Lack of timeout/retry + lost disposition = disaster

[BertKleewein]

While hunting down a bug, I discovered that rhea does not handle lost dispositions very well. Because of how CircularBuffer in session.js is written, if a single disposition fails to arrive, Outgoing.deliveries will eventually fill up. As a result, somewhere down the line, about 2047 transfers later, the customer app will no longer be able to send.

I'm willing to work with you on a fix, but I'm really more of an MQTT guy, so I'm not sure what the right behavior should be.

[ra-dave]

I think we are currently experiencing this issue with the Azure IoT Node.js SDK (which uses rhea) When using Edge runtime messages stop flowing to IoT Hub after 2047. Oddly though there is no problem if we connect directly to IoT Hub.

@BertKleewein Could you post the code snippet that you think the problem is? I'm guessing it's in session.js?