Implement ledger_range rpc handler (#548)

Fixes #549

CMakeLists.txt

@@ -62,6 +62,7 @@ target_sources(clio PRIVATE
   src/rpc/ngHandlers/Tx.cpp
   src/rpc/ngHandlers/GatewayBalances.cpp
   src/rpc/ngHandlers/LedgerEntry.cpp
+  src/rpc/ngHandlers/LedgerRange.cpp
   src/rpc/ngHandlers/BookOffers.cpp
   ## RPC Methods
   # Account
@@ -128,6 +129,7 @@ if(BUILD_TESTS)
     unittests/rpc/handlers/TxTest.cpp
     unittests/rpc/handlers/GatewayBalancesTest.cpp
     unittests/rpc/handlers/LedgerEntryTest.cpp
+    unittests/rpc/handlers/LedgerRangeTest.cpp
     unittests/rpc/handlers/BookOffersTest.cpp)
   include(CMake/deps/gtest.cmake)
 

src/rpc/ngHandlers/LedgerRange.cpp

@@ -0,0 +1,54 @@
+//------------------------------------------------------------------------------
+/*
+    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 <rpc/RPCHelpers.h>
+#include <rpc/ngHandlers/LedgerRange.h>
+
+#include <optional>
+
+namespace RPCng {
+
+LedgerRangeHandler::Result
+LedgerRangeHandler::process() const
+{
+    if (auto const maybeRange = sharedPtrBackend_->fetchLedgerRange();
+        maybeRange)
+    {
+        return Output{*maybeRange};
+    }
+    else
+    {
+        return Error{
+            RPC::Status{RPC::RippledError::rpcNOT_READY, "rangeNotFound"}};
+    };
+}
+
+void
+tag_invoke(
+    boost::json::value_from_tag,
+    boost::json::value& jv,
+    LedgerRangeHandler::Output const& output)
+{
+    jv = boost::json::object{
+        {JS(ledger_index_min), output.range.minSequence},
+        {JS(ledger_index_max), output.range.maxSequence},
+    };
+}
+
+}  // namespace RPCng

src/rpc/ngHandlers/LedgerRange.h

@@ -0,0 +1,59 @@
+//------------------------------------------------------------------------------
+/*
+    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/BackendInterface.h>
+#include <rpc/common/Types.h>
+
+#include <boost/json.hpp>
+
+#include <memory>
+
+namespace RPCng {
+
+class LedgerRangeHandler
+{
+    std::shared_ptr<BackendInterface> sharedPtrBackend_;
+
+public:
+    struct Output
+    {
+        Backend::LedgerRange range;
+    };
+
+    using Result = HandlerReturnType<Output>;
+
+    LedgerRangeHandler(
+        std::shared_ptr<BackendInterface> const& sharedPtrBackend)
+        : sharedPtrBackend_(sharedPtrBackend)
+    {
+    }
+
+    Result
+    process() const;
+};
+
+void
+tag_invoke(
+    boost::json::value_from_tag,
+    boost::json::value& jv,
+    LedgerRangeHandler::Output const& output);
+
+}  // namespace RPCng

unittests/rpc/handlers/LedgerRangeTest.cpp

@@ -0,0 +1,71 @@
+//------------------------------------------------------------------------------
+/*
+    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 <rpc/common/AnyHandler.h>
+#include <rpc/ngHandlers/LedgerRange.h>
+#include <util/Fixtures.h>
+
+#include <fmt/core.h>
+
+using namespace RPCng;
+namespace json = boost::json;
+using namespace testing;
+
+constexpr static auto RANGEMIN = 10;
+constexpr static auto RANGEMAX = 30;
+
+class RPCLedgerRangeTest : public HandlerBaseTest
+{
+};
+
+TEST_F(RPCLedgerRangeTest, LedgerRangeNotFound)
+{
+    auto const handler = AnyHandler{LedgerRangeHandler{mockBackendPtr}};
+    auto const req = json::parse("{}");
+    auto const output = handler.process(req);
+    ASSERT_FALSE(output);
+    auto const err = RPC::makeError(output.error());
+    EXPECT_EQ(err.at("error").as_string(), "notReady");
+    EXPECT_EQ(err.at("error_message").as_string(), "rangeNotFound");
+}
+
+TEST_F(RPCLedgerRangeTest, LedgerRangeMinMaxSame)
+{
+    mockBackendPtr->updateRange(RANGEMIN);
+    auto const handler = AnyHandler{LedgerRangeHandler{mockBackendPtr}};
+    auto const req = json::parse("{}");
+    auto const output = handler.process(req);
+    ASSERT_TRUE(output);
+    auto const json = output.value();
+    EXPECT_EQ(json.at("ledger_index_min").as_uint64(), RANGEMIN);
+    EXPECT_EQ(json.at("ledger_index_max").as_uint64(), RANGEMIN);
+}
+
+TEST_F(RPCLedgerRangeTest, LedgerRangeFullySet)
+{
+    mockBackendPtr->updateRange(RANGEMIN);
+    mockBackendPtr->updateRange(RANGEMAX);
+    auto const handler = AnyHandler{LedgerRangeHandler{mockBackendPtr}};
+    auto const req = json::parse("{}");
+    auto const output = handler.process(req);
+    ASSERT_TRUE(output);
+    auto const json = output.value();
+    EXPECT_EQ(json.at("ledger_index_min").as_uint64(), RANGEMIN);
+    EXPECT_EQ(json.at("ledger_index_max").as_uint64(), RANGEMAX);
+}