Recursive call in Pushsubscription leads to stack overflow

[segfaultdoc]

While using the Watch client to subscribe to new msgs I would notice that one of our threads would overflow its stack. This was specific to a bucket and wouldn’t happen with the other bucket Watches. After some digging I found this recursive call:
https://github.com/nats-io/nats.rs/blob/main/nats/src/jetstream/push_subscription.rs#L133

The reason why it happened with one of our buckets was due to the entry write/remove cadence, every few days as opposed to the other buckets being every few seconds. This means the call recurses on every heartbeat msg (5000ms) until it overflows its stack or an entry is modified/removed.

Although the function looks tail call optimized, rust does not guarantee TCO.

Next steps, we’ll fork and make a PR upstream that removes this recursive call.

[Jarema]

@segfaultdoc thanks for reporting that.

Did I understand correctly, that you want to contribute and fix this issue?

[segfaultdoc]

@segfaultdoc thanks for reporting that.

Did I understand correctly, that you want to contribute and fix this issue?

correct just created a PR into main: #448

[Jarema]

fixed by #448