ARTEMIS-5890 AMQP LargeMessage writer should check connection state on the WriterThread

[clebertsuconic]

…

[tabish121]

The code actually already has several checks for closed state related to the sender but in reality even this is not a guarantee that you won't see this error as the proton code was not meant to be used outside the thread that manages the engine so the visibility of these values is not ensured to be updated in this delivering thread.

[clebertsuconic]

What happens is this:

• there's a pending task in the executor to deliver the large message.
• before the deliver happens, an onRemoteClose is called:
  **

  artemis/artemis-protocols/artemis-amqp-protocol/src/main/java/org/apache/activemq/artemis/protocol/amqp/proton/AMQPConnectionContext.java

  Lines 839 to 850 in db04425

  	handler.requireHandler();
  	connection.close();
  	connection.free();
  	for (AMQPSessionContext protonSession : sessions.values()) {
  	protonSession.close();
  	}
  	sessions.clear();
  	// We must force write the channel before we actually destroy the connection
  	handler.flushBytes();
  	destroy();

• The Writer is not closed, when the task reaches the execution point the Link will have some invalid state.

We need to check the isClosed from the session / connection / link somehow. or we need to make the onRemoteClose to also close the Writer.

[clebertsuconic]

I just amended to another possible fix..

[clebertsuconic]

BTW: The thread being used here is the netty thread, as this is started with connection.runLater calls. so this is in the same thread.

[clebertsuconic]

there are a few important comments added on https://issues.apache.org/jira/browse/ARTEMIS-5890

[tabish121]

I've pushed a branch that simplifies the changes and accounts for the various paths that are triggering WARN logging which reduces the amount of change here. While the checks for the connection state were actually thread safe they don't account for all the ways this could hit closed states.

https://github.com/tabish121/artemis/pull/new/ARTEMIS-5890

Have a look