fix: feign RepeatedCollectManager depth leak causing record miss (#587)#622
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zwobill merged 1 commit intoJul 16, 2026
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…xtest#587) onEnter unconditionally called RepeatedCollectManager.enter() but onExit skipped exitAndValidate() when a mock result was returned, so CallDepth kept growing across replay-hit requests. Once depth passed 1, subsequent record attempts on the same thread saw exitAndValidate()==false and were silently dropped (issue arextest#587 reports depth reaching 9 while normal is 4). - move outermost check (validate()) before enter() so nested http clients (e.g. Feign -> Apache) skip inner replay and avoid request body double consumption - call exitAndValidate() unconditionally in onExit to keep enter/exit balanced regardless of mock hit - update tests to cover the nested-call skip path
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Summary
Fix #587 — under mixed record/replay traffic on the same thread, some requests silently fail to record (issue reports ~10% failure rate; user observed
CallDepthreaching 9 while a normal call chain tops out at 4). Root cause is unbalancedRepeatedCollectManager.enter()/exitAndValidate()in the Feign advice.Root cause
In
FeignClientInstrumentation.ExecuteAdvice:onEntercallsRepeatedCollectManager.enter()unconditionally whenneedRecordOrReplay()onExitreturns early inside themockResult != null && notIgnoreMockResult()branch, without callingexitAndValidate()Every replay-hit request therefore leaks
+1on the thread-localCallDepth. Once depth passes 1, subsequent record attempts on the same thread seeexitAndValidate() == falseand are dropped. This explains the "10% requests not recorded / depth up to 9" symptom in the issue.There's also a latent bug in the same code path: nested http clients (e.g. Feign wrapping Apache HttpClient via
feign-httpclient) both try to replay, and the inner client re-consumes the request body — leading to replay-match misses.Changes
FeignClientInstrumentation.java:enter()— captureboolean isOutermost = RepeatedCollectManager.validate()first, so a nested call detects it's inside an already-entered scope and skips its own replay.isOutermost— inner nested clients no longer double-consume the request body.exitAndValidate()called unconditionally at top ofonExit— mock hits now decrementCallDepthtoo, keeping enter/exit balanced. The savedisOutermostis used for the record gate.FeignClientInstrumentationTest.java:RepeatedCollectManager.validate()in the existing replay-path assertionTest plan
mvn -pl arex-instrumentation/httpclient/arex-httpclient-feign test— 12/12 pass