FastAPI: emit structured RequestHandled event per HTTP request - #202
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Adds RequestLifecycleMiddleware to the FastAPI integration, registered automatically by FastAPIProvider. For every request it fires a RequestHandled event (method, path, status_code, duration_ms, request_id) through the existing Event dispatcher/facade — no new event mechanism, no storage, no UI. A request id is generated per request (or echoed back if the client already sent one) and returned via the X-Request-Id header.
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A bare (non-HTTPException) exception is handled by Starlette's ServerErrorMiddleware, which sits outside RequestLifecycleMiddleware — so the middleware's local response stays None on that path and the header never gets set there. HTTPException stays inside the middleware via ExceptionMiddleware and was already fine. Stamp the header from the shared exception handler instead (covers Exception, HTTPException, and RequestValidationError alike), using the request_id RequestLifecycleMiddleware already stashed on request.state before the route ran. This keeps the RequestHandled event's request_id correlated with the response the client actually receives, including on the 500 path.
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Summary
Implements task #1324 — Telescope-style visibility into FastAPI requests, scoped down to structured events only (no storage, no UI, no other watchers).
RequestLifecycleMiddleware(fastapi_startkit/fastapi/middleware.py), registered automatically byFastAPIProvider.boot().RequestHandledevent (fastapi_startkit/fastapi/events.py) through the existing Event dispatcher/facade from task #940 — no parallel event mechanism was built.method,path,status_code,duration_ms,request_id.uuid4), or echoed back if the client already sent anX-Request-Idheader. The id is also returned on the response viaX-Request-Id.Event.listen(RequestHandled, ...).try/finallyso the event still fires (withstatus_code=500) even if an unhandled exception escapes the router.Scope confirmation / overlap check
on_event("startup"/"shutdown")/lifespan hooks (Application.add_event_handler), not per-request events. No overlap.RequestHandledevent via the Event dispatcher. Worth closing/merging #1262 into this PR's context.Out of scope (left as extension points, not implemented)
Test plan
tests/fastapi/test_request_lifecycle_events.py: boots a realApplication+FastAPIProvider, hits real routes viaTestClient, and asserts the event payload, theX-Request-Idheader (generated + echoed), error-status propagation, andEvent.fake()interception.uv run pytest --ignore=tests/masoniteorm/postgres→ 2046 passed, 7 skipped.ruff check/ruff format --checkclean.