fix(flask): handle missing segment gracefully in after_request - #492
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reginaldalfret wants to merge 1 commit into
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reginaldalfret wants to merge 1 commit into
reginaldalfret wants to merge 1 commit into
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When an earlier Flask before_request extension short-circuits or raises, X-Ray before_request might not create a segment. Guard _after_request to return the response gracefully when no segment is open, matching the pattern in _teardown_request. Fixes aws#405
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Description
When Flask executes
before_requestfunctions, if an earlier extension raises an exception or returns a response early, subsequentbefore_requestcallbacks (including X-Ray's) are skipped, whileafter_requestcallbacks are still executed.In
XRayMiddleware._after_request,segment.put_http_meta(...)previously assumed thatcurrent_segment()orcurrent_subsegment()is always present, raisingAttributeError: 'NoneType' object has no attribute 'put_http_meta'when no segment is open.This PR adds a
try...except... if not segment: return responsecheck in_after_request, matching the existing guard pattern in_teardown_request, so un-traced or early-terminated responses are safely returned without crashing.Testing
test_missing_segment_in_after_requestintests/ext/flask/test_flask.pyconfirming earlybefore_requestresponses are handled without error.Fixes #405