Fix race condition in websocket unsubscribe/resubscribe #2855
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- If the app tries to start a new websocket subscription before the last one was properly unsubscribed, the app will return a flow that is null and crash. To prevent this, change the unsubscribe logic to immediately remove the subscription ID - the confirmation isn't used. This will allow the app to start a new subscription and create a new flow even if the previous unsubscribe hasn't yet fully finished (which is OK).
dshokouhi
approved these changes
Sep 5, 2022
JBassett
approved these changes
Sep 5, 2022
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Summary
If the app tried to start a new websocket subscription before the last one with the same message/data was properly unsubscribed, the app would return a flow that is
nulland crash. To prevent this, change the unsubscribe logic to immediately remove the subscription ID (the confirmation isn't used). This will allow the app to start a new subscription and create a new flow even if the previous unsubscribe hasn't yet fully finished.More info and reproduction steps in the original issue, which this PR fixes: #2852
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