flags

Summary Adds and support to allow the server to skip streaming the initial datafile contents if it matches the bundled revision Replaces the monolithic with a Controller state machine backed by dedicated , , and I/O modules Tags all data with its origin at arrival (, , , , ), flowing into a new field (, , ) Enforces mutually exclusive streaming and polling — never runs both simultaneously Adds a guard that rejects stale data from overwriting newer in-memory state Hardens stream reconnection: 401s now fast-fail (no waiting for timeout), a minimum 1s gap between attempts prevents server spam, and headers aid debugging Moves per-request deduplication from a global to per-instance, so multiple calls no longer share tracking state Adds requeue-on-failure to — failed ingest events are prepended back to the queue (capped at 500) instead of silently dropped Deduplicates build-step reads: all concurrent calls during a build share a single fetch promise and emit a single usage tracking event Adds ReDoS protection (10k char limit on regex comparator inputs) and circular environment-reuse detection in evaluation Rewrites the entire test suite as black-box tests through the public API using and , removing the dependency Breaking Changes Renamed exports (old names preserved as deprecated aliases): class → (alias kept) type → (alias kept) interface → (no alias — this was the lower-level interface, not the re-exported one) Since and are still exported with annotations, consumers using those names won't break. However, was renamed to without an alias — anyone importing from types will break. is now required on all evaluation results: Added to the type Any code that constructs or pattern-matches objects exhaustively would need updating no longer throws when all data sources fail (if is provided): On : calls without try/catch — if read throws, the error propagates On : wraps in try/catch and returns when a default is provided This is a behavioral change — callers that relied on catching errors from when sources are down will now silently get the default value back now reports on FLAG_NOT_FOUND: On : no call when the flag definition is missing On : calls with when exists initialization failures are swallowed: On : does — init errors propagate On : wraps in try/catch — init errors are swallowed, letting handle its own fallback chain Error message prefix changed: → → → ControllerControllerOptionsMetrics.mode'streaming' \ 'offline'ControllerInterfaceDataSourcegetDatafile()createClientsdkKeyOrConnectionStringDataSourceControllerInterfaceclient-map.tsClientInstanceclientMapControllerInstancecontrollerInstanceMapcontroller-fns.tsdata-source/FlagNetworkDataSourceInMemoryDataSourcestream-connectioncontroller/mswfetchMockFlagNetworkDataSourceControllerFlagNetworkDataSourceOptionsControllerOptions