2.x: UnicastSubject fix for the child becoming visible before onSubscribe is called. #3381
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
onSubscribe is called.
|
Closing, will be included in the complete backport PR. |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Discovered while the test
NbpOperatorConcatTest.testIssue2890NoStackoverflowhung on Travis.What happened is that the reference to the child became visible before the call to its
onSubscribemethod so a concurrent source emitting at the exact same time could already see the "unstarted" child. The PR fixes this in bothNbpUnicastSubjectandUnicastSubjectby changing the order of calls. The rest of the subjects behave correctly (callonSubscribefirst, make child visible second).In addition,
UnicastSubjectnow callsdrain()because when theonSubscribecallsrequestanddrain, the child is not visible and nothing gets replayed. Once bothonSubscribecall returns and the child is becomes visible, a call todrainagain will now correctly replay all available contents that were requested.