fix(cloudflare): Use TransformStream to keep track of streams#20452
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fix(cloudflare): Use TransformStream to keep track of streams#20452
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logaretm
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Way cleaner, that's very cool!
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closes #20409
closes JS-2233
Problem
The issue is that we had a
waitUntil?.(streamMonitor);that waited until the stream was done.streamMonitorcould potentially live forever, whilewaitUntilhas a limit of 30 seconds until it is getting cancelled. With the current approach we allow streams only being open for 30 seconds - then thewaitUntilwould cancel the request. This can only be reproduced when deployed, that is the reason why we didn't notice in our test cases.Solution
By removing the
waitUntilthere is no hard limit, but we still have to wait until the stream is over in order to end our spans and flush accordingly. This can be achieved with TransformStream, where we simply use the stream body from the client and pipe it through our transformer. Withflushandcancelwe know exactly when the stream would end or be cancelled - which is the only thing we need.There is btw no reason to add integration of E2E tests, as
miniflaredoesn't have this limitation and it couldn't be reproduced, so the tests would always succeed. The unit tests are kinda simulating that by checking ifwaitUntilis getting called or not.I also figured that the client isn't getting disposed and would leak memory - this PR is also fixing that (see screenshots).
Some evidence
repro: https://github.com/JPeer264/sentry-repros/tree/issue-20409
cloudflare logs before:
cloudflare logs after:
Sentry trace: https://sentry-sdks.sentry.io/explore/traces/trace/29a307b1272e48dbb3a87c270c487e5a/