fix(cache): make TTL.Load context-aware so callers can cancel while waiting#54
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jpugliesi wants to merge 7 commits into
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fix(cache): make TTL.Load context-aware so callers can cancel while waiting#54jpugliesi wants to merge 7 commits into
jpugliesi wants to merge 7 commits into
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…aiting The previous implementation blocked on <-promise.ready with no way to interrupt the wait. When multiple callers share an in-flight singleflight promise, a caller whose context is canceled had to wait for the fetch to complete before receiving an error. Replace the plain channel receive with a select over promise.ready and ctx.Done(). On cancellation the caller returns context.Cause(ctx) immediately; the in-flight goroutine continues to completion and stores the result in cache for future callers. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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- Bail out early (under the lock) if the caller's context is already canceled before starting a new fetch, preventing timed-out callers from triggering background provider I/O. - Use a double-select when ctx.Done() wins the race so a completed shared result is preferred over a simultaneous cancellation, avoiding flaky errors for co-waiters near their deadline. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
- TestTTLLoadAlreadyCanceledCacheMiss: verifies that Load with a pre-canceled context on a cache miss returns immediately without invoking fetch or populating the cache. - TestTTLLoadReadyBeatsCancel: stress-tests (1000 iterations, -race) the double-select by unblocking the fetch and canceling the co-waiter simultaneously, ensuring the only outcomes are success or context.Canceled and no other error is returned. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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Summary
TTL.Loadblocked on<-promise.readywith no way to interrupt the wait, so a caller whose context was canceled had to wait for the shared in-flight fetch to complete before receiving an errorselect { case <-promise.ready: ...; case <-ctx.Done(): ... }context.Cause(ctx)immediately; the in-flight goroutine continues to completion and stores the result for future callers — no goroutine leak, no cache poisoningTTL.Loadcall sites (cache.go,secret/cache.go,secret/authn/cache.go) to passctxas the new first parameterTest plan
go test ./cache/...passes, including newTestTTLLoadContextCancellationwhich verifies a co-waiter with a canceled context returns promptly while the fetch completes and is stored in cache🤖 Generated with Claude Code