Fix WebSocketClient.connect() hang when attempting to connect at an invalid websocket endpoint

[coudy]

I’ve been using the web socket client for a while and recently noticed that the session future doesn’t always complete on connect(). Specifically, this happens when I accidentally use ‘ws://' instead of ‘wss://', so the upgrade fails with my server responding with a 301 (and a Location rewritten to HTTPS). My code looks as follows:

var client = new WebSocketClient();
client.start();
var request = new ClientUpgradeRequest();
var sessionFuture = client.connect(delegate, serviceUri, request);
var session = sessionFuture.get();

I’d expect session to be isDone() and throw an ExecutionException. Instead, the blocking get hangs forever.

I can reproduce this on 9.4.12.RC2 from Maven Central.

[joakime]

I think I've been able to reproduce.

[joakime]

See PR #2902
Branch jetty-9.4.x-issue-2875-websocketclient-redirect has proposed fix.