
+ * This is ok for now because we are hopefully going to be getting rid of it entirely later on.
+ */
+template <typename HandleType = Handle, SomeBackendCounters BackendCountersType = BackendCounters>
+class DefaultExecutionStrategy {
+    util::Logger log_{"Backend"};
+
+    std::uint32_t maxWriteRequestsOutstanding_;
+    std::atomic_uint32_t numWriteRequestsOutstanding_ = 0;
+
+    std::uint32_t maxReadRequestsOutstanding_;
+    std::atomic_uint32_t numReadRequestsOutstanding_ = 0;
+
+    std::size_t writeBatchSize_;
+
+    std::mutex throttleMutex_;
+    std::condition_variable throttleCv_;
+
+    std::mutex syncMutex_;
+    std::condition_variable syncCv_;
+
+    boost::asio::io_context ioc_;
+    std::optional<boost::asio::io_service::work> work_;
+
+    std::reference_wrapper<HandleType const> handle_;
+    std::thread thread_;
+
+    typename BackendCountersType::PtrType counters_;
+
+public:
+    using ResultOrErrorType = typename HandleType::ResultOrErrorType;
+    using StatementType = typename HandleType::StatementType;
+    using PreparedStatementType = typename HandleType::PreparedStatementType;
+    using FutureType = typename HandleType::FutureType;
+    using FutureWithCallbackType = typename HandleType::FutureWithCallbackType;
+    using ResultType = typename HandleType::ResultType;
+    using CompletionTokenType = boost::asio::yield_context;
+
+    /**
+     * @param settings The settings to use
+     * @param handle A handle to the cassandra database
+     */
+    DefaultExecutionStrategy(
+        Settings const& settings,
+        HandleType const& handle,
+        typename BackendCountersType::PtrType counters = BackendCountersType::make()
+    )
+        : maxWriteRequestsOutstanding_{settings.maxWriteRequestsOutstanding}
+        , maxReadRequestsOutstanding_{settings.maxReadRequestsOutstanding}
+        , writeBatchSize_{settings.writeBatchSize}
+        , work_{ioc_}
+        , handle_{std::cref(handle)}
+        , thread_{[this]() { ioc_.run(); }}
+        , counters_{std::move(counters)}
+    {
+        LOG(log_.info()) << "Max write requests outstanding is " << maxWriteRequestsOutstanding_
+                         << "; Max read requests outstanding is " << maxReadRequestsOutstanding_;
+    }
+
+    ~DefaultExecutionStrategy()
+    {
+        work_.reset();
+        ioc_.stop();
+        thread_.join();
+    }
+
+    /**
+     * @brief Wait for all async writes to finish before unblocking.
+     */
+    void
+    sync()
+    {
+        LOG(log_.debug()) << "Waiting to sync all writes...";
+        std::unique_lock<std::mutex> lck(syncMutex_);
+        syncCv_.wait(lck, [this]() { return finishedAllWriteRequests(); });
+        LOG(log_.debug()) << "Sync done.";
+    }
+
+    /**
+     * @return true if outstanding read requests allowance is exhausted; false otherwise
+     */
+    bool
+    isTooBusy() const
+    {
+        bool const result = numReadRequestsOutstanding_ >= maxReadRequestsOutstanding_;
+        if (result)
+            counters_->registerTooBusy();
+        return result;
+    }
+
+    /**
+     * @brief Blocking query execution used for writing data.
+     *
+     * Retries forever sleeping for 5 milliseconds between attempts.
+     */
+    ResultOrErrorType
+    writeSync(StatementType const& statement)
+    {
+        auto const startTime = std::chrono::steady_clock::now();
+        while (true) {
+            auto res = handle_.get().execute(statement);
+            if (res) {
+                counters_->registerWriteSync(startTime);
+                return res;
+            }
+
+            counters_->registerWriteSyncRetry();
+            LOG(log_.warn()) << "Cassandra sync write error, retrying: " << res.error();
+            std::this_thread::sleep_for(std::chrono::milliseconds(5));
+        }
+    }
+
+    /**
+     * @brief Blocking query execution used for writing data.
+     *
+     * Retries forever sleeping for 5 milliseconds between attempts.
+     */
+    template <typename... Args>
+    ResultOrErrorType
+    writeSync(PreparedStatementType const& preparedStatement, Args&&... args)
+    {
+        return writeSync(preparedStatement.bind(std::forward<Args>(args)...));
+    }
+
+    /**
+     * @brief Non-blocking query execution used for writing data.
+     *
+     * Retries forever with retry policy specified by @ref AsyncExecutor
+     *
+     * @param preparedStatement Statement to prepare and execute
+     * @param args Args to bind to the prepared statement
+     * @throw DatabaseTimeout on timeout
+     */
+    template <typename... Args>
+    void
+    write(PreparedStatementType const& preparedStatement, Args&&... args)
+    {
+        auto const startTime = std::chrono::steady_clock::now();
+
+        auto statement = preparedStatement.bind(std::forward<Args>(args)...);
+        incrementOutstandingRequestCount();
+
+        counters_->registerWriteStarted();
+        // Note: lifetime is controlled by std::shared_from_this internally
+        AsyncExecutor<std::decay_t<decltype(statement)>, HandleType>::run(
+            ioc_,
+            handle_,
+            std::move(statement),
+            [this, startTime](auto const&) {
+                decrementOutstandingRequestCount();
+
+                counters_->registerWriteFinished(startTime);
+            },
+            [this]() { counters_->registerWriteRetry(); }
+        );
+    }
+
+    /**
+     * @brief Non-blocking batched query execution used for writing data.
+     *
+     * Retries forever with retry policy specified by @ref AsyncExecutor.
+     *
+     * @param statements Vector of statements to execute as a batch
+     * @throw DatabaseTimeout on timeout
+     */
+    void
+    write(std::vector<StatementType>&& statements)
+    {
+        if (statements.empty())
+            return;
+
+        util::forEachBatch(std::move(statements), writeBatchSize_, [this](auto begin, auto end) {
+            auto const startTime = std::chrono::steady_clock::now();
+            auto chunk = std::vector<StatementType>{};
+
+            chunk.reserve(std::distance(begin, end));
+            std::move(begin, end, std::back_inserter(chunk));
+
+            incrementOutstandingRequestCount();
+            counters_->registerWriteStarted();
+
+            // Note: lifetime is controlled by std::shared_from_this internally
+            AsyncExecutor<std::decay_t<decltype(chunk)>, HandleType>::run(
+                ioc_,
+                handle_,
+                std::move(chunk),
+                [this, startTime](auto const&) {
+                    decrementOutstandingRequestCount();
+                    counters_->registerWriteFinished(startTime);
+                },
+                [this]() { counters_->registerWriteRetry(); }
+            );
+        });
+    }
+
+    /**
+     * @brief Coroutine-based query execution used for reading data.
+     *
+     * Retries forever until successful or throws an exception on timeout.
+     *
+     * @param token Completion token (yield_context)
+     * @param preparedStatement Statement to prepare and execute
+     * @param args Args to bind to the prepared statement
+     * @throw DatabaseTimeout on timeout
+     * @return ResultType or error wrapped in Expected
+     */
+    template <typename... Args>
+    [[maybe_unused]] ResultOrErrorType
+    read(CompletionTokenType token, PreparedStatementType const& preparedStatement, Args&&... args)
+    {
+        return read(token, preparedStatement.bind(std::forward<Args>(args)...));
+    }
+
+    /**
+     * @brief Coroutine-based query execution used for reading data.
+     *
+     * Retries forever until successful or throws an exception on timeout.
+     *
+     * @param token Completion token (yield_context)
+     * @param statements Statements to execute in a batch
+     * @throw DatabaseTimeout on timeout
+     * @return ResultType or error wrapped in Expected
+     */
+    [[maybe_unused]] ResultOrErrorType
+    read(CompletionTokenType token, std::vector<StatementType> const& statements)
+    {
+        auto const startTime = std::chrono::steady_clock::now();
+
+        auto const numStatements = statements.size();
+        std::optional<FutureWithCallbackType> future;
+        counters_->registerReadStarted(numStatements);
+
+        // todo: perhaps use policy instead
+        while (true) {
+            numReadRequestsOutstanding_ += numStatements;
+
+            auto init = [this, &statements, &future]<typename Self>(Self& self) {
+                auto sself = std::make_shared<Self>(std::move(self));
+
+                future.emplace(handle_.get().asyncExecute(statements, [sself](auto&& res) mutable {
+                    boost::asio::post(
+                        boost::asio::get_associated_executor(*sself),
+                        [sself, res = std::forward<decltype(res)>(res)]() mutable { sself->complete(std::move(res)); }
+                    );
+                }));
+            };
+
+            auto res = boost::asio::async_compose<CompletionTokenType, void(ResultOrErrorType)>(
+                init, token, boost::asio::get_associated_executor(token)
+            );
+            numReadRequestsOutstanding_ -= numStatements;
+
+            if (res) {
+                counters_->registerReadFinished(startTime, numStatements);
+                return res;
+            }
+
+            LOG(log_.error()) << "Failed batch read in coroutine: " << res.error();
+            try {
+                throwErrorIfNeeded(res.error());
+            } catch (...) {
+                counters_->registerReadError(numStatements);
+                throw;
+            }
+            counters_->registerReadRetry(numStatements);
+        }
+    }
+
+    /**
+     * @brief Coroutine-based query execution used for reading data.
+     *
+     * Retries forever until successful or throws an exception on timeout.
+     *
+     * @param token Completion token (yield_context)
+     * @param statement Statement to execute
+     * @throw DatabaseTimeout on timeout
+     * @return ResultType or error wrapped in Expected
+     */
+    [[maybe_unused]] ResultOrErrorType
+    read(CompletionTokenType token, StatementType const& statement)
+    {
+        auto const startTime = std::chrono::steady_clock::now();
+
+        std::optional<FutureWithCallbackType> future;
+        counters_->registerReadStarted();
+
+        // todo: perhaps use policy instead
+        while (true) {
+            ++numReadRequestsOutstanding_;
+            auto init = [this, &statement, &future]<typename Self>(Self& self) {
+                auto sself = std::make_shared<Self>(std::move(self));
+
+                future.emplace(handle_.get().asyncExecute(statement, [sself](auto&& res) mutable {
+                    boost::asio::post(
+                        boost::asio::get_associated_executor(*sself),
+                        [sself, res = std::forward<decltype(res)>(res)]() mutable { sself->complete(std::move(res)); }
+                    );
+                }));
+            };
+
+            auto res = boost::asio::async_compose<CompletionTokenType, void(ResultOrErrorType)>(
+                init, token, boost::asio::get_associated_executor(token)
+            );
+            --numReadRequestsOutstanding_;
+
+            if (res) {
+                counters_->registerReadFinished(startTime);
+                return res;
+            }
+
+            LOG(log_.error()) << "Failed read in coroutine: " << res.error();
+            try {
+                throwErrorIfNeeded(res.error());
+            } catch (...) {
+                counters_->registerReadError();
+                throw;
+            }
+            counters_->registerReadRetry();
+        }
+    }
+
+    /**
+     * @brief Coroutine-based query execution used for reading data.
+     *
+     * Attempts to execute each statement. On any error the whole vector will be
+     * discarded and exception will be thrown.
+     *
+     * @param token Completion token (yield_context)
+     * @param statements Statements to execute
+     * @throw DatabaseTimeout on db error
+     * @return Vector of results
+     */
+    std::vector<ResultType>
+    readEach(CompletionTokenType token, std::vector<StatementType> const& statements)
+    {
+        auto const startTime = std::chrono::steady_clock::now();
+
+        std::atomic_uint64_t errorsCount = 0u;
+        std::atomic_int numOutstanding = statements.size();
+        numReadRequestsOutstanding_ += statements.size();
+
+        auto futures = std::vector<FutureWithCallbackType>{};
+        futures.reserve(numOutstanding);
+        counters_->registerReadStarted(statements.size());
+
+        auto init = [this, &statements, &futures, &errorsCount, &numOutstanding]<typename Self>(Self& self) {
+            auto sself = std::make_shared<Self>(std::move(self));
+            auto executionHandler = [&errorsCount, &numOutstanding, sself](auto const& res) mutable {
+                if (not res)
+                    ++errorsCount;
+
+                // when all async operations complete unblock the result
+                if (--numOutstanding == 0) {
+                    boost::asio::post(boost::asio::get_associated_executor(*sself), [sself]() mutable {
+                        sself->complete();
+                    });
+                }
+            };
+
+            std::transform(
+                std::cbegin(statements),
+                std::cend(statements),
+                std::back_inserter(futures),
+                [this, &executionHandler](auto const& statement) {
+                    return handle_.get().asyncExecute(statement, executionHandler);
+                }
+            );
+        };
+
+        boost::asio::async_compose<CompletionTokenType, void()>(
+            init, token, boost::asio::get_associated_executor(token)
+        );
+        numReadRequestsOutstanding_ -= statements.size();
+
+        if (errorsCount > 0) {
+            ASSERT(errorsCount <= statements.size(), "Errors number cannot exceed statements number");
+            counters_->registerReadError(errorsCount);
+            counters_->registerReadFinished(startTime, statements.size() - errorsCount);
+            throw DatabaseTimeout{};
+        }
+        counters_->registerReadFinished(startTime, statements.size());
+
+        std::vector<ResultType> results;
+        results.reserve(futures.size());
+
+        // it's safe to call blocking get on futures here as we already waited for the coroutine to resume above.
+        std::transform(
+            std::make_move_iterator(std::begin(futures)),
+            std::make_move_iterator(std::end(futures)),
+            std::back_inserter(results),
+            [](auto&& future) {
+                auto entry = future.get();
+                auto&& res = entry.value();
+                return std::move(res);
+            }
+        );
+
+        ASSERT(
+            futures.size() == statements.size(),
+            "Futures size must be equal to statements size. Got {} and {}",
+            futures.size(),
+            statements.size()
+        );
+        ASSERT(
+            results.size() == statements.size(),
+            "Results size must be equal to statements size. Got {} and {}",
+            results.size(),
+            statements.size()
+        );
+        return results;
+    }
+
+    /**
+     * @brief Get statistics about the backend.
+     */
+    boost::json::object
+    stats() const
+    {
+        return counters_->report();
+    }
+
+private:
+    void
+    incrementOutstandingRequestCount()
+    {
+        {
+            std::unique_lock<std::mutex> lck(throttleMutex_);
+            if (!canAddWriteRequest()) {
+                LOG(log_.trace()) << "Max outstanding requests reached. "
+                                  << "Waiting for other requests to finish";
+                throttleCv_.wait(lck, [this]() { return canAddWriteRequest(); });
+            }
+        }
+        ++numWriteRequestsOutstanding_;
+    }
+
+    void
+    decrementOutstandingRequestCount()
+    {
+        // sanity check
+        ASSERT(numWriteRequestsOutstanding_ > 0, "Decrementing num outstanding below 0");
+        size_t const cur = (--numWriteRequestsOutstanding_);
+        {
+            // mutex lock required to prevent race condition around spurious
+            // wakeup
+            std::lock_guard const lck(throttleMutex_);
+            throttleCv_.notify_one();
+        }
+        if (cur == 0) {
+            // mutex lock required to prevent race condition around spurious
+            // wakeup
+            std::lock_guard const lck(syncMutex_);
+            syncCv_.notify_one();
+        }
+    }
+
+    bool
+    canAddWriteRequest() const
+    {
+        return numWriteRequestsOutstanding_ < maxWriteRequestsOutstanding_;
+    }
+
+    bool
+    finishedAllWriteRequests() const
+    {
+        return numWriteRequestsOutstanding_ == 0;
+    }
+
+    void
+    throwErrorIfNeeded(CassandraError err) const
+    {
+        if (err.isTimeout())
+            throw DatabaseTimeout();
+
+        if (err.isInvalidQuery())
+            throw std::runtime_error("Invalid query");
+    }
+};
+
+}  // namespace data::cassandra::detail

src/data/cassandra/impl/Future.cpp

@@ -17,18 +17,25 @@
 */
 //==============================================================================
 
-#include <backend/cassandra/Error.h>
-#include <backend/cassandra/impl/Future.h>
-#include <backend/cassandra/impl/Result.h>
+#include "data/cassandra/impl/Future.hpp"
 
-#include <exception>
-#include <vector>
+#include "data/cassandra/Error.hpp"
+#include "data/cassandra/Types.hpp"
+#include "data/cassandra/impl/ManagedObject.hpp"
+#include "data/cassandra/impl/Result.hpp"
+
+#include <cassandra.h>
+
+#include <cstddef>
+#include <memory>
+#include <string>
+#include <utility>
 
 namespace {
-static constexpr auto futureDeleter = [](CassFuture* ptr) { cass_future_free(ptr); };
+constexpr auto futureDeleter = [](CassFuture* ptr) { cass_future_free(ptr); };
 }  // namespace
 
-namespace Backend::Cassandra::detail {
+namespace data::cassandra::detail {
 
 /* implicit */ Future::Future(CassFuture* ptr) : ManagedObject{ptr, futureDeleter}
 {
@@ -37,11 +44,10 @@ namespace Backend::Cassandra::detail {
 MaybeError
 Future::await() const
 {
-    if (auto const rc = cass_future_error_code(*this); rc)
-    {
-        auto errMsg = [this](std::string label) {
-            char const* message;
-            std::size_t len;
+    if (auto const rc = cass_future_error_code(*this); rc) {
+        auto errMsg = [this](std::string const& label) {
+            char const* message = nullptr;
+            std::size_t len = 0;
             cass_future_error_message(*this, &message, &len);
             return label + ": " + std::string{message, len};
         }(cass_error_desc(rc));
@@ -53,45 +59,42 @@ Future::await() const
 ResultOrError
 Future::get() const
 {
-    if (auto const rc = cass_future_error_code(*this); rc)
-    {
-        auto const errMsg = [this](std::string label) {
-            char const* message;
-            std::size_t len;
+    if (auto const rc = cass_future_error_code(*this); rc) {
+        auto const errMsg = [this](std::string const& label) {
+            char const* message = nullptr;
+            std::size_t len = 0;
             cass_future_error_message(*this, &message, &len);
             return label + ": " + std::string{message, len};
         }("future::get()");
         return Error{CassandraError{errMsg, rc}};
     }
-    else
-    {
-        return Result{cass_future_get_result(*this)};
-    }
+
+    return Result{cass_future_get_result(*this)};
 }
 
 void
 invokeHelper(CassFuture* ptr, void* cbPtr)
 {
     // Note: can't use Future{ptr}.get() because double free will occur :/
-    auto* cb = static_cast<FutureWithCallback::fn_t*>(cbPtr);
-    if (auto const rc = cass_future_error_code(ptr); rc)
-    {
-        auto const errMsg = [&ptr](std::string label) {
-            char const* message;
-            std::size_t len;
+    // Note2: we are moving/copying it locally as a workaround for an issue we are seeing from asio recently.
+    // stackoverflow.com/questions/77004137/boost-asio-async-compose-gets-stuck-under-load
+    auto* cb = static_cast<FutureWithCallback::FnType*>(cbPtr);
+    auto local = std::make_unique<FutureWithCallback::FnType>(std::move(*cb));
+    if (auto const rc = cass_future_error_code(ptr); rc) {
+        auto const errMsg = [&ptr](std::string const& label) {
+            char const* message = nullptr;
+            std::size_t len = 0;
             cass_future_error_message(ptr, &message, &len);
             return label + ": " + std::string{message, len};
         }("invokeHelper");
-        (*cb)(Error{CassandraError{errMsg, rc}});
-    }
-    else
-    {
-        (*cb)(Result{cass_future_get_result(ptr)});
+        (*local)(Error{CassandraError{errMsg, rc}});
+    } else {
+        (*local)(Result{cass_future_get_result(ptr)});
     }
 }
 
-/* implicit */ FutureWithCallback::FutureWithCallback(CassFuture* ptr, fn_t&& cb)
-    : Future{ptr}, cb_{std::make_unique<fn_t>(std::move(cb))}
+/* implicit */ FutureWithCallback::FutureWithCallback(CassFuture* ptr, FnType&& cb)
+    : Future{ptr}, cb_{std::make_unique<FnType>(std::move(cb))}
 {
     // Instead of passing `this` as the userdata void*, we pass the address of
     // the callback itself which will survive std::move of the
@@ -99,4 +102,4 @@ invokeHelper(CassFuture* ptr, void* cbPtr)
     cass_future_set_callback(*this, &invokeHelper, cb_.get());
 }
 
-}  // namespace Backend::Cassandra::detail
+}  // namespace data::cassandra::detail

src/data/cassandra/impl/Future.hpp

@@ -19,15 +19,17 @@
 
 #pragma once
 
-#include <backend/cassandra/Types.h>
-#include <backend/cassandra/impl/ManagedObject.h>
+#include "data/cassandra/Types.hpp"
+#include "data/cassandra/impl/ManagedObject.hpp"
 
 #include <cassandra.h>
 
-namespace Backend::Cassandra::detail {
+#include <functional>
+#include <memory>
 
-struct Future : public ManagedObject<CassFuture>
-{
+namespace data::cassandra::detail {
+
+struct Future : public ManagedObject<CassFuture> {
     /* implicit */ Future(CassFuture* ptr);
 
     MaybeError
@@ -38,21 +40,20 @@ struct Future : public ManagedObject<CassFuture>
 };
 
 void
-invokeHelper(CassFuture* ptr, void* self);
+invokeHelper(CassFuture* ptr, void* cbPtr);
 
-class FutureWithCallback : public Future
-{
+class FutureWithCallback : public Future {
 public:
-    using fn_t = std::function<void(ResultOrError)>;
-    using fn_ptr_t = std::unique_ptr<fn_t>;
+    using FnType = std::function<void(ResultOrError)>;
+    using FnPtrType = std::unique_ptr<FnType>;
 
-    /* implicit */ FutureWithCallback(CassFuture* ptr, fn_t&& cb);
+    /* implicit */ FutureWithCallback(CassFuture* ptr, FnType&& cb);
     FutureWithCallback(FutureWithCallback const&) = delete;
     FutureWithCallback(FutureWithCallback&&) = default;
 
 private:
-    /*! Wrapped in a unique_ptr so it can survive std::move :/ */
-    fn_ptr_t cb_;
+    /** Wrapped in a unique_ptr so it can survive std::move :/ */
+    FnPtrType cb_;
 };
 
-}  // namespace Backend::Cassandra::detail
+}  // namespace data::cassandra::detail

src/data/cassandra/impl/ManagedObject.hpp

@@ -20,12 +20,12 @@
 #pragma once
 
 #include <memory>
+#include <stdexcept>
 
-namespace Backend::Cassandra::detail {
+namespace data::cassandra::detail {
 
 template <typename Managed>
-class ManagedObject
-{
+class ManagedObject {
 protected:
     std::unique_ptr<Managed, void (*)(Managed*)> ptr_;
 
@@ -36,12 +36,11 @@ public:
         if (rawPtr == nullptr)
             throw std::runtime_error("Could not create DB object - got nullptr");
     }
-    ManagedObject(ManagedObject&&) = default;
 
-    operator Managed* const() const
+    operator Managed*() const
     {
         return ptr_.get();
     }
 };
 
-}  // namespace Backend::Cassandra::detail
+}  // namespace data::cassandra::detail