From 5ce3fda27f5ab1a0dc2f3068edb1603003d90bcd Mon Sep 17 00:00:00 2001 From: Bee Klimt Date: Fri, 22 May 2026 23:02:27 -0700 Subject: [PATCH 01/17] feat: orchestrator switches to FDv1 fallback on directive --- .../source/ifdv2_synchronizer_factory.hpp | 2 + .../data_systems/fdv2/fdv2_data_system.cpp | 15 +- .../src/data_systems/fdv2/source_manager.cpp | 16 ++- .../src/data_systems/fdv2/source_manager.hpp | 16 ++- .../tests/fdv2_data_system_test.cpp | 132 ++++++++++++++++++ libs/server-sdk/tests/source_manager_test.cpp | 72 +++++++++- 6 files changed, 243 insertions(+), 10 deletions(-) diff --git a/libs/server-sdk/src/data_interfaces/source/ifdv2_synchronizer_factory.hpp b/libs/server-sdk/src/data_interfaces/source/ifdv2_synchronizer_factory.hpp index fc3c6421a..ba130e768 100644 --- a/libs/server-sdk/src/data_interfaces/source/ifdv2_synchronizer_factory.hpp +++ b/libs/server-sdk/src/data_interfaces/source/ifdv2_synchronizer_factory.hpp @@ -14,6 +14,8 @@ class IFDv2SynchronizerFactory { public: virtual std::unique_ptr Build() = 0; + [[nodiscard]] virtual bool IsFDv1Fallback() const { return false; } + virtual ~IFDv2SynchronizerFactory() = default; IFDv2SynchronizerFactory(IFDv2SynchronizerFactory const&) = delete; IFDv2SynchronizerFactory(IFDv2SynchronizerFactory&&) = delete; diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp index b3caa5aba..ba66bfe4f 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp @@ -185,6 +185,12 @@ void FDv2DataSystem::OnInitializerResult( if (closed_ || got_shutdown) { return; } + if (result.fdv1_fallback) { + LD_LOG(logger_, LogLevel::kInfo) + << Identity() << ": FDv1 fallback engaged"; + source_manager_.SwitchToFDv1Fallback(); + got_basis = true; + } } if (got_basis) { @@ -349,7 +355,14 @@ void FDv2DataSystem::OnSynchronizerResult( active_conditions_.reset(); return; } - if (advance) { + if (result.fdv1_fallback) { + LD_LOG(logger_, LogLevel::kInfo) + << Identity() << ": FDv1 fallback engaged"; + source_manager_.SwitchToFDv1Fallback(); + active_synchronizer_.reset(); + active_conditions_.reset(); + advance = true; + } else if (advance) { source_manager_.BlockCurrentSynchronizer(); active_synchronizer_.reset(); active_conditions_.reset(); diff --git a/libs/server-sdk/src/data_systems/fdv2/source_manager.cpp b/libs/server-sdk/src/data_systems/fdv2/source_manager.cpp index 362f13efd..4af2405a6 100644 --- a/libs/server-sdk/src/data_systems/fdv2/source_manager.cpp +++ b/libs/server-sdk/src/data_systems/fdv2/source_manager.cpp @@ -11,9 +11,11 @@ SourceManager::SourceManager( std::vector> factories) { synchronizers_.reserve(factories.size()); for (auto& factory : factories) { - synchronizers_.push_back( - SynchronizerFactoryWithState{std::move(factory), State::kAvailable, - /*is_fdv1_fallback=*/false}); + bool const is_fdv1_fallback = factory->IsFDv1Fallback(); + synchronizers_.push_back(SynchronizerFactoryWithState{ + std::move(factory), + is_fdv1_fallback ? State::kBlocked : State::kAvailable, + is_fdv1_fallback}); } } @@ -44,6 +46,14 @@ void SourceManager::ResetSourceIndex() { synchronizer_index_ = -1; } +void SourceManager::SwitchToFDv1Fallback() { + for (auto& entry : synchronizers_) { + entry.state = + entry.is_fdv1_fallback ? State::kAvailable : State::kBlocked; + } + synchronizer_index_ = -1; +} + bool SourceManager::IsPrimeSynchronizer() const { for (std::size_t i = 0; i < synchronizers_.size(); ++i) { if (synchronizers_[i].state == State::kAvailable) { diff --git a/libs/server-sdk/src/data_systems/fdv2/source_manager.hpp b/libs/server-sdk/src/data_systems/fdv2/source_manager.hpp index 1f310bfed..bd2347ccf 100644 --- a/libs/server-sdk/src/data_systems/fdv2/source_manager.hpp +++ b/libs/server-sdk/src/data_systems/fdv2/source_manager.hpp @@ -23,8 +23,7 @@ namespace launchdarkly::server_side::data_systems { * by recovery, which wants to fall back to the most-preferred Available * synchronizer. * - * Each factory also carries an is_fdv1_fallback flag, currently always - * false. TODO: populate when the FDv1 fallback directive is implemented. + * Factories whose IsFDv1Fallback() returns true start in the Blocked state. * * Not thread-safe. The caller is responsible for serializing all calls. */ @@ -54,6 +53,14 @@ class SourceManager { */ void ResetSourceIndex(); + /** + * Blocks every non-FDv1 factory and unblocks the FDv1 fallback factory, + * if one was configured. Resets the iteration cursor so the next call to + * NextSynchronizer returns the FDv1 fallback. If no FDv1 fallback factory + * was configured, every factory is left blocked. + */ + void SwitchToFDv1Fallback(); + /** * Returns true if the currently tracked factory is the first Available * factory in the list. Returns false if no factory is currently tracked. @@ -73,9 +80,8 @@ class SourceManager { [[nodiscard]] std::size_t SynchronizerCount() const; /** - * Returns true if the currently tracked factory was configured as the - * FDv1 fallback synchronizer. Always false until the FDv1 fallback - * directive is implemented. + * Returns true if the currently tracked factory is the FDv1 fallback + * synchronizer. */ [[nodiscard]] bool IsCurrentSynchronizerFDv1Fallback() const; diff --git a/libs/server-sdk/tests/fdv2_data_system_test.cpp b/libs/server-sdk/tests/fdv2_data_system_test.cpp index 48d9b49d1..72ef65ff4 100644 --- a/libs/server-sdk/tests/fdv2_data_system_test.cpp +++ b/libs/server-sdk/tests/fdv2_data_system_test.cpp @@ -145,6 +145,15 @@ class OneShotSynchronizerFactory : public IFDv2SynchronizerFactory { std::unique_ptr source_; }; +class FDv1FallbackOneShotFactory : public OneShotSynchronizerFactory { + public: + explicit FDv1FallbackOneShotFactory( + std::unique_ptr source) + : OneShotSynchronizerFactory(std::move(source)) {} + + bool IsFDv1Fallback() const override { return true; } +}; + // Returns each pre-supplied source in order on successive Build() calls. // Returns nullptr once the supply is exhausted. Used in tests that exercise // wrap-around or recovery, where the same factory is built more than once. @@ -1090,6 +1099,129 @@ TEST(FDv2DataSystemTest, SingleSynchronizerHasNoFallbackArmed) { status_manager.Status().State()); } +// ============================================================================ +// FDv1 fallback directive +// ============================================================================ + +TEST(FDv2DataSystemTest, SynchronizerFdv1FlagSwitchesToFdv1Adapter) { + auto logger = MakeNullLogger(); + boost::asio::io_context ioc; + data_components::DataSourceStatusManager status_manager; + + // FDv2 synchronizer emits a ChangeSet with the directive, then closes. + auto fdv2_sync = + std::make_unique(std::vector{[]() { + FDv2SourceResult r{FDv2SourceResult::ChangeSet{ + data_model::ChangeSet{ + data_model::ChangeSetType::kNone, + {}, + data_model::Selector{}}}}; + r.fdv1_fallback = true; + return r; + }()}); + auto fdv2_factory = + std::make_unique(std::move(fdv2_sync)); + + // FDv1 adapter returns Shutdown when reached, ending orchestration. + auto fdv1_sync = + std::make_unique(std::vector{}); + auto fdv1_factory = + std::make_unique(std::move(fdv1_sync)); + auto* fdv1_factory_ptr = fdv1_factory.get(); + + std::vector> synchronizers; + synchronizers.push_back(std::move(fdv2_factory)); + synchronizers.push_back(std::move(fdv1_factory)); + + FDv2DataSystem ds({}, std::move(synchronizers), + /*fallback_condition_factory=*/nullptr, + /*recovery_condition_factory=*/nullptr, + ioc.get_executor(), &status_manager, logger); + ds.Initialize(); + ioc.run(); + + EXPECT_EQ(1, fdv1_factory_ptr->build_count_); +} + +TEST(FDv2DataSystemTest, SynchronizerFdv1FlagWithoutAdapterTransitionsOff) { + auto logger = MakeNullLogger(); + boost::asio::io_context ioc; + data_components::DataSourceStatusManager status_manager; + + auto fdv2_sync = + std::make_unique(std::vector{[]() { + FDv2SourceResult r{ + FDv2SourceResult::Interrupted{FDv2SourceResult::ErrorInfo{ + FDv2SourceResult::ErrorInfo::ErrorKind::kErrorResponse, + /*status_code=*/418, "directive", + std::chrono::system_clock::now()}}}; + r.fdv1_fallback = true; + return r; + }()}); + auto fdv2_factory = + std::make_unique(std::move(fdv2_sync)); + + std::vector> synchronizers; + synchronizers.push_back(std::move(fdv2_factory)); + + FDv2DataSystem ds({}, std::move(synchronizers), + /*fallback_condition_factory=*/nullptr, + /*recovery_condition_factory=*/nullptr, + ioc.get_executor(), &status_manager, logger); + ds.Initialize(); + ioc.run(); + + EXPECT_EQ(DataSourceStatus::DataSourceState::kOff, + status_manager.Status().State()); +} + +TEST(FDv2DataSystemTest, InitializerFdv1FlagSwitchesToFdv1Adapter) { + auto logger = MakeNullLogger(); + boost::asio::io_context ioc; + data_components::DataSourceStatusManager status_manager; + + // Initializer returns Interrupted with the directive set. + FDv2SourceResult init_result{ + FDv2SourceResult::Interrupted{FDv2SourceResult::ErrorInfo{ + FDv2SourceResult::ErrorInfo::ErrorKind::kErrorResponse, + /*status_code=*/418, "directive", + std::chrono::system_clock::now()}}}; + init_result.fdv1_fallback = true; + auto initializer = + std::make_unique(std::move(init_result)); + + std::vector> initializers; + initializers.push_back( + std::make_unique(std::move(initializer))); + + auto fdv2_sync = + std::make_unique(std::vector{}); + auto fdv2_factory = + std::make_unique(std::move(fdv2_sync)); + auto* fdv2_factory_ptr = fdv2_factory.get(); + + auto fdv1_sync = + std::make_unique(std::vector{}); + auto fdv1_factory = + std::make_unique(std::move(fdv1_sync)); + auto* fdv1_factory_ptr = fdv1_factory.get(); + + std::vector> synchronizers; + synchronizers.push_back(std::move(fdv2_factory)); + synchronizers.push_back(std::move(fdv1_factory)); + + FDv2DataSystem ds(std::move(initializers), std::move(synchronizers), + /*fallback_condition_factory=*/nullptr, + /*recovery_condition_factory=*/nullptr, + ioc.get_executor(), &status_manager, logger); + ds.Initialize(); + ioc.run(); + + // FDv2 synchronizer was skipped; FDv1 adapter was built and ran. + EXPECT_EQ(0, fdv2_factory_ptr->build_count_); + EXPECT_EQ(1, fdv1_factory_ptr->build_count_); +} + // ============================================================================ // Destruction protocol: in-flight orchestration // ============================================================================ diff --git a/libs/server-sdk/tests/source_manager_test.cpp b/libs/server-sdk/tests/source_manager_test.cpp index 244ca6400..77b207b46 100644 --- a/libs/server-sdk/tests/source_manager_test.cpp +++ b/libs/server-sdk/tests/source_manager_test.cpp @@ -43,6 +43,11 @@ class CountingFactory : public IFDv2SynchronizerFactory { int build_count = 0; }; +class FDv1FallbackFactory : public CountingFactory { + public: + bool IsFDv1Fallback() const override { return true; } +}; + } // namespace TEST(SourceManagerTest, EmptyManagerReportsZeroAvailable) { @@ -176,7 +181,7 @@ TEST(SourceManagerTest, ResetSourceIndexSkipsBlockedFirstFactory) { EXPECT_EQ(1, f1_ptr->build_count); } -TEST(SourceManagerTest, IsCurrentSynchronizerFDv1FallbackAlwaysFalse) { +TEST(SourceManagerTest, IsCurrentSynchronizerFDv1FallbackFalseForFDv2Factory) { auto f0 = std::make_unique(); std::vector> factories; factories.push_back(std::move(f0)); @@ -185,3 +190,68 @@ TEST(SourceManagerTest, IsCurrentSynchronizerFDv1FallbackAlwaysFalse) { mgr.NextSynchronizer(); EXPECT_FALSE(mgr.IsCurrentSynchronizerFDv1Fallback()); } + +TEST(SourceManagerTest, FDv1FallbackFactoryStartsBlockedAndIsSkipped) { + auto fdv2 = std::make_unique(); + auto fdv1 = std::make_unique(); + auto* fdv1_ptr = fdv1.get(); + std::vector> factories; + factories.push_back(std::move(fdv2)); + factories.push_back(std::move(fdv1)); + SourceManager mgr(std::move(factories)); + + EXPECT_EQ(1u, mgr.AvailableSynchronizerCount()); + mgr.NextSynchronizer(); + EXPECT_FALSE(mgr.IsCurrentSynchronizerFDv1Fallback()); + EXPECT_EQ(0, fdv1_ptr->build_count); +} + +TEST(SourceManagerTest, SwitchToFDv1FallbackBlocksFDv2AndUnblocksFDv1) { + auto fdv2 = std::make_unique(); + auto fdv1 = std::make_unique(); + auto* fdv1_ptr = fdv1.get(); + std::vector> factories; + factories.push_back(std::move(fdv2)); + factories.push_back(std::move(fdv1)); + SourceManager mgr(std::move(factories)); + + mgr.SwitchToFDv1Fallback(); + + EXPECT_EQ(1u, mgr.AvailableSynchronizerCount()); + auto sync = mgr.NextSynchronizer(); + ASSERT_NE(sync, nullptr); + EXPECT_EQ(1, fdv1_ptr->build_count); + EXPECT_TRUE(mgr.IsCurrentSynchronizerFDv1Fallback()); +} + +TEST(SourceManagerTest, SwitchToFDv1FallbackWithoutAdapterBlocksEverything) { + auto fdv2 = std::make_unique(); + std::vector> factories; + factories.push_back(std::move(fdv2)); + SourceManager mgr(std::move(factories)); + + mgr.SwitchToFDv1Fallback(); + + EXPECT_EQ(0u, mgr.AvailableSynchronizerCount()); + EXPECT_EQ(nullptr, mgr.NextSynchronizer()); +} + +TEST(SourceManagerTest, SwitchToFDv1FallbackUnblocksPreviouslyBlockedFDv2) { + auto fdv2 = std::make_unique(); + auto fdv1 = std::make_unique(); + auto* fdv1_ptr = fdv1.get(); + std::vector> factories; + factories.push_back(std::move(fdv2)); + factories.push_back(std::move(fdv1)); + SourceManager mgr(std::move(factories)); + + mgr.NextSynchronizer(); + mgr.BlockCurrentSynchronizer(); + mgr.SwitchToFDv1Fallback(); + + EXPECT_EQ(1u, mgr.AvailableSynchronizerCount()); + auto sync = mgr.NextSynchronizer(); + ASSERT_NE(sync, nullptr); + EXPECT_EQ(1, fdv1_ptr->build_count); + EXPECT_TRUE(mgr.IsCurrentSynchronizerFDv1Fallback()); +} From 77c972fe22a17b22c0252e619aeb2cbb7b78b84e Mon Sep 17 00:00:00 2001 From: Bee Klimt Date: Tue, 2 Jun 2026 13:29:57 -0700 Subject: [PATCH 02/17] chore: add orchestration logging for FDv2 data system --- .../data_systems/fdv2/fdv2_data_system.cpp | 68 +++++++++++-------- .../data_systems/fdv2/fdv2_data_system.hpp | 3 + 2 files changed, 44 insertions(+), 27 deletions(-) diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp index ba66bfe4f..83c4b874a 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp @@ -43,6 +43,7 @@ FDv2DataSystem::FDv2DataSystem( store_(), change_notifier_(store_, store_), initialize_called_(false), + last_logged_synchronizer_interrupted_(false), closed_(false), selector_(), initializer_index_(0), @@ -121,6 +122,9 @@ void FDv2DataSystem::RunNextInitializer() { } else { auto& factory = initializer_factories_[initializer_index_++]; active_initializer_ = factory->Build(); + LD_LOG(logger_, LogLevel::kInfo) + << Identity() << ": starting initializer " + << active_initializer_->Identity(); active_initializer_->Run().Then( [this](data_interfaces::FDv2SourceResult const& result) -> std::monostate { @@ -152,6 +156,8 @@ void FDv2DataSystem::OnInitializerResult( cs.change_set.selector.value.has_value(); ApplyChangeSet(std::move(cs.change_set)); if (has_selector) { + LD_LOG(logger_, LogLevel::kInfo) + << Identity() << ": initializer succeeded"; got_basis = true; } }, @@ -211,6 +217,10 @@ void FDv2DataSystem::StartSynchronizers() { } active_synchronizer_ = source_manager_.NextSynchronizer(); if (active_synchronizer_) { + LD_LOG(logger_, LogLevel::kInfo) + << Identity() << ": starting synchronizer " + << active_synchronizer_->Identity(); + last_logged_synchronizer_interrupted_.store(false); active_conditions_ = BuildActiveConditions(); } else { exhausted = true; @@ -320,33 +330,37 @@ void FDv2DataSystem::OnSynchronizerResult( bool got_shutdown = false; bool advance = false; - std::visit(overloaded{ - [&](Result::ChangeSet& cs) { - ApplyChangeSet(std::move(cs.change_set)); - }, - [&](Result::Shutdown&) { got_shutdown = true; }, - [&](Result::Interrupted const& iv) { - LD_LOG(logger_, LogLevel::kWarn) - << Identity() << ": synchronizer interrupted: " - << iv.error.Message(); - status_manager_->SetState( - DataSourceStatus::DataSourceState::kInterrupted, - iv.error.Kind(), iv.error.Message()); - }, - [&](Result::TerminalError const& te) { - LD_LOG(logger_, LogLevel::kWarn) - << Identity() << ": synchronizer terminal error: " - << te.error.Message(); - status_manager_->SetState( - DataSourceStatus::DataSourceState::kInterrupted, - te.error.Kind(), te.error.Message()); - advance = true; - }, - [&](Result::Goodbye const&) { - // The synchronizer handles this internally. - }, - }, - result.value); + std::visit( + overloaded{ + [&](Result::ChangeSet& cs) { + last_logged_synchronizer_interrupted_.store(false); + ApplyChangeSet(std::move(cs.change_set)); + }, + [&](Result::Shutdown&) { got_shutdown = true; }, + [&](Result::Interrupted const& iv) { + if (!last_logged_synchronizer_interrupted_.exchange(true)) { + LD_LOG(logger_, LogLevel::kInfo) + << Identity() + << ": synchronizer interrupted: " << iv.error.Message(); + } + status_manager_->SetState( + DataSourceStatus::DataSourceState::kInterrupted, + iv.error.Kind(), iv.error.Message()); + }, + [&](Result::TerminalError const& te) { + LD_LOG(logger_, LogLevel::kWarn) + << Identity() + << ": synchronizer terminal error: " << te.error.Message(); + status_manager_->SetState( + DataSourceStatus::DataSourceState::kInterrupted, + te.error.Kind(), te.error.Message()); + advance = true; + }, + [&](Result::Goodbye const&) { + // The synchronizer handles this internally. + }, + }, + result.value); { std::lock_guard lock(mutex_); diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.hpp b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.hpp index 7957de429..97e3b3c27 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.hpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.hpp @@ -283,6 +283,9 @@ class FDv2DataSystem final : public data_interfaces::IDataSystem { // Set by Initialize() to detect repeat or concurrent calls. std::atomic_bool initialize_called_; + // Suppresses consecutive "interrupted" logs from the active synchronizer. + std::atomic_bool last_logged_synchronizer_interrupted_; + // Orchestration state, guarded by mutex_. std::mutex mutex_; bool closed_; From 5a2a9bc5a0ba94f95756f92bd79503957e50a983 Mon Sep 17 00:00:00 2001 From: Bee Klimt Date: Wed, 3 Jun 2026 17:39:12 -0700 Subject: [PATCH 03/17] fix: stop emitting kOff status from FDv2DataSystem destructor --- .../data_systems/fdv2/fdv2_data_system.cpp | 1 - .../data_systems/fdv2/fdv2_data_system.hpp | 14 +++---- .../tests/fdv2_data_system_test.cpp | 39 ++++--------------- 3 files changed, 12 insertions(+), 42 deletions(-) diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp index 83c4b874a..695b08926 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp @@ -68,7 +68,6 @@ void FDv2DataSystem::Close() { if (active_conditions_) { active_conditions_->Close(); } - status_manager_->SetState(DataSourceStatus::DataSourceState::kOff); } std::shared_ptr FDv2DataSystem::GetFlag( diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.hpp b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.hpp index 97e3b3c27..2eb243140 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.hpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.hpp @@ -51,9 +51,8 @@ namespace launchdarkly::server_side::data_systems { * Destruction protocol: * * The destructor cancels in-flight orchestration (closes the active - * source, emits status kOff), but does NOT block to drain executor - * callbacks that may already be queued. Before destroying, the caller - * must ensure both of: + * source) but does NOT block to drain executor callbacks that may + * already be queued. Before destroying, the caller must ensure both of: * * 1. The executor that orchestration callbacks run on has been stopped * AND any thread running it has been joined. Otherwise a previously- @@ -120,8 +119,6 @@ namespace launchdarkly::server_side::data_systems { * v * [Done; final status preserved] * - * Calling the destructor at any time -> [Closed; status kOff]. - * * Status transitions: * * kInitializing (initial) -> kValid on first successful ChangeSet apply. @@ -130,11 +127,10 @@ namespace launchdarkly::server_side::data_systems { * the initializer phase if not yet Valid). * kOff if all initializers exhaust without data * and no synchronizers are configured. - * kValid -> kInterrupted on errors; kOff in destructor or - * when synchronizers cycle through and exhaust. + * kValid -> kInterrupted on errors; kOff when + * synchronizers cycle through and exhaust. * kInterrupted -> kValid on next successful ChangeSet apply; - * kOff in destructor or on synchronizer - * exhaustion. + * kOff on synchronizer exhaustion. * kOff -> terminal. */ class FDv2DataSystem final : public data_interfaces::IDataSystem { diff --git a/libs/server-sdk/tests/fdv2_data_system_test.cpp b/libs/server-sdk/tests/fdv2_data_system_test.cpp index 72ef65ff4..3170fcb7d 100644 --- a/libs/server-sdk/tests/fdv2_data_system_test.cpp +++ b/libs/server-sdk/tests/fdv2_data_system_test.cpp @@ -272,25 +272,6 @@ TEST(FDv2DataSystemTest, OfflineMode_NoFactories_StatusValid) { EXPECT_FALSE(ds.Initialized()); } -TEST(FDv2DataSystemTest, Destructor_TransitionsStatusToOff) { - auto logger = MakeNullLogger(); - boost::asio::io_context ioc; - data_components::DataSourceStatusManager status_manager; - - { - FDv2DataSystem ds({}, {}, /*fallback_condition_factory=*/nullptr, - /*recovery_condition_factory=*/nullptr, - ioc.get_executor(), &status_manager, logger); - ds.Initialize(); - ASSERT_EQ(status_manager.Status().State(), - DataSourceStatus::DataSourceState::kValid); - } - - // After ~FDv2DataSystem, status is Off. - EXPECT_EQ(status_manager.Status().State(), - DataSourceStatus::DataSourceState::kOff); -} - // ============================================================================ // Initializer phase // ============================================================================ @@ -1227,14 +1208,13 @@ TEST(FDv2DataSystemTest, InitializerFdv1FlagSwitchesToFdv1Adapter) { // ============================================================================ // // The destructor contract (fdv2_data_system.hpp) requires the destructor to -// cancel in-flight orchestration (close the active source, transition status -// to kOff) without firing any continuation against the destroyed object. The -// caller's responsibility is to ensure the executor is no longer running by -// the time destruction begins; the orchestrator's responsibility is to leave -// nothing dangling. These two tests pin that contract for both phases. +// cancel in-flight orchestration (close the active source) without firing +// any continuation against the destroyed object. The caller's responsibility +// is to ensure the executor is no longer running by the time destruction +// begins; the orchestrator's responsibility is to leave nothing dangling. +// These two tests pin that contract for both phases. -TEST(FDv2DataSystemTest, - Destructor_WithInFlightInitializer_ClosesSourceAndStatusOff) { +TEST(FDv2DataSystemTest, Destructor_WithInFlightInitializer_ClosesSource) { auto logger = MakeNullLogger(); boost::asio::io_context ioc; data_components::DataSourceStatusManager status_manager; @@ -1261,12 +1241,9 @@ TEST(FDv2DataSystemTest, // ~FDv2DataSystem ran with the initializer's Future still unresolved. EXPECT_TRUE(initializer_closed); - EXPECT_EQ(status_manager.Status().State(), - DataSourceStatus::DataSourceState::kOff); } -TEST(FDv2DataSystemTest, - Destructor_WithInFlightSynchronizer_ClosesSourceAndStatusOff) { +TEST(FDv2DataSystemTest, Destructor_WithInFlightSynchronizer_ClosesSource) { auto logger = MakeNullLogger(); boost::asio::io_context ioc; data_components::DataSourceStatusManager status_manager; @@ -1292,6 +1269,4 @@ TEST(FDv2DataSystemTest, } EXPECT_TRUE(synchronizer_closed); - EXPECT_EQ(status_manager.Status().State(), - DataSourceStatus::DataSourceState::kOff); } From 86b2e3d7244044142de698fc127fcac5a25aeea4 Mon Sep 17 00:00:00 2001 From: Bee Klimt Date: Thu, 28 May 2026 11:04:40 -0700 Subject: [PATCH 04/17] feat: add FDv1AdapterSynchronizer wrapping IDataSynchronizer as IFDv2Synchronizer --- libs/server-sdk/src/CMakeLists.txt | 2 + .../fdv2/fdv1_adapter_synchronizer.cpp | 187 +++++++++++++++++ .../fdv2/fdv1_adapter_synchronizer.hpp | 107 ++++++++++ .../tests/fdv1_adapter_synchronizer_test.cpp | 189 ++++++++++++++++++ 4 files changed, 485 insertions(+) create mode 100644 libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.cpp create mode 100644 libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.hpp create mode 100644 libs/server-sdk/tests/fdv1_adapter_synchronizer_test.cpp diff --git a/libs/server-sdk/src/CMakeLists.txt b/libs/server-sdk/src/CMakeLists.txt index 94e12f113..176c95421 100644 --- a/libs/server-sdk/src/CMakeLists.txt +++ b/libs/server-sdk/src/CMakeLists.txt @@ -76,6 +76,8 @@ target_sources(${LIBNAME} data_systems/fdv2/source_manager.cpp data_systems/fdv2/fdv2_data_system.hpp data_systems/fdv2/fdv2_data_system.cpp + data_systems/fdv2/fdv1_adapter_synchronizer.hpp + data_systems/fdv2/fdv1_adapter_synchronizer.cpp data_systems/background_sync/sources/streaming/streaming_data_source.hpp data_systems/background_sync/sources/streaming/streaming_data_source.cpp data_systems/background_sync/sources/streaming/event_handler.hpp diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.cpp b/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.cpp new file mode 100644 index 000000000..2dfd953cb --- /dev/null +++ b/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.cpp @@ -0,0 +1,187 @@ +#include "fdv1_adapter_synchronizer.hpp" + +#include + +namespace launchdarkly::server_side::data_systems { + +using data_interfaces::FDv2SourceResult; + +// ----- State ----- + +bool FDv1AdapterSynchronizer::State::TryStart() { + std::lock_guard lock(mutex_); + if (started_ || closed_) { + return false; + } + started_ = true; + return true; +} + +bool FDv1AdapterSynchronizer::State::MarkClosed() { + std::lock_guard lock(mutex_); + closed_ = true; + return started_; +} + +async::Future FDv1AdapterSynchronizer::State::GetNext() { + std::lock_guard lock(mutex_); + if (!result_queue_.empty()) { + auto result = std::move(result_queue_.front()); + result_queue_.pop_front(); + return async::MakeFuture(std::move(result)); + } + return pending_promise_.emplace().GetFuture(); +} + +void FDv1AdapterSynchronizer::State::ResolvePendingAsShutdown() { + std::optional> promise; + { + std::lock_guard lock(mutex_); + if (pending_promise_) { + promise = std::move(pending_promise_); + pending_promise_.reset(); + } + } + if (promise) { + promise->Resolve(FDv2SourceResult{FDv2SourceResult::Shutdown{}}); + } +} + +void FDv1AdapterSynchronizer::State::Notify(FDv2SourceResult result) { + std::optional> promise; + { + std::lock_guard lock(mutex_); + if (closed_) { + return; + } + if (pending_promise_) { + promise = std::move(pending_promise_); + pending_promise_.reset(); + } else { + result_queue_.push_back(std::move(result)); + return; + } + } + // Resolve outside the lock — Promise::Resolve may invoke inline + // continuations that could call back into Notify or GetNext. + promise->Resolve(std::move(result)); +} + +// ----- ConvertingDestination ----- + +FDv1AdapterSynchronizer::ConvertingDestination::ConvertingDestination( + std::weak_ptr state) + : state_(std::move(state)) {} + +void FDv1AdapterSynchronizer::ConvertingDestination::Init( + data_model::SDKDataSet data_set) { + auto state = state_.lock(); + if (!state) { + return; + } + data_interfaces::ChangeSetData changes; + changes.reserve(data_set.flags.size() + data_set.segments.size()); + for (auto& [key, flag] : data_set.flags) { + changes.push_back({key, std::move(flag)}); + } + for (auto& [key, segment] : data_set.segments) { + changes.push_back({key, std::move(segment)}); + } + state->Notify(FDv2SourceResult{FDv2SourceResult::ChangeSet{ + data_model::ChangeSet{ + data_model::ChangeSetType::kFull, std::move(changes), + data_model::Selector{}}}}); +} + +void FDv1AdapterSynchronizer::ConvertingDestination::Upsert( + std::string const& key, + data_model::FlagDescriptor flag) { + auto state = state_.lock(); + if (!state) { + return; + } + data_interfaces::ChangeSetData changes; + changes.push_back({key, std::move(flag)}); + state->Notify(FDv2SourceResult{FDv2SourceResult::ChangeSet{ + data_model::ChangeSet{ + data_model::ChangeSetType::kPartial, std::move(changes), + data_model::Selector{}}}}); +} + +void FDv1AdapterSynchronizer::ConvertingDestination::Upsert( + std::string const& key, + data_model::SegmentDescriptor segment) { + auto state = state_.lock(); + if (!state) { + return; + } + data_interfaces::ChangeSetData changes; + changes.push_back({key, std::move(segment)}); + state->Notify(FDv2SourceResult{FDv2SourceResult::ChangeSet{ + data_model::ChangeSet{ + data_model::ChangeSetType::kPartial, std::move(changes), + data_model::Selector{}}}}); +} + +std::string const& FDv1AdapterSynchronizer::ConvertingDestination::Identity() + const { + static std::string const identity = "FDv1 adapter destination"; + return identity; +} + +// ----- FDv1AdapterSynchronizer ----- + +FDv1AdapterSynchronizer::FDv1AdapterSynchronizer( + std::unique_ptr fdv1_source) + : state_(std::make_shared()), + destination_(std::make_unique(state_)), + fdv1_source_(std::move(fdv1_source)) {} + +FDv1AdapterSynchronizer::~FDv1AdapterSynchronizer() { + Close(); +} + +async::Future FDv1AdapterSynchronizer::Next( + data_model::Selector /*selector*/) { + auto closed = close_promise_.GetFuture(); + if (closed.IsFinished()) { + return async::MakeFuture( + FDv2SourceResult{FDv2SourceResult::Shutdown{}}); + } + if (state_->TryStart()) { + fdv1_source_->StartAsync(destination_.get(), + /*bootstrap_data=*/nullptr); + } + auto result_future = state_->GetNext(); + if (result_future.IsFinished()) { + return result_future; + } + return async::WhenAny(closed, result_future) + .Then( + [state = state_, result_future](std::size_t const& idx) mutable + -> async::Future { + if (idx == 0) { + state->ResolvePendingAsShutdown(); + return async::MakeFuture( + FDv2SourceResult{FDv2SourceResult::Shutdown{}}); + } + return result_future; + }, + async::kInlineExecutor); +} + +void FDv1AdapterSynchronizer::Close() { + if (!close_promise_.Resolve(std::monostate{})) { + return; + } + if (state_->MarkClosed()) { + fdv1_source_->ShutdownAsync([] {}); + } +} + +std::string const& FDv1AdapterSynchronizer::Identity() const { + static std::string const identity = "FDv1 fallback adapter"; + return identity; +} + +} // namespace launchdarkly::server_side::data_systems diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.hpp b/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.hpp new file mode 100644 index 000000000..7d2d10a3e --- /dev/null +++ b/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.hpp @@ -0,0 +1,107 @@ +#pragma once + +#include "../../data_interfaces/destination/idestination.hpp" +#include "../../data_interfaces/source/idata_synchronizer.hpp" +#include "../../data_interfaces/source/ifdv2_synchronizer.hpp" + +#include + +#include +#include +#include +#include +#include +#include + +namespace launchdarkly::server_side::data_systems { + +/** + * Adapts an FDv1 IDataSynchronizer to the IFDv2Synchronizer interface. + * + * FDv1 Init/Upsert callbacks delivered through an internal IDestination are + * translated into FDv2SourceResult::ChangeSet results, with empty selectors + * and fdv1_fallback = false (the directive does not re-fire from FDv1 data). + * + * Threading: Next() and Close() may be called from any thread; only one + * Next() may be outstanding at a time. The adapter blocks in its destructor + * waiting for the FDv1 source's ShutdownAsync completion, so no callbacks + * are in flight when the wrapped source is destroyed. + */ +class FDv1AdapterSynchronizer final + : public data_interfaces::IFDv2Synchronizer { + public: + explicit FDv1AdapterSynchronizer( + std::unique_ptr fdv1_source); + + ~FDv1AdapterSynchronizer() override; + + async::Future Next( + data_model::Selector selector) override; + void Close() override; + [[nodiscard]] std::string const& Identity() const override; + + private: + /** + * Holds the lifecycle, result queue, and pending Next() promise; shared + * with the FDv1 source's IDestination via the inner ConvertingDestination. + * All methods are thread-safe. + */ + class State { + public: + // Returns true if this call transitioned Initial → Started; false if + // already started or already closed. Used to gate the one-time + // StartAsync call on the wrapped FDv1 source. + bool TryStart(); + + // Marks the state closed and returns whether the source was started + // before the transition (so the caller knows whether ShutdownAsync + // needs to be called). + bool MarkClosed(); + + async::Future GetNext(); + + // Resolves any pending Next() promise with Shutdown and clears it. + // Called on the close path so the abandoned promise doesn't leave + // potential continuations dangling. + void ResolvePendingAsShutdown(); + + void Notify(data_interfaces::FDv2SourceResult result); + + private: + // Protected by mutex_. + mutable std::mutex mutex_; + bool started_ = false; + bool closed_ = false; + std::optional> + pending_promise_; + std::deque result_queue_; + }; + + /** + * Translates FDv1 IDestination callbacks into FDv2 results queued on + * State. Thread-safe (delegates to State). + */ + class ConvertingDestination final : public data_interfaces::IDestination { + public: + explicit ConvertingDestination(std::weak_ptr state); + void Init(data_model::SDKDataSet data_set) override; + void Upsert(std::string const& key, + data_model::FlagDescriptor flag) override; + void Upsert(std::string const& key, + data_model::SegmentDescriptor segment) override; + [[nodiscard]] std::string const& Identity() const override; + + private: + std::weak_ptr state_; + }; + + // const after construction. + std::shared_ptr const state_; + std::unique_ptr const destination_; + std::unique_ptr const fdv1_source_; + + // Thread-safe primitive. + async::Promise close_promise_; +}; + +} // namespace launchdarkly::server_side::data_systems diff --git a/libs/server-sdk/tests/fdv1_adapter_synchronizer_test.cpp b/libs/server-sdk/tests/fdv1_adapter_synchronizer_test.cpp new file mode 100644 index 000000000..77058f6bc --- /dev/null +++ b/libs/server-sdk/tests/fdv1_adapter_synchronizer_test.cpp @@ -0,0 +1,189 @@ +#include + +#include + +#include +#include +#include +#include + +using namespace launchdarkly; +using namespace launchdarkly::server_side::data_interfaces; +using namespace launchdarkly::server_side::data_systems; +using namespace std::chrono_literals; + +namespace { + +// Mock FDv1 source: records StartAsync and ShutdownAsync calls and exposes +// the IDestination it was given so the test can drive Init/Upsert. +class MockFDv1Source final : public IDataSynchronizer { + public: + void StartAsync(IDestination* destination, + data_model::SDKDataSet const* bootstrap) override { + ++start_count; + destination_ = destination; + bootstrap_was_null = (bootstrap == nullptr); + } + + void ShutdownAsync(std::function completion) override { + ++shutdown_count; + if (completion) { + completion(); + } + } + + std::string const& Identity() const override { + static std::string const id = "mock fdv1"; + return id; + } + + IDestination* destination_ = nullptr; + int start_count = 0; + int shutdown_count = 0; + bool bootstrap_was_null = false; +}; + +} // namespace + +TEST(FDv1AdapterSynchronizerTest, FirstNextStartsFDv1Source) { + auto source = std::make_unique(); + auto* source_ptr = source.get(); + FDv1AdapterSynchronizer adapter(std::move(source)); + + auto future = adapter.Next(data_model::Selector{}); + + EXPECT_EQ(1, source_ptr->start_count); + EXPECT_TRUE(source_ptr->bootstrap_was_null); + EXPECT_FALSE(future.IsFinished()); +} + +TEST(FDv1AdapterSynchronizerTest, SecondNextDoesNotRestartSource) { + auto source = std::make_unique(); + auto* source_ptr = source.get(); + FDv1AdapterSynchronizer adapter(std::move(source)); + + auto first = adapter.Next(data_model::Selector{}); + source_ptr->destination_->Init(data_model::SDKDataSet{}); + auto result = first.WaitForResult(1s); + ASSERT_TRUE(result.has_value()); + adapter.Next(data_model::Selector{}); + + EXPECT_EQ(1, source_ptr->start_count); +} + +TEST(FDv1AdapterSynchronizerTest, FDv1InitProducesFullChangeSet) { + auto source = std::make_unique(); + auto* source_ptr = source.get(); + FDv1AdapterSynchronizer adapter(std::move(source)); + + auto future = adapter.Next(data_model::Selector{}); + + data_model::SDKDataSet data_set; + data_model::Flag flag; + flag.key = "flagA"; + flag.version = 1; + data_set.flags.emplace("flagA", data_model::FlagDescriptor(flag)); + source_ptr->destination_->Init(std::move(data_set)); + + auto result = future.WaitForResult(1s); + ASSERT_TRUE(result.has_value()); + auto* change_set = std::get_if(&result->value); + ASSERT_NE(change_set, nullptr); + EXPECT_EQ(data_model::ChangeSetType::kFull, change_set->change_set.type); + ASSERT_EQ(1u, change_set->change_set.data.size()); + EXPECT_EQ("flagA", change_set->change_set.data[0].key); + EXPECT_FALSE(change_set->change_set.selector.value.has_value()); + EXPECT_FALSE(result->fdv1_fallback); +} + +TEST(FDv1AdapterSynchronizerTest, FDv1UpsertProducesPartialChangeSet) { + auto source = std::make_unique(); + auto* source_ptr = source.get(); + FDv1AdapterSynchronizer adapter(std::move(source)); + + // Flag upsert. + auto flag_future = adapter.Next(data_model::Selector{}); + data_model::Flag flag; + flag.key = "flagA"; + flag.version = 2; + source_ptr->destination_->Upsert("flagA", data_model::FlagDescriptor(flag)); + + auto flag_result = flag_future.WaitForResult(1s); + ASSERT_TRUE(flag_result.has_value()); + auto* flag_change_set = + std::get_if(&flag_result->value); + ASSERT_NE(flag_change_set, nullptr); + EXPECT_EQ(data_model::ChangeSetType::kPartial, + flag_change_set->change_set.type); + ASSERT_EQ(1u, flag_change_set->change_set.data.size()); + EXPECT_EQ("flagA", flag_change_set->change_set.data[0].key); + + // Segment upsert. + auto seg_future = adapter.Next(data_model::Selector{}); + data_model::Segment seg; + seg.key = "segA"; + seg.version = 3; + source_ptr->destination_->Upsert("segA", + data_model::SegmentDescriptor(seg)); + + auto seg_result = seg_future.WaitForResult(1s); + ASSERT_TRUE(seg_result.has_value()); + auto* seg_change_set = + std::get_if(&seg_result->value); + ASSERT_NE(seg_change_set, nullptr); + EXPECT_EQ(data_model::ChangeSetType::kPartial, + seg_change_set->change_set.type); + ASSERT_EQ(1u, seg_change_set->change_set.data.size()); + EXPECT_EQ("segA", seg_change_set->change_set.data[0].key); +} + +TEST(FDv1AdapterSynchronizerTest, ClosePendingNextReturnsShutdown) { + auto source = std::make_unique(); + FDv1AdapterSynchronizer adapter(std::move(source)); + + auto future = adapter.Next(data_model::Selector{}); + EXPECT_FALSE(future.IsFinished()); + + adapter.Close(); + + auto result = future.WaitForResult(1s); + ASSERT_TRUE(result.has_value()); + EXPECT_TRUE( + std::holds_alternative(result->value)); +} + +TEST(FDv1AdapterSynchronizerTest, CloseShutsDownStartedFDv1Source) { + auto source = std::make_unique(); + auto* source_ptr = source.get(); + FDv1AdapterSynchronizer adapter(std::move(source)); + + adapter.Next(data_model::Selector{}); + adapter.Close(); + + EXPECT_EQ(1, source_ptr->shutdown_count); +} + +TEST(FDv1AdapterSynchronizerTest, CloseWithoutStartDoesNotShutDownFDv1Source) { + auto source = std::make_unique(); + auto* source_ptr = source.get(); + FDv1AdapterSynchronizer adapter(std::move(source)); + + // No Next() call — FDv1 source was never started. + adapter.Close(); + + EXPECT_EQ(0, source_ptr->start_count); + EXPECT_EQ(0, source_ptr->shutdown_count); +} + +TEST(FDv1AdapterSynchronizerTest, NextAfterCloseReturnsShutdown) { + auto source = std::make_unique(); + FDv1AdapterSynchronizer adapter(std::move(source)); + + adapter.Close(); + auto future = adapter.Next(data_model::Selector{}); + + auto result = future.WaitForResult(1s); + ASSERT_TRUE(result.has_value()); + EXPECT_TRUE( + std::holds_alternative(result->value)); +} From f99f1ad29d9ec42d35ebd6ae438f95d058558347 Mon Sep 17 00:00:00 2001 From: Bee Klimt Date: Sun, 7 Jun 2026 21:55:21 -0700 Subject: [PATCH 05/17] chore: distinguish engaged vs. unconfigured FDv1 fallback in logs --- .../data_systems/fdv2/fdv2_data_system.cpp | 22 +++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-) diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp index 695b08926..a0425aff8 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp @@ -191,9 +191,16 @@ void FDv2DataSystem::OnInitializerResult( return; } if (result.fdv1_fallback) { - LD_LOG(logger_, LogLevel::kInfo) - << Identity() << ": FDv1 fallback engaged"; source_manager_.SwitchToFDv1Fallback(); + if (source_manager_.AvailableSynchronizerCount() > 0) { + LD_LOG(logger_, LogLevel::kInfo) + << Identity() << ": FDv1 fallback engaged"; + } else { + LD_LOG(logger_, LogLevel::kWarn) + << Identity() + << ": FDv1 fallback directive received; no FDv1 " + "fallback synchronizer configured"; + } got_basis = true; } } @@ -369,9 +376,16 @@ void FDv2DataSystem::OnSynchronizerResult( return; } if (result.fdv1_fallback) { - LD_LOG(logger_, LogLevel::kInfo) - << Identity() << ": FDv1 fallback engaged"; source_manager_.SwitchToFDv1Fallback(); + if (source_manager_.AvailableSynchronizerCount() > 0) { + LD_LOG(logger_, LogLevel::kInfo) + << Identity() << ": FDv1 fallback engaged"; + } else { + LD_LOG(logger_, LogLevel::kWarn) + << Identity() + << ": FDv1 fallback directive received; no FDv1 " + "fallback synchronizer configured"; + } active_synchronizer_.reset(); active_conditions_.reset(); advance = true; From 82d2730720700f8b66671a9bb006ec27b2cc26d4 Mon Sep 17 00:00:00 2001 From: Bee Klimt Date: Sun, 7 Jun 2026 22:03:36 -0700 Subject: [PATCH 06/17] fix: ignore FDv1 fallback directive when FDv1 source is active --- .../data_systems/fdv2/fdv2_data_system.cpp | 3 +- .../tests/fdv2_data_system_test.cpp | 51 +++++++++++++++++++ 2 files changed, 53 insertions(+), 1 deletion(-) diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp index a0425aff8..58d5b6f3b 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp @@ -375,7 +375,8 @@ void FDv2DataSystem::OnSynchronizerResult( active_conditions_.reset(); return; } - if (result.fdv1_fallback) { + if (result.fdv1_fallback && + !source_manager_.IsCurrentSynchronizerFDv1Fallback()) { source_manager_.SwitchToFDv1Fallback(); if (source_manager_.AvailableSynchronizerCount() > 0) { LD_LOG(logger_, LogLevel::kInfo) diff --git a/libs/server-sdk/tests/fdv2_data_system_test.cpp b/libs/server-sdk/tests/fdv2_data_system_test.cpp index 3170fcb7d..486225592 100644 --- a/libs/server-sdk/tests/fdv2_data_system_test.cpp +++ b/libs/server-sdk/tests/fdv2_data_system_test.cpp @@ -1203,6 +1203,57 @@ TEST(FDv2DataSystemTest, InitializerFdv1FlagSwitchesToFdv1Adapter) { EXPECT_EQ(1, fdv1_factory_ptr->build_count_); } +TEST(FDv2DataSystemTest, FDv1SourceSelfDirectiveDoesNotRebuildFDv1) { + auto logger = MakeNullLogger(); + boost::asio::io_context ioc; + data_components::DataSourceStatusManager status_manager; + + // FDv2 source emits a ChangeSet with the directive, switching to the + // FDv1 fallback. + auto fdv2_sync = + std::make_unique(std::vector{[]() { + FDv2SourceResult r{FDv2SourceResult::ChangeSet{ + data_model::ChangeSet{ + data_model::ChangeSetType::kNone, + {}, + data_model::Selector{}}}}; + r.fdv1_fallback = true; + return r; + }()}); + auto fdv2_factory = + std::make_unique(std::move(fdv2_sync)); + + // FDv1 source then emits a result also carrying the directive. Once + // FDv1 is active, the directive is silently ignored and the source is + // not rebuilt. + auto fdv1_sync = + std::make_unique(std::vector{[]() { + FDv2SourceResult r{ + FDv2SourceResult::Interrupted{FDv2SourceResult::ErrorInfo{ + FDv2SourceResult::ErrorInfo::ErrorKind::kErrorResponse, + /*status_code=*/418, "self-trigger", + std::chrono::system_clock::now()}}}; + r.fdv1_fallback = true; + return r; + }()}); + auto fdv1_factory = + std::make_unique(std::move(fdv1_sync)); + auto* fdv1_factory_ptr = fdv1_factory.get(); + + std::vector> synchronizers; + synchronizers.push_back(std::move(fdv2_factory)); + synchronizers.push_back(std::move(fdv1_factory)); + + FDv2DataSystem ds({}, std::move(synchronizers), + /*fallback_condition_factory=*/nullptr, + /*recovery_condition_factory=*/nullptr, + ioc.get_executor(), &status_manager, logger); + ds.Initialize(); + ioc.run(); + + EXPECT_EQ(1, fdv1_factory_ptr->build_count_); +} + // ============================================================================ // Destruction protocol: in-flight orchestration // ============================================================================ From c164913240f1a91b5ed2ce838d9ac768596330ca Mon Sep 17 00:00:00 2001 From: Bee Klimt Date: Mon, 8 Jun 2026 09:55:25 -0700 Subject: [PATCH 07/17] test: cover initializer ChangeSet+directive basis preservation --- .../tests/fdv2_data_system_test.cpp | 61 +++++++++++++++++++ 1 file changed, 61 insertions(+) diff --git a/libs/server-sdk/tests/fdv2_data_system_test.cpp b/libs/server-sdk/tests/fdv2_data_system_test.cpp index 486225592..12d9150eb 100644 --- a/libs/server-sdk/tests/fdv2_data_system_test.cpp +++ b/libs/server-sdk/tests/fdv2_data_system_test.cpp @@ -1203,6 +1203,67 @@ TEST(FDv2DataSystemTest, InitializerFdv1FlagSwitchesToFdv1Adapter) { EXPECT_EQ(1, fdv1_factory_ptr->build_count_); } +TEST(FDv2DataSystemTest, + InitializerChangeSetWithDirectiveAppliesBasisThenSwitches) { + auto logger = MakeNullLogger(); + boost::asio::io_context ioc; + data_components::DataSourceStatusManager status_manager; + + // Initializer returns a Full changeset carrying a flag AND the directive. + // The basis must be applied to the store before the orchestrator + // transitions to the FDv1 fallback. + data_model::Flag flag_a; + flag_a.key = "flagA"; + flag_a.version = 1; + + FDv2SourceResult init_result = MakeFullChangeSetResult( + ChangeSetData{ + ItemChange{"flagA", data_model::FlagDescriptor(flag_a)}, + }, + MakeSelector(1, "state-1")); + init_result.fdv1_fallback = true; + + auto initializer = + std::make_unique(std::move(init_result)); + + std::vector> initializers; + initializers.push_back( + std::make_unique(std::move(initializer))); + + auto fdv2_sync = + std::make_unique(std::vector{}); + auto fdv2_factory = + std::make_unique(std::move(fdv2_sync)); + auto* fdv2_factory_ptr = fdv2_factory.get(); + + auto fdv1_sync = + std::make_unique(std::vector{}); + auto fdv1_factory = + std::make_unique(std::move(fdv1_sync)); + auto* fdv1_factory_ptr = fdv1_factory.get(); + + std::vector> synchronizers; + synchronizers.push_back(std::move(fdv2_factory)); + synchronizers.push_back(std::move(fdv1_factory)); + + FDv2DataSystem ds(std::move(initializers), std::move(synchronizers), + /*fallback_condition_factory=*/nullptr, + /*recovery_condition_factory=*/nullptr, + ioc.get_executor(), &status_manager, logger); + ds.Initialize(); + ioc.run(); + + // Basis applied before the switch. + EXPECT_TRUE(ds.Initialized()); + auto fetched = ds.GetFlag("flagA"); + ASSERT_TRUE(fetched); + EXPECT_EQ(1u, fetched->version); + + // FDv2 synchronizer skipped; FDv1 adapter built and ran. + EXPECT_EQ(0, fdv2_factory_ptr->build_count_); + EXPECT_EQ(1, fdv1_factory_ptr->build_count_); +} + TEST(FDv2DataSystemTest, FDv1SourceSelfDirectiveDoesNotRebuildFDv1) { auto logger = MakeNullLogger(); boost::asio::io_context ioc; From 44f47f4dac873ca1d2faf8b6c0d00960bfefbb71 Mon Sep 17 00:00:00 2001 From: Bee Klimt Date: Mon, 8 Jun 2026 14:02:17 -0700 Subject: [PATCH 08/17] feat: parse X-LD-FD-Fallback-TTL header into FDv2SourceResult --- .../source/fdv2_source_result.hpp | 44 +++++++++++++- .../data_systems/fdv2/fdv2_polling_impl.cpp | 21 +++++-- .../fdv2/streaming_synchronizer.cpp | 17 +++++- .../fdv2/streaming_synchronizer.hpp | 3 +- .../tests/fdv2_data_system_test.cpp | 12 ++-- .../tests/fdv2_polling_impl_test.cpp | 23 ++++++++ .../fdv2_streaming_synchronizer_test.cpp | 57 +++++++++++++++++++ 7 files changed, 161 insertions(+), 16 deletions(-) diff --git a/libs/server-sdk/src/data_interfaces/source/fdv2_source_result.hpp b/libs/server-sdk/src/data_interfaces/source/fdv2_source_result.hpp index 73329f348..53a0cd442 100644 --- a/libs/server-sdk/src/data_interfaces/source/fdv2_source_result.hpp +++ b/libs/server-sdk/src/data_interfaces/source/fdv2_source_result.hpp @@ -5,12 +5,51 @@ #include #include +#include +#include +#include #include #include +#include +#include #include namespace launchdarkly::server_side::data_interfaces { +/** + * Server-directed instruction to fall back to FDv1, carried alongside any + * FDv2 source result whose underlying transport observed it (e.g. an + * X-LD-FD-Fallback: true response header). + */ +struct FDv1FallbackDirective { + /** Default TTL used when the directive carries no TTL of its own. */ + static constexpr std::chrono::seconds kDefaultTtl = std::chrono::hours(1); + + /** + * Parse the value of an X-LD-FD-Fallback-TTL header (or equivalent + * protocolFallbackTTL field from a goodbye message). Returns + * std::nullopt if the value is malformed. + */ + static std::optional ParseTtl( + std::string_view value) { + std::uint64_t seconds = 0; + auto const* begin = value.data(); + auto const* end = begin + value.size(); + auto const [ptr, ec] = std::from_chars(begin, end, seconds); + if (ec != std::errc{} || ptr != end) { + return std::nullopt; + } + return std::chrono::seconds(seconds); + } + + /** + * How long to stay on FDv1 before attempting to recover to FDv2. + * A value of 0 seconds means the SDK should remain on FDv1 + * indefinitely. + */ + std::chrono::seconds ttl = kDefaultTtl; +}; + /** * Result returned by IFDv2Initializer::Run and IFDv2Synchronizer::Next. */ @@ -56,10 +95,9 @@ struct FDv2SourceResult { Value value; /** - * If true, the server signaled (via the X-LD-FD-Fallback response header) - * that the client should fall back to FDv1. + * Set if the underlying transport observed an FDv1 fallback directive. */ - bool fdv1_fallback = false; + std::optional fdv1_fallback; }; } // namespace launchdarkly::server_side::data_interfaces diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv2_polling_impl.cpp b/libs/server-sdk/src/data_systems/fdv2/fdv2_polling_impl.cpp index 1178aff46..7d18deea5 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv2_polling_impl.cpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv2_polling_impl.cpp @@ -13,6 +13,7 @@ namespace launchdarkly::server_side::data_systems { static char const* const kFDv1FallbackHeader = "X-LD-FD-Fallback"; +static char const* const kFDv1FallbackTtlHeader = "X-LD-FD-Fallback-TTL"; static char const* const kErrorParsingBody = "Could not parse FDv2 polling response"; @@ -34,10 +35,22 @@ static ErrorInfo MakeError(ErrorKind kind, std::chrono::system_clock::now()}; } -static bool ReadFDv1FallbackDirective( - network::HttpResult::HeadersType const& headers) { +static std::optional +ReadFDv1FallbackDirective(network::HttpResult::HeadersType const& headers) { auto const it = headers.find(kFDv1FallbackHeader); - return it != headers.end() && boost::iequals(it->second, "true"); + if (it == headers.end() || !boost::iequals(it->second, "true")) { + return std::nullopt; + } + data_interfaces::FDv1FallbackDirective directive; + auto const ttl_it = headers.find(kFDv1FallbackTtlHeader); + if (ttl_it != headers.end()) { + auto const ttl = + data_interfaces::FDv1FallbackDirective::ParseTtl(ttl_it->second); + if (ttl) { + directive.ttl = *ttl; + } + } + return directive; } network::HttpRequest MakeFDv2PollRequest( @@ -183,7 +196,7 @@ data_interfaces::FDv2SourceResult HandleFDv2PollResponse( MakeError(ErrorKind::kNetworkError, 0, std::move(error_msg))}}; } - bool const fdv1_fallback = ReadFDv1FallbackDirective(res.Headers()); + auto fdv1_fallback = ReadFDv1FallbackDirective(res.Headers()); if (res.Status() == 304) { return FDv2SourceResult{ diff --git a/libs/server-sdk/src/data_systems/fdv2/streaming_synchronizer.cpp b/libs/server-sdk/src/data_systems/fdv2/streaming_synchronizer.cpp index c43483fc3..868725630 100644 --- a/libs/server-sdk/src/data_systems/fdv2/streaming_synchronizer.cpp +++ b/libs/server-sdk/src/data_systems/fdv2/streaming_synchronizer.cpp @@ -187,8 +187,21 @@ void FDv2StreamingSynchronizer::State::OnConnect(HttpRequest* req) { void FDv2StreamingSynchronizer::State::OnResponse( HttpResponseHeader const& headers) { auto const it = headers.find("X-LD-FD-Fallback"); - bool const directive = - it != headers.end() && boost::iequals(it->value(), "true"); + if (it == headers.end() || !boost::iequals(it->value(), "true")) { + std::lock_guard lock(mutex_); + latest_fdv1_fallback_.reset(); + return; + } + data_interfaces::FDv1FallbackDirective directive; + auto const ttl_it = headers.find("X-LD-FD-Fallback-TTL"); + if (ttl_it != headers.end()) { + auto const value = ttl_it->value(); + auto const ttl = data_interfaces::FDv1FallbackDirective::ParseTtl( + std::string_view{value.data(), value.size()}); + if (ttl) { + directive.ttl = *ttl; + } + } std::lock_guard lock(mutex_); latest_fdv1_fallback_ = directive; } diff --git a/libs/server-sdk/src/data_systems/fdv2/streaming_synchronizer.hpp b/libs/server-sdk/src/data_systems/fdv2/streaming_synchronizer.hpp index 1abed1f64..4e297212c 100644 --- a/libs/server-sdk/src/data_systems/fdv2/streaming_synchronizer.hpp +++ b/libs/server-sdk/src/data_systems/fdv2/streaming_synchronizer.hpp @@ -147,7 +147,8 @@ class FDv2StreamingSynchronizer final bool started_ = false; bool closed_ = false; // FDv1 fallback directive from the most recent SSE response. - bool latest_fdv1_fallback_ = false; + std::optional + latest_fdv1_fallback_; data_model::Selector latest_selector_; std::optional base_url_; std::shared_ptr sse_client_; diff --git a/libs/server-sdk/tests/fdv2_data_system_test.cpp b/libs/server-sdk/tests/fdv2_data_system_test.cpp index 12d9150eb..96e2fc33d 100644 --- a/libs/server-sdk/tests/fdv2_data_system_test.cpp +++ b/libs/server-sdk/tests/fdv2_data_system_test.cpp @@ -1097,7 +1097,7 @@ TEST(FDv2DataSystemTest, SynchronizerFdv1FlagSwitchesToFdv1Adapter) { data_model::ChangeSetType::kNone, {}, data_model::Selector{}}}}; - r.fdv1_fallback = true; + r.fdv1_fallback = data_interfaces::FDv1FallbackDirective{}; return r; }()}); auto fdv2_factory = @@ -1136,7 +1136,7 @@ TEST(FDv2DataSystemTest, SynchronizerFdv1FlagWithoutAdapterTransitionsOff) { FDv2SourceResult::ErrorInfo::ErrorKind::kErrorResponse, /*status_code=*/418, "directive", std::chrono::system_clock::now()}}}; - r.fdv1_fallback = true; + r.fdv1_fallback = data_interfaces::FDv1FallbackDirective{}; return r; }()}); auto fdv2_factory = @@ -1167,7 +1167,7 @@ TEST(FDv2DataSystemTest, InitializerFdv1FlagSwitchesToFdv1Adapter) { FDv2SourceResult::ErrorInfo::ErrorKind::kErrorResponse, /*status_code=*/418, "directive", std::chrono::system_clock::now()}}}; - init_result.fdv1_fallback = true; + init_result.fdv1_fallback = data_interfaces::FDv1FallbackDirective{}; auto initializer = std::make_unique(std::move(init_result)); @@ -1221,7 +1221,7 @@ TEST(FDv2DataSystemTest, ItemChange{"flagA", data_model::FlagDescriptor(flag_a)}, }, MakeSelector(1, "state-1")); - init_result.fdv1_fallback = true; + init_result.fdv1_fallback = data_interfaces::FDv1FallbackDirective{}; auto initializer = std::make_unique(std::move(init_result)); @@ -1278,7 +1278,7 @@ TEST(FDv2DataSystemTest, FDv1SourceSelfDirectiveDoesNotRebuildFDv1) { data_model::ChangeSetType::kNone, {}, data_model::Selector{}}}}; - r.fdv1_fallback = true; + r.fdv1_fallback = data_interfaces::FDv1FallbackDirective{}; return r; }()}); auto fdv2_factory = @@ -1294,7 +1294,7 @@ TEST(FDv2DataSystemTest, FDv1SourceSelfDirectiveDoesNotRebuildFDv1) { FDv2SourceResult::ErrorInfo::ErrorKind::kErrorResponse, /*status_code=*/418, "self-trigger", std::chrono::system_clock::now()}}}; - r.fdv1_fallback = true; + r.fdv1_fallback = data_interfaces::FDv1FallbackDirective{}; return r; }()}); auto fdv1_factory = diff --git a/libs/server-sdk/tests/fdv2_polling_impl_test.cpp b/libs/server-sdk/tests/fdv2_polling_impl_test.cpp index c9ed53da5..531a41aa6 100644 --- a/libs/server-sdk/tests/fdv2_polling_impl_test.cpp +++ b/libs/server-sdk/tests/fdv2_polling_impl_test.cpp @@ -98,6 +98,29 @@ TEST(HandleFDv2PollResponseTest, HeaderValueOtherThanTrueDoesNotSetFlag) { EXPECT_FALSE(result.fdv1_fallback); } +TEST(HandleFDv2PollResponseTest, DirectiveWithoutTtlHeaderUsesDefault) { + auto result = + HandleResponse(304, std::nullopt, {{"X-LD-FD-Fallback", "true"}}); + ASSERT_TRUE(result.fdv1_fallback); + EXPECT_EQ(FDv1FallbackDirective::kDefaultTtl, result.fdv1_fallback->ttl); +} + +TEST(HandleFDv2PollResponseTest, DirectiveWithTtlHeaderParsesValue) { + auto result = HandleResponse( + 304, std::nullopt, + {{"X-LD-FD-Fallback", "true"}, {"X-LD-FD-Fallback-TTL", "60"}}); + ASSERT_TRUE(result.fdv1_fallback); + EXPECT_EQ(std::chrono::seconds{60}, result.fdv1_fallback->ttl); +} + +TEST(HandleFDv2PollResponseTest, DirectiveWithMalformedTtlFallsBackToDefault) { + auto result = HandleResponse(304, std::nullopt, + {{"X-LD-FD-Fallback", "true"}, + {"X-LD-FD-Fallback-TTL", "not-a-number"}}); + ASSERT_TRUE(result.fdv1_fallback); + EXPECT_EQ(FDv1FallbackDirective::kDefaultTtl, result.fdv1_fallback->ttl); +} + TEST(HandleFDv2PollResponseTest, NetworkErrorDoesNotSetFlag) { auto logger = MakeNullLogger(); FDv2ProtocolHandler handler; diff --git a/libs/server-sdk/tests/fdv2_streaming_synchronizer_test.cpp b/libs/server-sdk/tests/fdv2_streaming_synchronizer_test.cpp index 68687adb5..be4a1fe3e 100644 --- a/libs/server-sdk/tests/fdv2_streaming_synchronizer_test.cpp +++ b/libs/server-sdk/tests/fdv2_streaming_synchronizer_test.cpp @@ -854,3 +854,60 @@ TEST(FDv2StreamingSynchronizerTest, ErrorAfterDirectiveCarriesFlag) { std::holds_alternative(result->value)); EXPECT_TRUE(result->fdv1_fallback); } + +TEST(FDv2StreamingSynchronizerTest, DirectiveWithTtlHeaderParsesValue) { + auto logger = MakeNullLogger(); + IoContextRunner runner; + + FDv2StreamingSynchronizer synchronizer( + runner.context().get_executor(), logger, + MakeEndpoints("http://localhost"), MakeHttpProperties(), std::nullopt, + 1s); + FDv2StreamingSynchronizerTestPeer::MarkStarted(synchronizer); + + // Server sends the directive with an explicit TTL. + boost::beast::http::response_header<> headers; + headers.result(200); + headers.set("X-LD-FD-Fallback", "true"); + headers.set("X-LD-FD-Fallback-TTL", "60"); + FDv2StreamingSynchronizerTestPeer::OnResponse(synchronizer, headers); + + // Drive the source to surface the directive on its next result. + FDv2StreamingSynchronizerTestPeer::OnError( + synchronizer, + sse::Error{sse::errors::ReadTimeout{std::chrono::milliseconds(0)}}); + auto result = synchronizer.Next(data_model::Selector{}).WaitForResult(2s); + + // The parsed TTL is propagated on the result. + ASSERT_TRUE(result.has_value()); + ASSERT_TRUE(result->fdv1_fallback); + EXPECT_EQ(std::chrono::seconds{60}, result->fdv1_fallback->ttl); +} + +TEST(FDv2StreamingSynchronizerTest, DirectiveWithoutTtlHeaderUsesDefault) { + auto logger = MakeNullLogger(); + IoContextRunner runner; + + FDv2StreamingSynchronizer synchronizer( + runner.context().get_executor(), logger, + MakeEndpoints("http://localhost"), MakeHttpProperties(), std::nullopt, + 1s); + FDv2StreamingSynchronizerTestPeer::MarkStarted(synchronizer); + + // Server sends the directive with no TTL header. + boost::beast::http::response_header<> headers; + headers.result(200); + headers.set("X-LD-FD-Fallback", "true"); + FDv2StreamingSynchronizerTestPeer::OnResponse(synchronizer, headers); + + // Drive the source to surface the directive on its next result. + FDv2StreamingSynchronizerTestPeer::OnError( + synchronizer, + sse::Error{sse::errors::ReadTimeout{std::chrono::milliseconds(0)}}); + auto result = synchronizer.Next(data_model::Selector{}).WaitForResult(2s); + + // The result carries the default TTL. + ASSERT_TRUE(result.has_value()); + ASSERT_TRUE(result->fdv1_fallback); + EXPECT_EQ(FDv1FallbackDirective::kDefaultTtl, result->fdv1_fallback->ttl); +} From 6ca1a4973ee021120e91754bd4ef0bde2a8c6ebf Mon Sep 17 00:00:00 2001 From: Bee Klimt Date: Mon, 8 Jun 2026 14:33:05 -0700 Subject: [PATCH 09/17] feat: parse protocolFallbackTTL and retryAfter from goodbye --- .../serialization/json_fdv2_events.hpp | 4 ++++ .../src/serialization/json_fdv2_events.cpp | 3 +++ .../tests/fdv2_serialization_test.cpp | 20 +++++++++++++++++++ .../data_systems/fdv2/fdv2_polling_impl.cpp | 13 ++++++++++-- .../fdv2/streaming_synchronizer.cpp | 16 +++++++++++++-- 5 files changed, 52 insertions(+), 4 deletions(-) diff --git a/libs/internal/include/launchdarkly/serialization/json_fdv2_events.hpp b/libs/internal/include/launchdarkly/serialization/json_fdv2_events.hpp index 50ea455ad..fcf62af4c 100644 --- a/libs/internal/include/launchdarkly/serialization/json_fdv2_events.hpp +++ b/libs/internal/include/launchdarkly/serialization/json_fdv2_events.hpp @@ -45,6 +45,10 @@ struct PayloadTransferred { struct Goodbye { std::optional reason; + // If set, indicates an FDv1 fallback directive with this TTL in seconds. + std::optional protocol_fallback_ttl; + // If set, indicates a Retry-After equivalent in seconds. + std::optional retry_after; }; struct FDv2Error { diff --git a/libs/internal/src/serialization/json_fdv2_events.cpp b/libs/internal/src/serialization/json_fdv2_events.cpp index 63fba0d38..dc14d0205 100644 --- a/libs/internal/src/serialization/json_fdv2_events.cpp +++ b/libs/internal/src/serialization/json_fdv2_events.cpp @@ -132,6 +132,9 @@ tl::expected, JsonError> tag_invoke( Goodbye goodbye{}; PARSE_CONDITIONAL_FIELD(goodbye.reason, obj, "reason"); + PARSE_CONDITIONAL_FIELD(goodbye.protocol_fallback_ttl, obj, + "protocolFallbackTTL"); + PARSE_CONDITIONAL_FIELD(goodbye.retry_after, obj, "retryAfter"); return goodbye; } diff --git a/libs/internal/tests/fdv2_serialization_test.cpp b/libs/internal/tests/fdv2_serialization_test.cpp index 8083fa03b..fa194a103 100644 --- a/libs/internal/tests/fdv2_serialization_test.cpp +++ b/libs/internal/tests/fdv2_serialization_test.cpp @@ -363,6 +363,26 @@ TEST(GoodbyeTests, DeserializesWithoutReason) { ASSERT_FALSE(result.value()->reason); } +TEST(GoodbyeTests, DeserializesWithProtocolFallbackTtl) { + auto result = + boost::json::value_to, JsonError>>( + boost::json::parse(R"({"protocolFallbackTTL":60})")); + ASSERT_TRUE(result); + ASSERT_TRUE(result.value()); + ASSERT_TRUE(result.value()->protocol_fallback_ttl); + ASSERT_EQ(60, *result.value()->protocol_fallback_ttl); +} + +TEST(GoodbyeTests, DeserializesWithRetryAfter) { + auto result = + boost::json::value_to, JsonError>>( + boost::json::parse(R"({"retryAfter":5})")); + ASSERT_TRUE(result); + ASSERT_TRUE(result.value()); + ASSERT_TRUE(result.value()->retry_after); + ASSERT_EQ(5, *result.value()->retry_after); +} + TEST(GoodbyeTests, WrongTypeReturnsSchemaFailure) { auto result = boost::json::value_to, JsonError>>( diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv2_polling_impl.cpp b/libs/server-sdk/src/data_systems/fdv2/fdv2_polling_impl.cpp index 7d18deea5..157eddb99 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv2_polling_impl.cpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv2_polling_impl.cpp @@ -129,7 +129,12 @@ static FDv2SourceResult ParseFDv2PollEvents( FDv2SourceResult::ChangeSet{std::move(*typed)}}; } if (auto* goodbye = std::get_if(&result)) { - return FDv2SourceResult{FDv2SourceResult::Goodbye{goodbye->reason}}; + FDv2SourceResult result{FDv2SourceResult::Goodbye{goodbye->reason}}; + if (goodbye->protocol_fallback_ttl) { + result.fdv1_fallback = data_interfaces::FDv1FallbackDirective{ + std::chrono::seconds(*goodbye->protocol_fallback_ttl)}; + } + return result; } if (auto* error = std::get_if(&result)) { if (error->kind == FDv2ProtocolHandler::Error::Kind::kServerError) { @@ -228,7 +233,11 @@ data_interfaces::FDv2SourceResult HandleFDv2PollResponse( << identity << ": " << interrupted->error.Message(); } } - result.fdv1_fallback = fdv1_fallback; + // An explicit directive parsed from the response body (e.g. via a + // goodbye event) takes precedence over the HTTP response header. + if (!result.fdv1_fallback) { + result.fdv1_fallback = fdv1_fallback; + } return result; } diff --git a/libs/server-sdk/src/data_systems/fdv2/streaming_synchronizer.cpp b/libs/server-sdk/src/data_systems/fdv2/streaming_synchronizer.cpp index 868725630..5e658e319 100644 --- a/libs/server-sdk/src/data_systems/fdv2/streaming_synchronizer.cpp +++ b/libs/server-sdk/src/data_systems/fdv2/streaming_synchronizer.cpp @@ -253,7 +253,14 @@ void FDv2StreamingSynchronizer::State::OnEvent(sse::Event const& event) { << ": Goodbye was received from the LaunchDarkly " "connection with reason: '" << r.reason.value_or("") << "'."; - Notify(FDv2SourceResult{FDv2SourceResult::Goodbye{r.reason}}); + FDv2SourceResult goodbye_result{ + FDv2SourceResult::Goodbye{r.reason}}; + if (r.protocol_fallback_ttl) { + goodbye_result.fdv1_fallback = + data_interfaces::FDv1FallbackDirective{ + std::chrono::seconds(*r.protocol_fallback_ttl)}; + } + Notify(std::move(goodbye_result)); // Drop the current connection and reconnect; the protocol // handler is reset so the new connection starts in a clean // state. @@ -324,7 +331,12 @@ void FDv2StreamingSynchronizer::State::Notify(FDv2SourceResult result) { std::optional> promise; { std::lock_guard lock(mutex_); - result.fdv1_fallback = latest_fdv1_fallback_; + // An explicit directive on the result (e.g. parsed from a goodbye + // message) takes precedence over the most recent HTTP response + // header. + if (!result.fdv1_fallback) { + result.fdv1_fallback = latest_fdv1_fallback_; + } if (pending_promise_) { promise = std::move(pending_promise_); pending_promise_.reset(); From 8f19a0e5d2ba0ad40ac01528e8a06b75cf18a1cd Mon Sep 17 00:00:00 2001 From: Bee Klimt Date: Mon, 8 Jun 2026 16:27:17 -0700 Subject: [PATCH 10/17] feat: schedule FDv2 retry after FDv1 fallback TTL --- .../data_systems/fdv2/fdv2_data_system.cpp | 67 +++++++++- .../data_systems/fdv2/fdv2_data_system.hpp | 13 ++ .../src/data_systems/fdv2/source_manager.cpp | 8 ++ .../src/data_systems/fdv2/source_manager.hpp | 6 + .../tests/fdv2_data_system_test.cpp | 123 ++++++++++++++++-- libs/server-sdk/tests/source_manager_test.cpp | 41 ++++++ 6 files changed, 246 insertions(+), 12 deletions(-) diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp index 58d5b6f3b..16bc7d8a0 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp @@ -1,6 +1,7 @@ #include "fdv2_data_system.hpp" #include +#include #include @@ -59,6 +60,7 @@ FDv2DataSystem::~FDv2DataSystem() { void FDv2DataSystem::Close() { std::lock_guard lock(mutex_); closed_ = true; + fdv1_fallback_retry_cancel_.Cancel(); if (active_initializer_) { active_initializer_->Close(); } @@ -147,6 +149,7 @@ void FDv2DataSystem::OnInitializerResult( bool got_basis = false; bool got_shutdown = false; + bool disconnected = false; std::visit( overloaded{ @@ -195,16 +198,25 @@ void FDv2DataSystem::OnInitializerResult( if (source_manager_.AvailableSynchronizerCount() > 0) { LD_LOG(logger_, LogLevel::kInfo) << Identity() << ": FDv1 fallback engaged"; + got_basis = true; } else { LD_LOG(logger_, LogLevel::kWarn) << Identity() << ": FDv1 fallback directive received; no FDv1 " "fallback synchronizer configured"; + disconnected = true; } - got_basis = true; + ScheduleFDv2RetryLocked(result.fdv1_fallback->ttl); } } + if (disconnected) { + status_manager_->SetState( + DataSourceStatus::DataSourceState::kInterrupted, + DataSourceStatus::ErrorInfo::ErrorKind::kUnknown, + "FDv1 fallback directive received; no FDv1 fallback configured"); + return; + } if (got_basis) { StartSynchronizers(); } else { @@ -335,6 +347,7 @@ void FDv2DataSystem::OnSynchronizerResult( bool got_shutdown = false; bool advance = false; + bool disconnected = false; std::visit( overloaded{ @@ -378,18 +391,20 @@ void FDv2DataSystem::OnSynchronizerResult( if (result.fdv1_fallback && !source_manager_.IsCurrentSynchronizerFDv1Fallback()) { source_manager_.SwitchToFDv1Fallback(); + active_synchronizer_.reset(); + active_conditions_.reset(); if (source_manager_.AvailableSynchronizerCount() > 0) { LD_LOG(logger_, LogLevel::kInfo) << Identity() << ": FDv1 fallback engaged"; + advance = true; } else { LD_LOG(logger_, LogLevel::kWarn) << Identity() << ": FDv1 fallback directive received; no FDv1 " "fallback synchronizer configured"; + disconnected = true; } - active_synchronizer_.reset(); - active_conditions_.reset(); - advance = true; + ScheduleFDv2RetryLocked(result.fdv1_fallback->ttl); } else if (advance) { source_manager_.BlockCurrentSynchronizer(); active_synchronizer_.reset(); @@ -397,6 +412,13 @@ void FDv2DataSystem::OnSynchronizerResult( } } + if (disconnected) { + status_manager_->SetState( + DataSourceStatus::DataSourceState::kInterrupted, + DataSourceStatus::ErrorInfo::ErrorKind::kUnknown, + "FDv1 fallback directive received; no FDv1 fallback configured"); + return; + } if (advance) { StartSynchronizers(); } else { @@ -404,6 +426,43 @@ void FDv2DataSystem::OnSynchronizerResult( } } +void FDv2DataSystem::ScheduleFDv2RetryLocked(std::chrono::seconds ttl) { + if (ttl == std::chrono::seconds::zero()) { + return; + } + LD_LOG(logger_, LogLevel::kInfo) + << Identity() << ": FDv2 retry scheduled in " << ttl.count() << "s"; + async::Delay(ioc_, ttl, fdv1_fallback_retry_cancel_.GetToken()) + .Then( + [this](bool fired) -> std::monostate { + if (fired) { + OnFDv1RetryTimer(); + } + return {}; + }, + [ioc = ioc_](async::Continuation work) { + boost::asio::post(ioc, std::move(work)); + }); +} + +void FDv2DataSystem::OnFDv1RetryTimer() { + { + std::lock_guard lock(mutex_); + if (closed_) { + return; + } + LD_LOG(logger_, LogLevel::kInfo) + << Identity() << ": FDv2 retry timer fired; re-engaging FDv2"; + source_manager_.SwitchBackToFDv2(); + if (active_synchronizer_) { + active_synchronizer_->Close(); + active_synchronizer_.reset(); + } + active_conditions_.reset(); + } + StartSynchronizers(); +} + void FDv2DataSystem::ApplyChangeSet( data_model::ChangeSet change_set) { if (change_set.selector.value.has_value()) { diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.hpp b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.hpp index 2eb243140..3c7147ec1 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.hpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.hpp @@ -10,12 +10,14 @@ #include "conditions.hpp" #include "source_manager.hpp" +#include #include #include #include #include +#include #include #include #include @@ -247,6 +249,14 @@ class FDv2DataSystem final : public data_interfaces::IDataSystem { void OnSynchronizerResult(data_interfaces::FDv2SourceResult result); void OnConditionFired(data_interfaces::IFDv2Condition::Type type); + // Schedules an FDv2 recovery attempt after the given TTL. Called with + // mutex_ held. TTL of 0 disables the recovery and is a no-op. + void ScheduleFDv2RetryLocked(std::chrono::seconds ttl); + + // Invoked when the FDv1 fallback TTL expires. Switches the source list + // back to FDv2 and restarts the synchronizer phase. + void OnFDv1RetryTimer(); + // Builds the conditions to apply to the currently active synchronizer. // Must be called with mutex_ held; reads source_manager_ state. std::unique_ptr BuildActiveConditions() const; @@ -291,6 +301,9 @@ class FDv2DataSystem final : public data_interfaces::IDataSystem { std::unique_ptr active_initializer_; std::unique_ptr active_synchronizer_; std::unique_ptr active_conditions_; + + // Cancelled in Close() to abort any pending FDv1 fallback retry delay. + async::CancellationSource fdv1_fallback_retry_cancel_; }; } // namespace launchdarkly::server_side::data_systems diff --git a/libs/server-sdk/src/data_systems/fdv2/source_manager.cpp b/libs/server-sdk/src/data_systems/fdv2/source_manager.cpp index 4af2405a6..3f020e404 100644 --- a/libs/server-sdk/src/data_systems/fdv2/source_manager.cpp +++ b/libs/server-sdk/src/data_systems/fdv2/source_manager.cpp @@ -54,6 +54,14 @@ void SourceManager::SwitchToFDv1Fallback() { synchronizer_index_ = -1; } +void SourceManager::SwitchBackToFDv2() { + for (auto& entry : synchronizers_) { + entry.state = + entry.is_fdv1_fallback ? State::kBlocked : State::kAvailable; + } + synchronizer_index_ = -1; +} + bool SourceManager::IsPrimeSynchronizer() const { for (std::size_t i = 0; i < synchronizers_.size(); ++i) { if (synchronizers_[i].state == State::kAvailable) { diff --git a/libs/server-sdk/src/data_systems/fdv2/source_manager.hpp b/libs/server-sdk/src/data_systems/fdv2/source_manager.hpp index bd2347ccf..264dfd494 100644 --- a/libs/server-sdk/src/data_systems/fdv2/source_manager.hpp +++ b/libs/server-sdk/src/data_systems/fdv2/source_manager.hpp @@ -61,6 +61,12 @@ class SourceManager { */ void SwitchToFDv1Fallback(); + /** + * Returns synchronizer state to the initial configuration, including + * unblocking factories previously blocked by terminal errors. + */ + void SwitchBackToFDv2(); + /** * Returns true if the currently tracked factory is the first Available * factory in the list. Returns false if no factory is currently tracked. diff --git a/libs/server-sdk/tests/fdv2_data_system_test.cpp b/libs/server-sdk/tests/fdv2_data_system_test.cpp index 96e2fc33d..e7d170ccd 100644 --- a/libs/server-sdk/tests/fdv2_data_system_test.cpp +++ b/libs/server-sdk/tests/fdv2_data_system_test.cpp @@ -1097,7 +1097,8 @@ TEST(FDv2DataSystemTest, SynchronizerFdv1FlagSwitchesToFdv1Adapter) { data_model::ChangeSetType::kNone, {}, data_model::Selector{}}}}; - r.fdv1_fallback = data_interfaces::FDv1FallbackDirective{}; + r.fdv1_fallback = + data_interfaces::FDv1FallbackDirective{std::chrono::seconds{0}}; return r; }()}); auto fdv2_factory = @@ -1124,11 +1125,13 @@ TEST(FDv2DataSystemTest, SynchronizerFdv1FlagSwitchesToFdv1Adapter) { EXPECT_EQ(1, fdv1_factory_ptr->build_count_); } -TEST(FDv2DataSystemTest, SynchronizerFdv1FlagWithoutAdapterTransitionsOff) { +TEST(FDv2DataSystemTest, + SynchronizerFdv1FlagWithoutAdapterDoesNotTransitionToOff) { auto logger = MakeNullLogger(); boost::asio::io_context ioc; data_components::DataSourceStatusManager status_manager; + // Directive with TTL=0: indefinite, no automatic FDv2 retry. auto fdv2_sync = std::make_unique(std::vector{[]() { FDv2SourceResult r{ @@ -1136,7 +1139,8 @@ TEST(FDv2DataSystemTest, SynchronizerFdv1FlagWithoutAdapterTransitionsOff) { FDv2SourceResult::ErrorInfo::ErrorKind::kErrorResponse, /*status_code=*/418, "directive", std::chrono::system_clock::now()}}}; - r.fdv1_fallback = data_interfaces::FDv1FallbackDirective{}; + r.fdv1_fallback = + data_interfaces::FDv1FallbackDirective{std::chrono::seconds{0}}; return r; }()}); auto fdv2_factory = @@ -1152,7 +1156,7 @@ TEST(FDv2DataSystemTest, SynchronizerFdv1FlagWithoutAdapterTransitionsOff) { ds.Initialize(); ioc.run(); - EXPECT_EQ(DataSourceStatus::DataSourceState::kOff, + EXPECT_NE(DataSourceStatus::DataSourceState::kOff, status_manager.Status().State()); } @@ -1167,7 +1171,8 @@ TEST(FDv2DataSystemTest, InitializerFdv1FlagSwitchesToFdv1Adapter) { FDv2SourceResult::ErrorInfo::ErrorKind::kErrorResponse, /*status_code=*/418, "directive", std::chrono::system_clock::now()}}}; - init_result.fdv1_fallback = data_interfaces::FDv1FallbackDirective{}; + init_result.fdv1_fallback = + data_interfaces::FDv1FallbackDirective{std::chrono::seconds{0}}; auto initializer = std::make_unique(std::move(init_result)); @@ -1221,7 +1226,8 @@ TEST(FDv2DataSystemTest, ItemChange{"flagA", data_model::FlagDescriptor(flag_a)}, }, MakeSelector(1, "state-1")); - init_result.fdv1_fallback = data_interfaces::FDv1FallbackDirective{}; + init_result.fdv1_fallback = + data_interfaces::FDv1FallbackDirective{std::chrono::seconds{0}}; auto initializer = std::make_unique(std::move(init_result)); @@ -1264,6 +1270,105 @@ TEST(FDv2DataSystemTest, EXPECT_EQ(1, fdv1_factory_ptr->build_count_); } +TEST(FDv2DataSystemTest, DirectiveTtlElapseRebuildsFDv2) { + auto logger = MakeNullLogger(); + boost::asio::io_context ioc; + data_components::DataSourceStatusManager status_manager; + + // First build: source emits the directive with a 1s TTL. Second build + // (after the TTL elapses): source returns no results, so MockSynchronizer + // emits Shutdown and orchestration ends. + auto first_sync = + std::make_unique(std::vector{[]() { + FDv2SourceResult r{ + FDv2SourceResult::Interrupted{FDv2SourceResult::ErrorInfo{ + FDv2SourceResult::ErrorInfo::ErrorKind::kErrorResponse, + /*status_code=*/418, "directive", + std::chrono::system_clock::now()}}}; + r.fdv1_fallback = + data_interfaces::FDv1FallbackDirective{std::chrono::seconds{1}}; + return r; + }()}); + auto second_sync = + std::make_unique(std::vector{}); + + std::vector> sources; + sources.push_back(std::move(first_sync)); + sources.push_back(std::move(second_sync)); + auto factory = + std::make_unique(std::move(sources)); + auto* factory_ptr = factory.get(); + + std::vector> synchronizers; + synchronizers.push_back(std::move(factory)); + + FDv2DataSystem ds({}, std::move(synchronizers), + /*fallback_condition_factory=*/nullptr, + /*recovery_condition_factory=*/nullptr, + ioc.get_executor(), &status_manager, logger); + ds.Initialize(); + ioc.run(); + + EXPECT_EQ(2, factory_ptr->build_count_); +} + +TEST(FDv2DataSystemTest, FDv2RecoveryAfterTtlAcceptsValidData) { + auto logger = MakeNullLogger(); + boost::asio::io_context ioc; + data_components::DataSourceStatusManager status_manager; + + // First build: emits directive with 1s TTL. Second build (recovery): + // emits a valid ChangeSet without the directive. + auto first_sync = + std::make_unique(std::vector{[]() { + FDv2SourceResult r{ + FDv2SourceResult::Interrupted{FDv2SourceResult::ErrorInfo{ + FDv2SourceResult::ErrorInfo::ErrorKind::kErrorResponse, + /*status_code=*/418, "directive", + std::chrono::system_clock::now()}}}; + r.fdv1_fallback = + data_interfaces::FDv1FallbackDirective{std::chrono::seconds{1}}; + return r; + }()}); + + data_model::Flag flag_a; + flag_a.key = "flagA"; + flag_a.version = 1; + + auto second_sync = std::make_unique( + std::vector{MakeFullChangeSetResult( + ChangeSetData{ + ItemChange{"flagA", data_model::FlagDescriptor(flag_a)}, + }, + MakeSelector(1, "state-1"))}); + + std::vector> sources; + sources.push_back(std::move(first_sync)); + sources.push_back(std::move(second_sync)); + auto factory = + std::make_unique(std::move(sources)); + auto* factory_ptr = factory.get(); + + std::vector> synchronizers; + synchronizers.push_back(std::move(factory)); + + FDv2DataSystem ds({}, std::move(synchronizers), + /*fallback_condition_factory=*/nullptr, + /*recovery_condition_factory=*/nullptr, + ioc.get_executor(), &status_manager, logger); + ds.Initialize(); + ioc.run(); + + // FDv2 was rebuilt after the TTL elapsed, the new ChangeSet was applied, + // and the data system is in the valid state. + EXPECT_EQ(2, factory_ptr->build_count_); + EXPECT_TRUE(ds.Initialized()); + EXPECT_EQ(DataSourceStatus::DataSourceState::kValid, + status_manager.Status().State()); + auto fetched = ds.GetFlag("flagA"); + ASSERT_TRUE(fetched); +} + TEST(FDv2DataSystemTest, FDv1SourceSelfDirectiveDoesNotRebuildFDv1) { auto logger = MakeNullLogger(); boost::asio::io_context ioc; @@ -1278,7 +1383,8 @@ TEST(FDv2DataSystemTest, FDv1SourceSelfDirectiveDoesNotRebuildFDv1) { data_model::ChangeSetType::kNone, {}, data_model::Selector{}}}}; - r.fdv1_fallback = data_interfaces::FDv1FallbackDirective{}; + r.fdv1_fallback = + data_interfaces::FDv1FallbackDirective{std::chrono::seconds{0}}; return r; }()}); auto fdv2_factory = @@ -1294,7 +1400,8 @@ TEST(FDv2DataSystemTest, FDv1SourceSelfDirectiveDoesNotRebuildFDv1) { FDv2SourceResult::ErrorInfo::ErrorKind::kErrorResponse, /*status_code=*/418, "self-trigger", std::chrono::system_clock::now()}}}; - r.fdv1_fallback = data_interfaces::FDv1FallbackDirective{}; + r.fdv1_fallback = + data_interfaces::FDv1FallbackDirective{std::chrono::seconds{0}}; return r; }()}); auto fdv1_factory = diff --git a/libs/server-sdk/tests/source_manager_test.cpp b/libs/server-sdk/tests/source_manager_test.cpp index 77b207b46..68bfd5cc2 100644 --- a/libs/server-sdk/tests/source_manager_test.cpp +++ b/libs/server-sdk/tests/source_manager_test.cpp @@ -255,3 +255,44 @@ TEST(SourceManagerTest, SwitchToFDv1FallbackUnblocksPreviouslyBlockedFDv2) { EXPECT_EQ(1, fdv1_ptr->build_count); EXPECT_TRUE(mgr.IsCurrentSynchronizerFDv1Fallback()); } + +TEST(SourceManagerTest, SwitchBackToFDv2UnblocksFDv2AndBlocksFDv1) { + auto fdv2 = std::make_unique(); + auto* fdv2_ptr = fdv2.get(); + auto fdv1 = std::make_unique(); + std::vector> factories; + factories.push_back(std::move(fdv2)); + factories.push_back(std::move(fdv1)); + SourceManager mgr(std::move(factories)); + + // Switch to FDv1 first, then back to FDv2. + mgr.SwitchToFDv1Fallback(); + mgr.SwitchBackToFDv2(); + + EXPECT_EQ(1u, mgr.AvailableSynchronizerCount()); + auto sync = mgr.NextSynchronizer(); + ASSERT_NE(sync, nullptr); + EXPECT_EQ(1, fdv2_ptr->build_count); + EXPECT_FALSE(mgr.IsCurrentSynchronizerFDv1Fallback()); +} + +TEST(SourceManagerTest, SwitchBackToFDv2UnblocksTerminallyFailedFDv2Factory) { + auto fdv2 = std::make_unique(); + auto* fdv2_ptr = fdv2.get(); + std::vector> factories; + factories.push_back(std::move(fdv2)); + SourceManager mgr(std::move(factories)); + + // Simulate a terminal error blocking the FDv2 factory. + mgr.NextSynchronizer(); + mgr.BlockCurrentSynchronizer(); + EXPECT_EQ(0u, mgr.AvailableSynchronizerCount()); + + mgr.SwitchBackToFDv2(); + + // Previously-blocked FDv2 factory is now available again. + EXPECT_EQ(1u, mgr.AvailableSynchronizerCount()); + auto sync = mgr.NextSynchronizer(); + ASSERT_NE(sync, nullptr); + EXPECT_EQ(2, fdv2_ptr->build_count); +} From 303b3a87041107936d05cead2035b4ee3ea5fff4 Mon Sep 17 00:00:00 2001 From: Bee Klimt Date: Mon, 8 Jun 2026 17:07:28 -0700 Subject: [PATCH 11/17] chore: remove unused retry_after field from goodbye --- .../launchdarkly/serialization/json_fdv2_events.hpp | 2 -- libs/internal/src/serialization/json_fdv2_events.cpp | 1 - libs/internal/tests/fdv2_serialization_test.cpp | 10 ---------- 3 files changed, 13 deletions(-) diff --git a/libs/internal/include/launchdarkly/serialization/json_fdv2_events.hpp b/libs/internal/include/launchdarkly/serialization/json_fdv2_events.hpp index fcf62af4c..3088b859c 100644 --- a/libs/internal/include/launchdarkly/serialization/json_fdv2_events.hpp +++ b/libs/internal/include/launchdarkly/serialization/json_fdv2_events.hpp @@ -47,8 +47,6 @@ struct Goodbye { std::optional reason; // If set, indicates an FDv1 fallback directive with this TTL in seconds. std::optional protocol_fallback_ttl; - // If set, indicates a Retry-After equivalent in seconds. - std::optional retry_after; }; struct FDv2Error { diff --git a/libs/internal/src/serialization/json_fdv2_events.cpp b/libs/internal/src/serialization/json_fdv2_events.cpp index dc14d0205..34dfa99cf 100644 --- a/libs/internal/src/serialization/json_fdv2_events.cpp +++ b/libs/internal/src/serialization/json_fdv2_events.cpp @@ -134,7 +134,6 @@ tl::expected, JsonError> tag_invoke( PARSE_CONDITIONAL_FIELD(goodbye.reason, obj, "reason"); PARSE_CONDITIONAL_FIELD(goodbye.protocol_fallback_ttl, obj, "protocolFallbackTTL"); - PARSE_CONDITIONAL_FIELD(goodbye.retry_after, obj, "retryAfter"); return goodbye; } diff --git a/libs/internal/tests/fdv2_serialization_test.cpp b/libs/internal/tests/fdv2_serialization_test.cpp index fa194a103..1df425bc0 100644 --- a/libs/internal/tests/fdv2_serialization_test.cpp +++ b/libs/internal/tests/fdv2_serialization_test.cpp @@ -373,16 +373,6 @@ TEST(GoodbyeTests, DeserializesWithProtocolFallbackTtl) { ASSERT_EQ(60, *result.value()->protocol_fallback_ttl); } -TEST(GoodbyeTests, DeserializesWithRetryAfter) { - auto result = - boost::json::value_to, JsonError>>( - boost::json::parse(R"({"retryAfter":5})")); - ASSERT_TRUE(result); - ASSERT_TRUE(result.value()); - ASSERT_TRUE(result.value()->retry_after); - ASSERT_EQ(5, *result.value()->retry_after); -} - TEST(GoodbyeTests, WrongTypeReturnsSchemaFailure) { auto result = boost::json::value_to, JsonError>>( From b1157e18f6bb0388a32c50379a1fac5528242db6 Mon Sep 17 00:00:00 2001 From: Bee Klimt Date: Tue, 9 Jun 2026 10:07:36 -0700 Subject: [PATCH 12/17] feat: translate FDv1 status changes to FDv2 results in FDv1AdapterSynchronizer --- .../fdv2/fdv1_adapter_synchronizer.cpp | 26 +++- .../fdv2/fdv1_adapter_synchronizer.hpp | 33 ++++- .../tests/fdv1_adapter_synchronizer_test.cpp | 119 +++++++++++++++--- 3 files changed, 155 insertions(+), 23 deletions(-) diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.cpp b/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.cpp index 2dfd953cb..0fd6094d3 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.cpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.cpp @@ -5,6 +5,7 @@ namespace launchdarkly::server_side::data_systems { using data_interfaces::FDv2SourceResult; +using DataSourceState = DataSourceStatus::DataSourceState; // ----- State ----- @@ -132,9 +133,32 @@ std::string const& FDv1AdapterSynchronizer::ConvertingDestination::Identity() // ----- FDv1AdapterSynchronizer ----- FDv1AdapterSynchronizer::FDv1AdapterSynchronizer( - std::unique_ptr fdv1_source) + std::unique_ptr fdv1_source, + data_components::DataSourceStatusManager* status_manager) : state_(std::make_shared()), destination_(std::make_unique(state_)), + status_manager_(status_manager), + status_subscription_(status_manager_->OnDataSourceStatusChange( + [state = state_](DataSourceStatus status) { + auto error = status.LastError(); + if (!error) { + return; + } + switch (status.State()) { + case DataSourceState::kInterrupted: + state->Notify(FDv2SourceResult{ + FDv2SourceResult::Interrupted{*error}}); + break; + case DataSourceState::kOff: + state->Notify(FDv2SourceResult{ + FDv2SourceResult::TerminalError{*error}}); + break; + case DataSourceState::kInitializing: + case DataSourceState::kValid: + // No FDv2 result for these states. + break; + } + })), fdv1_source_(std::move(fdv1_source)) {} FDv1AdapterSynchronizer::~FDv1AdapterSynchronizer() { diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.hpp b/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.hpp index 7d2d10a3e..e52b1b321 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.hpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.hpp @@ -1,10 +1,12 @@ #pragma once +#include "../../data_components/status_notifications/data_source_status_manager.hpp" #include "../../data_interfaces/destination/idestination.hpp" #include "../../data_interfaces/source/idata_synchronizer.hpp" #include "../../data_interfaces/source/ifdv2_synchronizer.hpp" #include +#include #include #include @@ -23,15 +25,26 @@ namespace launchdarkly::server_side::data_systems { * and fdv1_fallback = false (the directive does not re-fire from FDv1 data). * * Threading: Next() and Close() may be called from any thread; only one - * Next() may be outstanding at a time. The adapter blocks in its destructor - * waiting for the FDv1 source's ShutdownAsync completion, so no callbacks - * are in flight when the wrapped source is destroyed. + * Next() may be outstanding at a time. Member declaration order ensures + * the wrapped FDv1 source destructs before destination_ and state_, so any + * in-flight FDv1 callbacks land on live objects during teardown. This + * relies on the wrapped IDataSynchronizer blocking on its in-flight work + * in its destructor. */ class FDv1AdapterSynchronizer final : public data_interfaces::IFDv2Synchronizer { public: - explicit FDv1AdapterSynchronizer( - std::unique_ptr fdv1_source); + /** + * @param fdv1_source The wrapped source. Must have been constructed + * with status_manager as its status sink so that + * state changes flow back into this adapter. + * @param status_manager Non-owning. The caller retains ownership and + * must keep it alive for the lifetime of the + * wrapped source and this adapter. + */ + FDv1AdapterSynchronizer( + std::unique_ptr fdv1_source, + data_components::DataSourceStatusManager* status_manager); ~FDv1AdapterSynchronizer() override; @@ -95,9 +108,17 @@ class FDv1AdapterSynchronizer final std::weak_ptr state_; }; - // const after construction. + // shared_ptr so async callbacks that may fire after this is destroyed + // can hold their own reference. std::shared_ptr const state_; std::unique_ptr const destination_; + + // Non-owning. The caller must keep this alive for the lifetime of + // the wrapped source, which holds a reference to it for status + // reporting. + data_components::DataSourceStatusManager* const status_manager_; + std::unique_ptr const status_subscription_; + std::unique_ptr const fdv1_source_; // Thread-safe primitive. diff --git a/libs/server-sdk/tests/fdv1_adapter_synchronizer_test.cpp b/libs/server-sdk/tests/fdv1_adapter_synchronizer_test.cpp index 77058f6bc..da1408b94 100644 --- a/libs/server-sdk/tests/fdv1_adapter_synchronizer_test.cpp +++ b/libs/server-sdk/tests/fdv1_adapter_synchronizer_test.cpp @@ -8,6 +8,8 @@ #include using namespace launchdarkly; +using namespace launchdarkly::server_side; +using namespace launchdarkly::server_side::data_components; using namespace launchdarkly::server_side::data_interfaces; using namespace launchdarkly::server_side::data_systems; using namespace std::chrono_literals; @@ -18,6 +20,8 @@ namespace { // the IDestination it was given so the test can drive Init/Upsert. class MockFDv1Source final : public IDataSynchronizer { public: + explicit MockFDv1Source(DataSourceStatusManager& /*status_manager*/) {} + void StartAsync(IDestination* destination, data_model::SDKDataSet const* bootstrap) override { ++start_count; @@ -46,9 +50,10 @@ class MockFDv1Source final : public IDataSynchronizer { } // namespace TEST(FDv1AdapterSynchronizerTest, FirstNextStartsFDv1Source) { - auto source = std::make_unique(); + DataSourceStatusManager status_manager; + auto source = std::make_unique(status_manager); auto* source_ptr = source.get(); - FDv1AdapterSynchronizer adapter(std::move(source)); + FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); auto future = adapter.Next(data_model::Selector{}); @@ -58,9 +63,10 @@ TEST(FDv1AdapterSynchronizerTest, FirstNextStartsFDv1Source) { } TEST(FDv1AdapterSynchronizerTest, SecondNextDoesNotRestartSource) { - auto source = std::make_unique(); + DataSourceStatusManager status_manager; + auto source = std::make_unique(status_manager); auto* source_ptr = source.get(); - FDv1AdapterSynchronizer adapter(std::move(source)); + FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); auto first = adapter.Next(data_model::Selector{}); source_ptr->destination_->Init(data_model::SDKDataSet{}); @@ -72,9 +78,10 @@ TEST(FDv1AdapterSynchronizerTest, SecondNextDoesNotRestartSource) { } TEST(FDv1AdapterSynchronizerTest, FDv1InitProducesFullChangeSet) { - auto source = std::make_unique(); + DataSourceStatusManager status_manager; + auto source = std::make_unique(status_manager); auto* source_ptr = source.get(); - FDv1AdapterSynchronizer adapter(std::move(source)); + FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); auto future = adapter.Next(data_model::Selector{}); @@ -97,9 +104,10 @@ TEST(FDv1AdapterSynchronizerTest, FDv1InitProducesFullChangeSet) { } TEST(FDv1AdapterSynchronizerTest, FDv1UpsertProducesPartialChangeSet) { - auto source = std::make_unique(); + DataSourceStatusManager status_manager; + auto source = std::make_unique(status_manager); auto* source_ptr = source.get(); - FDv1AdapterSynchronizer adapter(std::move(source)); + FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); // Flag upsert. auto flag_future = adapter.Next(data_model::Selector{}); @@ -138,8 +146,9 @@ TEST(FDv1AdapterSynchronizerTest, FDv1UpsertProducesPartialChangeSet) { } TEST(FDv1AdapterSynchronizerTest, ClosePendingNextReturnsShutdown) { - auto source = std::make_unique(); - FDv1AdapterSynchronizer adapter(std::move(source)); + DataSourceStatusManager status_manager; + auto source = std::make_unique(status_manager); + FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); auto future = adapter.Next(data_model::Selector{}); EXPECT_FALSE(future.IsFinished()); @@ -153,9 +162,10 @@ TEST(FDv1AdapterSynchronizerTest, ClosePendingNextReturnsShutdown) { } TEST(FDv1AdapterSynchronizerTest, CloseShutsDownStartedFDv1Source) { - auto source = std::make_unique(); + DataSourceStatusManager status_manager; + auto source = std::make_unique(status_manager); auto* source_ptr = source.get(); - FDv1AdapterSynchronizer adapter(std::move(source)); + FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); adapter.Next(data_model::Selector{}); adapter.Close(); @@ -164,9 +174,10 @@ TEST(FDv1AdapterSynchronizerTest, CloseShutsDownStartedFDv1Source) { } TEST(FDv1AdapterSynchronizerTest, CloseWithoutStartDoesNotShutDownFDv1Source) { - auto source = std::make_unique(); + DataSourceStatusManager status_manager; + auto source = std::make_unique(status_manager); auto* source_ptr = source.get(); - FDv1AdapterSynchronizer adapter(std::move(source)); + FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); // No Next() call — FDv1 source was never started. adapter.Close(); @@ -175,9 +186,85 @@ TEST(FDv1AdapterSynchronizerTest, CloseWithoutStartDoesNotShutDownFDv1Source) { EXPECT_EQ(0, source_ptr->shutdown_count); } +TEST(FDv1AdapterSynchronizerTest, QueuedResultsDrainInFifoOrder) { + DataSourceStatusManager status_manager; + auto source = std::make_unique(status_manager); + auto* source_ptr = source.get(); + FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); + + // Start the source by satisfying one Next() with an Init. + auto first = adapter.Next(data_model::Selector{}); + source_ptr->destination_->Init(data_model::SDKDataSet{}); + first.WaitForResult(1s); + + // Two upserts queue with no Next() in flight. + data_model::Flag flag_a; + flag_a.key = "a"; + data_model::Flag flag_b; + flag_b.key = "b"; + source_ptr->destination_->Upsert("a", data_model::FlagDescriptor(flag_a)); + source_ptr->destination_->Upsert("b", data_model::FlagDescriptor(flag_b)); + + // Drain in FIFO order. + auto r1 = adapter.Next(data_model::Selector{}).WaitForResult(1s); + auto r2 = adapter.Next(data_model::Selector{}).WaitForResult(1s); + ASSERT_TRUE(r1.has_value()); + ASSERT_TRUE(r2.has_value()); + auto* cs1 = std::get_if(&r1->value); + auto* cs2 = std::get_if(&r2->value); + ASSERT_NE(cs1, nullptr); + ASSERT_NE(cs2, nullptr); + ASSERT_EQ(1u, cs1->change_set.data.size()); + ASSERT_EQ(1u, cs2->change_set.data.size()); + EXPECT_EQ("a", cs1->change_set.data[0].key); + EXPECT_EQ("b", cs2->change_set.data[0].key); +} + +TEST(FDv1AdapterSynchronizerTest, InterruptedStatusProducesInterruptedResult) { + DataSourceStatusManager status_manager; + auto source = std::make_unique(status_manager); + FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); + + // kInterrupted from kInitializing stays kInitializing; drive past first. + status_manager.SetState(DataSourceStatus::DataSourceState::kValid); + + auto future = adapter.Next(data_model::Selector{}); + status_manager.SetState( + DataSourceStatus::DataSourceState::kInterrupted, + DataSourceStatus::ErrorInfo::ErrorKind::kNetworkError, "boom"); + + auto result = future.WaitForResult(1s); + ASSERT_TRUE(result.has_value()); + auto* interrupted = + std::get_if(&result->value); + ASSERT_NE(interrupted, nullptr); + EXPECT_EQ(DataSourceStatus::ErrorInfo::ErrorKind::kNetworkError, + interrupted->error.Kind()); +} + +TEST(FDv1AdapterSynchronizerTest, OffStatusProducesTerminalErrorResult) { + DataSourceStatusManager status_manager; + auto source = std::make_unique(status_manager); + FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); + + auto future = adapter.Next(data_model::Selector{}); + status_manager.SetState( + DataSourceStatus::DataSourceState::kOff, + DataSourceStatus::ErrorInfo::ErrorKind::kErrorResponse, "401"); + + auto result = future.WaitForResult(1s); + ASSERT_TRUE(result.has_value()); + auto* terminal = + std::get_if(&result->value); + ASSERT_NE(terminal, nullptr); + EXPECT_EQ(DataSourceStatus::ErrorInfo::ErrorKind::kErrorResponse, + terminal->error.Kind()); +} + TEST(FDv1AdapterSynchronizerTest, NextAfterCloseReturnsShutdown) { - auto source = std::make_unique(); - FDv1AdapterSynchronizer adapter(std::move(source)); + DataSourceStatusManager status_manager; + auto source = std::make_unique(status_manager); + FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); adapter.Close(); auto future = adapter.Next(data_model::Selector{}); From 9a93aabfe8bb1035c2a1edc3a08b9034cbdf57fc Mon Sep 17 00:00:00 2001 From: Bee Klimt Date: Thu, 11 Jun 2026 09:41:07 -0700 Subject: [PATCH 13/17] docs: explain got_basis reuse in FDv1 fallback branch --- libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp | 3 +++ 1 file changed, 3 insertions(+) diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp index 16bc7d8a0..222c0d147 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp @@ -198,6 +198,9 @@ void FDv2DataSystem::OnInitializerResult( if (source_manager_.AvailableSynchronizerCount() > 0) { LD_LOG(logger_, LogLevel::kInfo) << Identity() << ": FDv1 fallback engaged"; + // No basis yet; reuse the flag to fall through to + // StartSynchronizers so the FDv1 fallback synchronizer can + // produce it. got_basis = true; } else { LD_LOG(logger_, LogLevel::kWarn) From 67126a99a9e8e4747d3062afd4fc8c61f7e471af Mon Sep 17 00:00:00 2001 From: Bee Klimt Date: Thu, 11 Jun 2026 10:06:40 -0700 Subject: [PATCH 14/17] fix: reset FDv1 fallback retry source between schedules --- libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp index 222c0d147..fcb980c3c 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv2_data_system.cpp @@ -433,6 +433,11 @@ void FDv2DataSystem::ScheduleFDv2RetryLocked(std::chrono::seconds ttl) { if (ttl == std::chrono::seconds::zero()) { return; } + // Cancel any in-flight retry and start fresh; CancellationSource is + // one-shot, so reusing the same source for successive schedules would + // leak prior timers. + fdv1_fallback_retry_cancel_.Cancel(); + fdv1_fallback_retry_cancel_ = async::CancellationSource{}; LD_LOG(logger_, LogLevel::kInfo) << Identity() << ": FDv2 retry scheduled in " << ttl.count() << "s"; async::Delay(ioc_, ttl, fdv1_fallback_retry_cancel_.GetToken()) From 27f5c1ed9b95d531989b79d6bd3b2ac555bd1b92 Mon Sep 17 00:00:00 2001 From: Bee Klimt Date: Thu, 11 Jun 2026 13:15:32 -0700 Subject: [PATCH 15/17] fix: serialize StartAsync/ShutdownAsync on wrapped FDv1 source --- .../fdv2/fdv1_adapter_synchronizer.cpp | 36 +++++++++---------- .../fdv2/fdv1_adapter_synchronizer.hpp | 35 +++++++++--------- 2 files changed, 35 insertions(+), 36 deletions(-) diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.cpp b/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.cpp index 0fd6094d3..58d0362c4 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.cpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.cpp @@ -9,20 +9,9 @@ using DataSourceState = DataSourceStatus::DataSourceState; // ----- State ----- -bool FDv1AdapterSynchronizer::State::TryStart() { - std::lock_guard lock(mutex_); - if (started_ || closed_) { - return false; - } - started_ = true; - return true; -} - -bool FDv1AdapterSynchronizer::State::MarkClosed() { - std::lock_guard lock(mutex_); - closed_ = true; - return started_; -} +FDv1AdapterSynchronizer::State::State( + async::Future closed_future) + : closed_future_(std::move(closed_future)) {} async::Future FDv1AdapterSynchronizer::State::GetNext() { std::lock_guard lock(mutex_); @@ -52,7 +41,7 @@ void FDv1AdapterSynchronizer::State::Notify(FDv2SourceResult result) { std::optional> promise; { std::lock_guard lock(mutex_); - if (closed_) { + if (closed_future_.IsFinished()) { return; } if (pending_promise_) { @@ -135,7 +124,7 @@ std::string const& FDv1AdapterSynchronizer::ConvertingDestination::Identity() FDv1AdapterSynchronizer::FDv1AdapterSynchronizer( std::unique_ptr fdv1_source, data_components::DataSourceStatusManager* status_manager) - : state_(std::make_shared()), + : state_(std::make_shared(close_promise_.GetFuture())), destination_(std::make_unique(state_)), status_manager_(status_manager), status_subscription_(status_manager_->OnDataSourceStatusChange( @@ -172,9 +161,13 @@ async::Future FDv1AdapterSynchronizer::Next( return async::MakeFuture( FDv2SourceResult{FDv2SourceResult::Shutdown{}}); } - if (state_->TryStart()) { - fdv1_source_->StartAsync(destination_.get(), - /*bootstrap_data=*/nullptr); + { + std::lock_guard lock(lifecycle_mutex_); + if (!started_) { + started_ = true; + fdv1_source_->StartAsync(destination_.get(), + /*bootstrap_data=*/nullptr); + } } auto result_future = state_->GetNext(); if (result_future.IsFinished()) { @@ -198,7 +191,10 @@ void FDv1AdapterSynchronizer::Close() { if (!close_promise_.Resolve(std::monostate{})) { return; } - if (state_->MarkClosed()) { + std::lock_guard lock(lifecycle_mutex_); + bool const was_started = started_; + started_ = true; + if (was_started) { fdv1_source_->ShutdownAsync([] {}); } } diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.hpp b/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.hpp index e52b1b321..8c0085cdf 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.hpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.hpp @@ -55,21 +55,13 @@ class FDv1AdapterSynchronizer final private: /** - * Holds the lifecycle, result queue, and pending Next() promise; shared - * with the FDv1 source's IDestination via the inner ConvertingDestination. + * Holds the result queue and pending Next() promise; shared with the + * FDv1 source's IDestination via the inner ConvertingDestination. * All methods are thread-safe. */ class State { public: - // Returns true if this call transitioned Initial → Started; false if - // already started or already closed. Used to gate the one-time - // StartAsync call on the wrapped FDv1 source. - bool TryStart(); - - // Marks the state closed and returns whether the source was started - // before the transition (so the caller knows whether ShutdownAsync - // needs to be called). - bool MarkClosed(); + explicit State(async::Future closed_future); async::Future GetNext(); @@ -81,10 +73,12 @@ class FDv1AdapterSynchronizer final void Notify(data_interfaces::FDv2SourceResult result); private: - // Protected by mutex_. + // Finished once the owning FDv1AdapterSynchronizer's close_promise_ + // is resolved. Read in Notify to drop late results. + async::Future const closed_future_; + mutable std::mutex mutex_; - bool started_ = false; - bool closed_ = false; + // Protected by mutex_. std::optional> pending_promise_; std::deque result_queue_; @@ -108,6 +102,10 @@ class FDv1AdapterSynchronizer final std::weak_ptr state_; }; + // Thread-safe primitive. Declared before state_ so state_'s constructor + // can take a future from it. + async::Promise close_promise_; + // shared_ptr so async callbacks that may fire after this is destroyed // can hold their own reference. std::shared_ptr const state_; @@ -121,8 +119,13 @@ class FDv1AdapterSynchronizer final std::unique_ptr const fdv1_source_; - // Thread-safe primitive. - async::Promise close_promise_; + // Serializes StartAsync and ShutdownAsync on fdv1_source_ across + // concurrent Next() and Close() calls. + std::mutex lifecycle_mutex_; + // Protected by lifecycle_mutex_. Set when Next() calls StartAsync, or + // when Close() runs without a prior start (to gate any later Next() + // from calling StartAsync after Close). + bool started_ = false; }; } // namespace launchdarkly::server_side::data_systems From 6c428c526c7c473ac4e8fa50c9706bfaa64a1fd9 Mon Sep 17 00:00:00 2001 From: Bee Klimt Date: Thu, 11 Jun 2026 15:06:18 -0700 Subject: [PATCH 16/17] fix: give FDv1 adapter a private status manager --- .../fdv2/fdv1_adapter_synchronizer.cpp | 9 +- .../fdv2/fdv1_adapter_synchronizer.hpp | 25 ++-- .../tests/fdv1_adapter_synchronizer_test.cpp | 111 +++++++++--------- 3 files changed, 70 insertions(+), 75 deletions(-) diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.cpp b/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.cpp index 58d0362c4..9896ca539 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.cpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.cpp @@ -121,12 +121,11 @@ std::string const& FDv1AdapterSynchronizer::ConvertingDestination::Identity() // ----- FDv1AdapterSynchronizer ----- -FDv1AdapterSynchronizer::FDv1AdapterSynchronizer( - std::unique_ptr fdv1_source, - data_components::DataSourceStatusManager* status_manager) +FDv1AdapterSynchronizer::FDv1AdapterSynchronizer(SourceBuilder source_builder) : state_(std::make_shared(close_promise_.GetFuture())), destination_(std::make_unique(state_)), - status_manager_(status_manager), + status_manager_( + std::make_unique()), status_subscription_(status_manager_->OnDataSourceStatusChange( [state = state_](DataSourceStatus status) { auto error = status.LastError(); @@ -148,7 +147,7 @@ FDv1AdapterSynchronizer::FDv1AdapterSynchronizer( break; } })), - fdv1_source_(std::move(fdv1_source)) {} + fdv1_source_(source_builder(*status_manager_)) {} FDv1AdapterSynchronizer::~FDv1AdapterSynchronizer() { Close(); diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.hpp b/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.hpp index 8c0085cdf..b6e95a3ca 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.hpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.hpp @@ -9,6 +9,7 @@ #include #include +#include #include #include #include @@ -34,17 +35,17 @@ namespace launchdarkly::server_side::data_systems { class FDv1AdapterSynchronizer final : public data_interfaces::IFDv2Synchronizer { public: + using SourceBuilder = + std::function( + data_components::DataSourceStatusManager&)>; + /** - * @param fdv1_source The wrapped source. Must have been constructed - * with status_manager as its status sink so that - * state changes flow back into this adapter. - * @param status_manager Non-owning. The caller retains ownership and - * must keep it alive for the lifetime of the - * wrapped source and this adapter. + * @param source_builder Called once during construction with the + * adapter's status manager. Returns the wrapped + * FDv1 source, which must be constructed against + * the provided manager as its status sink. */ - FDv1AdapterSynchronizer( - std::unique_ptr fdv1_source, - data_components::DataSourceStatusManager* status_manager); + explicit FDv1AdapterSynchronizer(SourceBuilder source_builder); ~FDv1AdapterSynchronizer() override; @@ -111,10 +112,8 @@ class FDv1AdapterSynchronizer final std::shared_ptr const state_; std::unique_ptr const destination_; - // Non-owning. The caller must keep this alive for the lifetime of - // the wrapped source, which holds a reference to it for status - // reporting. - data_components::DataSourceStatusManager* const status_manager_; + std::unique_ptr const + status_manager_; std::unique_ptr const status_subscription_; std::unique_ptr const fdv1_source_; diff --git a/libs/server-sdk/tests/fdv1_adapter_synchronizer_test.cpp b/libs/server-sdk/tests/fdv1_adapter_synchronizer_test.cpp index da1408b94..39312d98e 100644 --- a/libs/server-sdk/tests/fdv1_adapter_synchronizer_test.cpp +++ b/libs/server-sdk/tests/fdv1_adapter_synchronizer_test.cpp @@ -47,41 +47,53 @@ class MockFDv1Source final : public IDataSynchronizer { bool bootstrap_was_null = false; }; +// Returns a SourceBuilder closure that constructs a MockFDv1Source. The +// resulting source and the adapter's internal status manager are exposed +// through the out parameters; pass nullptr for either to skip. +FDv1AdapterSynchronizer::SourceBuilder MakeMockBuilder( + MockFDv1Source** out_source = nullptr, + DataSourceStatusManager** out_sm = nullptr) { + return [out_source, out_sm](DataSourceStatusManager& sm) { + if (out_sm) { + *out_sm = &sm; + } + auto source = std::make_unique(sm); + if (out_source) { + *out_source = source.get(); + } + return source; + }; +} + } // namespace TEST(FDv1AdapterSynchronizerTest, FirstNextStartsFDv1Source) { - DataSourceStatusManager status_manager; - auto source = std::make_unique(status_manager); - auto* source_ptr = source.get(); - FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); + MockFDv1Source* source = nullptr; + FDv1AdapterSynchronizer adapter(MakeMockBuilder(&source)); auto future = adapter.Next(data_model::Selector{}); - EXPECT_EQ(1, source_ptr->start_count); - EXPECT_TRUE(source_ptr->bootstrap_was_null); + EXPECT_EQ(1, source->start_count); + EXPECT_TRUE(source->bootstrap_was_null); EXPECT_FALSE(future.IsFinished()); } TEST(FDv1AdapterSynchronizerTest, SecondNextDoesNotRestartSource) { - DataSourceStatusManager status_manager; - auto source = std::make_unique(status_manager); - auto* source_ptr = source.get(); - FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); + MockFDv1Source* source = nullptr; + FDv1AdapterSynchronizer adapter(MakeMockBuilder(&source)); auto first = adapter.Next(data_model::Selector{}); - source_ptr->destination_->Init(data_model::SDKDataSet{}); + source->destination_->Init(data_model::SDKDataSet{}); auto result = first.WaitForResult(1s); ASSERT_TRUE(result.has_value()); adapter.Next(data_model::Selector{}); - EXPECT_EQ(1, source_ptr->start_count); + EXPECT_EQ(1, source->start_count); } TEST(FDv1AdapterSynchronizerTest, FDv1InitProducesFullChangeSet) { - DataSourceStatusManager status_manager; - auto source = std::make_unique(status_manager); - auto* source_ptr = source.get(); - FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); + MockFDv1Source* source = nullptr; + FDv1AdapterSynchronizer adapter(MakeMockBuilder(&source)); auto future = adapter.Next(data_model::Selector{}); @@ -90,7 +102,7 @@ TEST(FDv1AdapterSynchronizerTest, FDv1InitProducesFullChangeSet) { flag.key = "flagA"; flag.version = 1; data_set.flags.emplace("flagA", data_model::FlagDescriptor(flag)); - source_ptr->destination_->Init(std::move(data_set)); + source->destination_->Init(std::move(data_set)); auto result = future.WaitForResult(1s); ASSERT_TRUE(result.has_value()); @@ -104,17 +116,15 @@ TEST(FDv1AdapterSynchronizerTest, FDv1InitProducesFullChangeSet) { } TEST(FDv1AdapterSynchronizerTest, FDv1UpsertProducesPartialChangeSet) { - DataSourceStatusManager status_manager; - auto source = std::make_unique(status_manager); - auto* source_ptr = source.get(); - FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); + MockFDv1Source* source = nullptr; + FDv1AdapterSynchronizer adapter(MakeMockBuilder(&source)); // Flag upsert. auto flag_future = adapter.Next(data_model::Selector{}); data_model::Flag flag; flag.key = "flagA"; flag.version = 2; - source_ptr->destination_->Upsert("flagA", data_model::FlagDescriptor(flag)); + source->destination_->Upsert("flagA", data_model::FlagDescriptor(flag)); auto flag_result = flag_future.WaitForResult(1s); ASSERT_TRUE(flag_result.has_value()); @@ -131,8 +141,7 @@ TEST(FDv1AdapterSynchronizerTest, FDv1UpsertProducesPartialChangeSet) { data_model::Segment seg; seg.key = "segA"; seg.version = 3; - source_ptr->destination_->Upsert("segA", - data_model::SegmentDescriptor(seg)); + source->destination_->Upsert("segA", data_model::SegmentDescriptor(seg)); auto seg_result = seg_future.WaitForResult(1s); ASSERT_TRUE(seg_result.has_value()); @@ -146,9 +155,7 @@ TEST(FDv1AdapterSynchronizerTest, FDv1UpsertProducesPartialChangeSet) { } TEST(FDv1AdapterSynchronizerTest, ClosePendingNextReturnsShutdown) { - DataSourceStatusManager status_manager; - auto source = std::make_unique(status_manager); - FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); + FDv1AdapterSynchronizer adapter(MakeMockBuilder()); auto future = adapter.Next(data_model::Selector{}); EXPECT_FALSE(future.IsFinished()); @@ -162,39 +169,33 @@ TEST(FDv1AdapterSynchronizerTest, ClosePendingNextReturnsShutdown) { } TEST(FDv1AdapterSynchronizerTest, CloseShutsDownStartedFDv1Source) { - DataSourceStatusManager status_manager; - auto source = std::make_unique(status_manager); - auto* source_ptr = source.get(); - FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); + MockFDv1Source* source = nullptr; + FDv1AdapterSynchronizer adapter(MakeMockBuilder(&source)); adapter.Next(data_model::Selector{}); adapter.Close(); - EXPECT_EQ(1, source_ptr->shutdown_count); + EXPECT_EQ(1, source->shutdown_count); } TEST(FDv1AdapterSynchronizerTest, CloseWithoutStartDoesNotShutDownFDv1Source) { - DataSourceStatusManager status_manager; - auto source = std::make_unique(status_manager); - auto* source_ptr = source.get(); - FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); + MockFDv1Source* source = nullptr; + FDv1AdapterSynchronizer adapter(MakeMockBuilder(&source)); // No Next() call — FDv1 source was never started. adapter.Close(); - EXPECT_EQ(0, source_ptr->start_count); - EXPECT_EQ(0, source_ptr->shutdown_count); + EXPECT_EQ(0, source->start_count); + EXPECT_EQ(0, source->shutdown_count); } TEST(FDv1AdapterSynchronizerTest, QueuedResultsDrainInFifoOrder) { - DataSourceStatusManager status_manager; - auto source = std::make_unique(status_manager); - auto* source_ptr = source.get(); - FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); + MockFDv1Source* source = nullptr; + FDv1AdapterSynchronizer adapter(MakeMockBuilder(&source)); // Start the source by satisfying one Next() with an Init. auto first = adapter.Next(data_model::Selector{}); - source_ptr->destination_->Init(data_model::SDKDataSet{}); + source->destination_->Init(data_model::SDKDataSet{}); first.WaitForResult(1s); // Two upserts queue with no Next() in flight. @@ -202,8 +203,8 @@ TEST(FDv1AdapterSynchronizerTest, QueuedResultsDrainInFifoOrder) { flag_a.key = "a"; data_model::Flag flag_b; flag_b.key = "b"; - source_ptr->destination_->Upsert("a", data_model::FlagDescriptor(flag_a)); - source_ptr->destination_->Upsert("b", data_model::FlagDescriptor(flag_b)); + source->destination_->Upsert("a", data_model::FlagDescriptor(flag_a)); + source->destination_->Upsert("b", data_model::FlagDescriptor(flag_b)); // Drain in FIFO order. auto r1 = adapter.Next(data_model::Selector{}).WaitForResult(1s); @@ -221,15 +222,14 @@ TEST(FDv1AdapterSynchronizerTest, QueuedResultsDrainInFifoOrder) { } TEST(FDv1AdapterSynchronizerTest, InterruptedStatusProducesInterruptedResult) { - DataSourceStatusManager status_manager; - auto source = std::make_unique(status_manager); - FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); + DataSourceStatusManager* source_manager = nullptr; + FDv1AdapterSynchronizer adapter(MakeMockBuilder(nullptr, &source_manager)); // kInterrupted from kInitializing stays kInitializing; drive past first. - status_manager.SetState(DataSourceStatus::DataSourceState::kValid); + source_manager->SetState(DataSourceStatus::DataSourceState::kValid); auto future = adapter.Next(data_model::Selector{}); - status_manager.SetState( + source_manager->SetState( DataSourceStatus::DataSourceState::kInterrupted, DataSourceStatus::ErrorInfo::ErrorKind::kNetworkError, "boom"); @@ -243,12 +243,11 @@ TEST(FDv1AdapterSynchronizerTest, InterruptedStatusProducesInterruptedResult) { } TEST(FDv1AdapterSynchronizerTest, OffStatusProducesTerminalErrorResult) { - DataSourceStatusManager status_manager; - auto source = std::make_unique(status_manager); - FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); + DataSourceStatusManager* source_manager = nullptr; + FDv1AdapterSynchronizer adapter(MakeMockBuilder(nullptr, &source_manager)); auto future = adapter.Next(data_model::Selector{}); - status_manager.SetState( + source_manager->SetState( DataSourceStatus::DataSourceState::kOff, DataSourceStatus::ErrorInfo::ErrorKind::kErrorResponse, "401"); @@ -262,9 +261,7 @@ TEST(FDv1AdapterSynchronizerTest, OffStatusProducesTerminalErrorResult) { } TEST(FDv1AdapterSynchronizerTest, NextAfterCloseReturnsShutdown) { - DataSourceStatusManager status_manager; - auto source = std::make_unique(status_manager); - FDv1AdapterSynchronizer adapter(std::move(source), &status_manager); + FDv1AdapterSynchronizer adapter(MakeMockBuilder()); adapter.Close(); auto future = adapter.Next(data_model::Selector{}); From 2f689336ff82b16eb86f67fa1d19b9c3dfe1ea3f Mon Sep 17 00:00:00 2001 From: Bee Klimt Date: Thu, 11 Jun 2026 22:27:20 -0700 Subject: [PATCH 17/17] fix: hold FDv1 source via shared_ptr and forward init-time errors --- .../fdv2/fdv1_adapter_synchronizer.cpp | 6 ++++-- .../fdv2/fdv1_adapter_synchronizer.hpp | 4 ++-- .../tests/fdv1_adapter_synchronizer_test.cpp | 21 ++++++++++++++++++- 3 files changed, 26 insertions(+), 5 deletions(-) diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.cpp b/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.cpp index 9896ca539..67bb98766 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.cpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.cpp @@ -134,16 +134,18 @@ FDv1AdapterSynchronizer::FDv1AdapterSynchronizer(SourceBuilder source_builder) } switch (status.State()) { case DataSourceState::kInterrupted: + case DataSourceState::kInitializing: + // Recoverable error. state->Notify(FDv2SourceResult{ FDv2SourceResult::Interrupted{*error}}); break; case DataSourceState::kOff: + // Terminal error. state->Notify(FDv2SourceResult{ FDv2SourceResult::TerminalError{*error}}); break; - case DataSourceState::kInitializing: case DataSourceState::kValid: - // No FDv2 result for these states. + // Recovery; no FDv2 result. break; } })), diff --git a/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.hpp b/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.hpp index b6e95a3ca..a382ff90a 100644 --- a/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.hpp +++ b/libs/server-sdk/src/data_systems/fdv2/fdv1_adapter_synchronizer.hpp @@ -36,7 +36,7 @@ class FDv1AdapterSynchronizer final : public data_interfaces::IFDv2Synchronizer { public: using SourceBuilder = - std::function( + std::function( data_components::DataSourceStatusManager&)>; /** @@ -116,7 +116,7 @@ class FDv1AdapterSynchronizer final status_manager_; std::unique_ptr const status_subscription_; - std::unique_ptr const fdv1_source_; + std::shared_ptr const fdv1_source_; // Serializes StartAsync and ShutdownAsync on fdv1_source_ across // concurrent Next() and Close() calls. diff --git a/libs/server-sdk/tests/fdv1_adapter_synchronizer_test.cpp b/libs/server-sdk/tests/fdv1_adapter_synchronizer_test.cpp index 39312d98e..26de674b6 100644 --- a/libs/server-sdk/tests/fdv1_adapter_synchronizer_test.cpp +++ b/libs/server-sdk/tests/fdv1_adapter_synchronizer_test.cpp @@ -57,7 +57,7 @@ FDv1AdapterSynchronizer::SourceBuilder MakeMockBuilder( if (out_sm) { *out_sm = &sm; } - auto source = std::make_unique(sm); + auto source = std::make_shared(sm); if (out_source) { *out_source = source.get(); } @@ -242,6 +242,25 @@ TEST(FDv1AdapterSynchronizerTest, InterruptedStatusProducesInterruptedResult) { interrupted->error.Kind()); } +TEST(FDv1AdapterSynchronizerTest, + InitializingWithErrorProducesInterruptedResult) { + DataSourceStatusManager* source_manager = nullptr; + FDv1AdapterSynchronizer adapter(MakeMockBuilder(nullptr, &source_manager)); + + auto future = adapter.Next(data_model::Selector{}); + source_manager->SetState( + DataSourceStatus::DataSourceState::kInterrupted, + DataSourceStatus::ErrorInfo::ErrorKind::kNetworkError, "boom"); + + auto result = future.WaitForResult(1s); + ASSERT_TRUE(result.has_value()); + auto* interrupted = + std::get_if(&result->value); + ASSERT_NE(interrupted, nullptr); + EXPECT_EQ(DataSourceStatus::ErrorInfo::ErrorKind::kNetworkError, + interrupted->error.Kind()); +} + TEST(FDv1AdapterSynchronizerTest, OffStatusProducesTerminalErrorResult) { DataSourceStatusManager* source_manager = nullptr; FDv1AdapterSynchronizer adapter(MakeMockBuilder(nullptr, &source_manager));