otel_bloc 0.2.0

OpenTelemetry instrumentation for `package:bloc`. A `BlocObserver` emitting spans on every bloc event, state change and error, turning traces into a state-machine timeline.

Changelog

All notable changes to this project will be documented in this file.

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

0.2.0 - 2026-08-08

Changed

• Dependency floors raised to dartastic_opentelemetry ^1.1.0-beta.12 and dartastic_opentelemetry_api ^1.0.0-rc.1. The previous floors declared compatibility with API versions that predate the semconv enums this package uses and could not actually resolve-and-compile.
• repository URL corrected to the canonical Dartastic org casing so pub.dev repository verification succeeds.

Renamed

• Ships as otel_bloc, the pure-Dart core, matching the core/overlay pattern. The package only ever depended on bloc (the pure-Dart core that flutter_bloc re-exports), so it works for both bloc and flutter_bloc apps. A slim Flutter overlay ships separately as otel_flutter_bloc for flutter_bloc-based apps.

Added

• OTelBlocObserver — a BlocObserver that emits one short span per Bloc/Cubit lifecycle event (onCreate, onTransition for Bloc, onChange for Cubit, onError, onClose). Each span carries the bloc.* semconv attributes (bloc name + kind, event type, state before/after).
• onChange is suppressed for Blocs because onTransition fires immediately after it with strictly more info. Cubits get their own onChange spans since they don't go through events.
• onError is recorded via recordException then setStatus(Error), in OTel-spec order.
• BlocSemantics — typed attribute-key enum implementing OTelSemantic, package-local because OTel has no upstream semantic convention for state-machine frameworks yet.
• Constructor flags: recordLifecycle (default true), recordTransitions (default true), recordEventValues (default false), recordStateValues (default false), valueAttributeMaxLength (default 256).
• Targets bloc: ^9.0.0. Works with both flutter_bloc apps (which re-export bloc) and pure-Dart bloc apps.
• 6 unit tests covering: Bloc add → onCreate + onTransition + onClose (with onChange correctly suppressed), Cubit emit → onChange (with onTransition correctly absent), onError → Error status + exception event, recordEventValues + recordStateValues clipping, recordLifecycle false, recordTransitions false.
• 1 optional integration test verifies the OTLP export round-trip against a local trace backend; it self-skips when no local stack is reachable.
• Runnable example/main.dart drives a bloc through an event inside an active parent span so the transition spans nest under it.