jersey-netty-connector Intermittent Stuck eventLoop/ExecuterService threads if Request failed in writeEntity(executed in pool threads) under load

[sumitaneja]

NettyConnector doesn't blcoks eventLoops threads and eventually ExecutorServiceThreads under stress if writeEntity(executed in pool threads) fails/throw error for some reason.

We noticed this happening in two cases

1. Malformed request (say content type is multipart and no body part is present). Request Errors out with illegal argument exception.
2. We are sending large binary payload and target system returns 413. Occasionally there are BuffereOverflow and Stream Closed Exceptions too.

Issue identified in below code with NettyConnector

jersey/connectors/netty-connector/src/main/java/org/glassfish/jersey/netty/connector/NettyConnector.java

Lines 473 to 509 in d9658aa

	executorService.execute(new Runnable() {
	@Override
	public void run() {
	// close listener is not needed any more.
	ch.closeFuture().removeListener(closeListener);
	try {
	jerseyRequest.writeEntity();
	if (entityWriter.getType() == NettyEntityWriter.Type.DELAYED) {
	nettyRequest.headers().set(HttpHeaderNames.CONTENT_LENGTH, entityWriter.getLength());
	contentLengthSet.countDown();
	}
	} catch (IOException e) {
	responseDone.completeExceptionally(e);
	}
	}
	});
	headersSet.await();
	if (!expect100ContinueHandler.isExpected()) {
	// Send the HTTP request. Expect:100-continue processing is not applicable
	// in this case.
	entityWriter.writeAndFlush(nettyRequest);
	}
	if (HttpUtil.isTransferEncodingChunked(nettyRequest)) {
	entityWriter.write(new HttpChunkedInput(entityWriter.getChunkedInput()));
	} else {
	entityWriter.write(entityWriter.getChunkedInput());
	}
	if (entityWriter.getType() == NettyEntityWriter.Type.DELAYED) {
	contentLengthSet.await();
	}
	entityWriter.flush();

Our analysis shows this to be timing issue in case of error. I.e Line 509 [entityWriter.flush();] executes before 488 [responseDone.completeExceptionally(e);]. (issue can be recreated without stress by putting a simple sleep before 488)

Issue:
Line 509 starts task in nioEventloopGroup which tries to read chunks. This goes on till Channel is writable and pendingMessage is Chunked Input.
See https://github.com/netty/netty/blob/4.1/handler/src/main/java/io/netty/handler/stream/ChunkedWriteHandler.java#L225-269

Once it goes in loop to read chunks, exception in doesnt signal this loop to break.

Possible fix in Netty Connector
close chunked input in NettyConnector on exception at line 488

Sample code fix
}catch (Throwable e){
if(entityWriter.getChunkedInput()!=null){
try {
System.out.println(" CLOSING CHUNKED");
entityWriter.getChunkedInput().close();
} catch (Exception ex) {
System.out.println("ERROR CLOSING CHUNKED");
}
}
responseDone.completeExceptionally(e);
}

[sumitaneja]

Attached reproducer with suggested code fix in Netty connector. (NettyConnector is part of the

JerseyNetty.zip

zip)