Refactor source (#1171)

For #51

src/util/Retry.cpp

@@ -0,0 +1,115 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of clio: https://github.com/XRPLF/clio
+    Copyright (c) 2024, 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 "util/Retry.hpp"
+
+#include <boost/asio/io_context.hpp>
+#include <boost/asio/strand.hpp>
+
+#include <algorithm>
+#include <chrono>
+#include <cstddef>
+#include <memory>
+#include <utility>
+
+namespace util {
+
+RetryStrategy::RetryStrategy(std::chrono::steady_clock::duration delay) : initialDelay_(delay), delay_(delay)
+{
+}
+
+std::chrono::steady_clock::duration
+RetryStrategy::getDelay() const
+{
+    return delay_;
+}
+
+void
+RetryStrategy::increaseDelay()
+{
+    delay_ = nextDelay();
+}
+
+void
+RetryStrategy::reset()
+{
+    delay_ = initialDelay_;
+}
+
+Retry::Retry(RetryStrategyPtr strategy, boost::asio::strand<boost::asio::io_context::executor_type> strand)
+    : strategy_(std::move(strategy)), timer_(strand.get_inner_executor())
+{
+}
+
+Retry::~Retry()
+{
+    cancel();
+}
+
+void
+Retry::cancel()
+{
+    timer_.cancel();
+}
+
+size_t
+Retry::attemptNumber() const
+{
+    return attemptNumber_;
+}
+
+std::chrono::steady_clock::duration
+Retry::delayValue() const
+{
+    return strategy_->getDelay();
+}
+
+void
+Retry::reset()
+{
+    attemptNumber_ = 0;
+    strategy_->reset();
+}
+
+ExponentialBackoffStrategy::ExponentialBackoffStrategy(
+    std::chrono::steady_clock::duration delay,
+    std::chrono::steady_clock::duration maxDelay
+)
+    : RetryStrategy(delay), maxDelay_(maxDelay)
+{
+}
+
+std::chrono::steady_clock::duration
+ExponentialBackoffStrategy::nextDelay() const
+{
+    auto const next = getDelay() * 2;
+    return std::min(next, maxDelay_);
+}
+
+Retry
+makeRetryExponentialBackoff(
+    std::chrono::steady_clock::duration delay,
+    std::chrono::steady_clock::duration maxDelay,
+    boost::asio::strand<boost::asio::io_context::executor_type> strand
+)
+{
+    return Retry(std::make_unique<ExponentialBackoffStrategy>(delay, maxDelay), std::move(strand));
+}
+
+}  // namespace util