The http server delegates the incoming requests to a separate thread pool
where some blocking tasks get executed (i.e. JDBC calls) as we do not want
to block netty I/O threads.
The thread pool (actually a java.util.concurrent.ThreadPoolExecutor instance)
has an internal queue where the requests are queued before execution. In this way
we can deal with some short time request bursts.
The queue can be bounded so if the queue capacity is reached the
subsequent requests are rejected. This way we can protect our server from
overloading.
The server receives and processes five messages from the client and then
disconnects it. If the server is not available the client retries the
connection (using Mono.retryBackoff).
I'm still figuring out how to reconnect automatically on server disconnect
without creating a separate TcpClient just for that.