Configuration options for Kafka/RabbitMQ reconnect

[mark--]

The reconnect to Kafka works fine, but it is attempted with 'full speed' (about 10 per second on my machine). This behaviour should be configurable (for all binders). At least there should be a parameter for the intervall between two attempts and maybe some sort of backoff makes sense, too.

Furthermore, in the case of connection loss, an exception is logged. This should be replaced by dedicated logging.

[mbogoevici]

Thanks Mark,

Both these issues would need to be fixed via Spring Integration Kafka, and we will address them as part of upgrading to SI Kafka 2.0 (which should be fairly soon).

[mbogoevici]

@mark--

The reconnect frequency of the Kafka consumers to the brokers is set to 5 seconds, but I believe that the noise that you are currently seeing is caused by the Zookeeper client trying to reconnect. Are you stopping your Zookeeper ensemble as well ?

In the case of Zookeeper, the wait times on reconnect are random (between 0 and 1000ms) and I think that's what you see in the logs. Since that's just indicating that the client is trying to reconnect, I would suggest raising the logging levels to ERROR instead of WARN. We will set that by default in the client to avoid the noise.

[mbogoevici]

Closed via #556 in 6c4a271 and cherry-picked to 1.0.x branch.