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Wez Furlong
2b1146aa91
There is a potential race between the timerwheel tick and bulk queue operations (flushing, bouncing). The logic in the tick case has some accommodations for this, but there is another outstanding that can result in racing to manage the metadata load state on a message. In the tick case, we load it if needed, then resolve the queue name, so that we can resolve the Queue handle. We need the queue handle to decide whether we are responsible for the message, or whether we might be racing with a concurrent action. In the race case, the other actor may have decided to release the message metadata, which will cause the queue name resolution to fail. While we could just shrug and silently ignore the error in that case, that makes me uneasy. What this commit does is adjust the v1 wheel entry so that we capture weak references to both the message and its containing queue. Then when we tick, we can simply upgrade both of those and reconcile without needing to manipulate any message metadata. These changes unfortunately result in re-duplication of some of the logic that I recently refactored to be shared with the v2 tick implementation. The v2 tick implementation has the same edge case around metadata, but cannot be easily adjusted to use the same pattern. So this commit sticks a comment in the code; nobody is using v2 AFAIK, and there have been reports of some wonky behavior with it. My recommendation at this time is to avoid using the v2 wheel and we can fix this all up for it later.