Graceful termination of socket connections to the RTI

[byeonggiljun]

No description provided.

[lhstrh]

Have you been able to confirm that this addresses the non-deterministic failure we've been seeing?

[byeonggiljun]

@lhstrh As a federate destroys the socket connection right after sending LTC and Resign signals, the RTI potentially misses those signals. Thus, I propose using socket.end() instead of socket.destroy() so that the buffer is flushed before terminating. However, as both socket.write() and socket.end() are asynchronous, I guess socket.end() may close the connection before socket.write() writes any message to the buffer.

reactor-ts/src/core/federation.ts

Lines 1449 to 1454 in d028653

	protected _finish(): void {
	this.sendRTILogicalTimeComplete(this.util.getCurrentTag());
	this.sendRTIResign();
	this.shutdownRTIClient();
	super._finish();
	}

To completely mitigate this, we have to manage a buffer ourselves to track pending network messages that need to be sent. But this PR makes it much better than master and works fine in most cases.

[lhstrh]

Cool! It might make sense to document your analysis in an issue, should the problem resurface.

[byeonggiljun]

Cool! It might make sense to document your analysis in an issue, should the problem resurface.

I created the issue #303!