iOS 5 and the initial handshake

t3chn0r commented 11 years ago

Not sure if this related to the crapy implementation of websockets in iOS 5 or some other quirk going on but sometimes it takes up to 3 tries for an iOS 5 device to connect to the websocket server.

iOS 6 has no problems at all but with iOS 5 I can see the client connecting to the server but as soon as it connects the session is closed and the onClose event is called. This happens 2 or 3 times until at some point the client connects and stays connected.

It appears something is going on during the intial handshake that iOS 5 or the Ratchet server don't like and the connection is closed instantly.

I'm not sure how to debug this... Is there any parameter in Ratchet to enable some kind of deep debugging information to see why the connection is being dropped?

Thanks for any help...

cboden commented 11 years ago

Could you post a gist with your php and javascript code please? I'll try to get my hands on an iOS5 device and test this weekend.

There aren't any debug tools you can just drop in. When I debug I'll usually write a class implementing MessageComponentInterface that spits out $connection information and stick that between where I think the problem is. I'll consider releasing a proper debug class in the future.

t3chn0r commented 11 years ago

Thanks @cboden, just created the following gist, if you have any question about anything please let me know.

Regards, t3ch

cboden commented 11 years ago

@t3chn0r - 2 hours in troubleshooting and I realized I grabbed an iOS4 device from work, oops!

I started with just raw JavaScript and my Fuzzing Test to replicate your issue, and have been adding components from your gist, testing each step of the way. I've gotten as far as using your JavaScript with jQuery.WebSocket without failure (and I have to step out for a few hours).

I have a few questions for you that I hope will help me replicate the issue:

Specifically what version of iOS 5 are you testing against?
Does the issue occur on the iOS Simulator or only the device? (I've downloaded the iOS 5.1 simulator to test)
Are you testing on a local machine, local network, or against a server on the internet? (I'm wondering if latency is causing a race condition)
Would you be able to provide me with the full repository of your project to test? If you don't want it to be public and are comfortable with me seeing it you could share it privately with me on BitBucket.

Finally, I forgot to mention earlier, this Logger is one of the tools I use for debugging (with bin example). The other, if you use it, is PHPStorm. It's ability to put break points on key points of Ratchet's source files and examen variables is amazing.

t3chn0r commented 11 years ago

Hello @cboden,

I'm using iOS 5.1.1, that's the last iOS 5 release I believe as the iPad reports that the software is up to date.
Device, I can test with an iOS simulator, which simulator did you get?
Testing with iPad device connecting to my development machine running Apache in Windows 7 and my development server running Apache in Linux/Debian (I see the same happening against both servers). All the connections are local, tested the same with iPad 3 running iOS 6 without any issues at all.
I can't provide the entire project but give me couple of days and I can create a mini-Symfony2 project an add the components related to WebSockets and try to duplicate the issue for sure.

I use PHPStorm so I will take a look at it... Haven't used debugging features yet.

Regards

t3chn0r commented 11 years ago

Just a quick update... I created a new Symfony2 project from scratch, added the command and the pusher files, and just added one page with the following code and I can see the issue happening with iOS 5.1.1:

<body>
    {% block body %}
    <div id="WebSocket_Status"></div>
    {% endblock %}

        <script>
        jQuery(function($) {
            "use strict";

            (function($, application, window) {
                application.WebSocketsClient = function() {
                    var ws = $.websocket( "ws://192.168.1.100:8000/", {
                        close: function() {
                            $("#WebSocket_Status").append("<p>Trying again in 10 seconds...</p>");

                            // Re-try connecting to the websocket server every 10 seconds
                            setTimeout( application.WebSocketsClient, 10000 );
                        },
                        open: function() {
                            $("#WebSocket_Status").append("<p>Connected...</p>");
                        },
                        message: function( e ) {
                                $("#WebSocket_Status").append("<p>Message received " + e.originalEvent.data + "...</p>");
                        }
                    });
                };
            })(jQuery, window.WST || (window.WST = {}), window);

            // Try to connect to our websocket server
            WST.WebSocketsClient();
        });
    </script>
</body>

cboden commented 11 years ago

Okie, I will re-test tonight after I'm done work. In the mean time can you test two things for me to help narrow it down please?

1) Can you test that Javascript with a plain CLI Ratchet test app (without symfony or ZMQ push); this will help me isolate where the problem is originating from.

2) I'm unable to obtain an iOS 5 device. Can you test on an iOS 5 simulator to verify the error will occur on a simulator as well as an actual iPad/iPhone -- this will ensure when I test on the simulator I will receive the same results you are.

To get a simulator (assuming you're on a Mac):

Download XCode (it's free) from the Mac App store
Create a new iOS project in XCode
Open XCode's preferences, select Downloads, then select Components
Click Install on the iOS 5.1 Simulator cell
When the install is done close the preferences window
The third button from the top left should let you select the iOS 5.1 simulator to run your project with; select it
Press the play (run) button to launch your app in the simulator
Once the simulator is running, press the home button, launch Safari and test your app

t3chn0r commented 11 years ago

Hello @cboden, sadly I don't have a Mac, I'll see if I can find an emulator for Windows 7...

Regarding the Ratchet test app without Symfony2, is there anything already out there that I can use or should I build something from scratch?

Regards, t3ch

cboden commented 11 years ago

If you checkout the Ratchet repository and run the following command:

php tests/AutobahnTestSuite/bin/fuzzingserver-stream.php

This will start a WebSocket server on port 8001 that will send back any message received to the client that sends it. Make sure you've run composer install first and that you run that command from the top repo directory.

I'll try looking for an iOS 5 device again. Cheers.

t3chn0r commented 11 years ago

Sorry for the wait... Was pretty busy the last few days. I started server per your instructions, I then created a small client code (attached) and then tested different devices.

On desktop, I tested Firefox, Chrome, Opera, and IE with no problems, all of them connected in the first try.
I then tested an iPod 4 and iPad 3 running iOS 6.1.3, again they all connected in the first try.
Last but not least, I tested an iPad 1 running iOS 5.1.1, it took 9 tries to connect and stay connected to the Ratchet server. The output from the client was:

Trying in 10 seconds... Trying in 10 seconds... Trying in 10 seconds... Trying in 10 seconds... Trying in 10 seconds... Trying in 10 seconds... Trying in 10 seconds... Trying in 10 seconds... Connected...

The client code that I used to test it was this:

<head>
    <meta charset="utf-8">

    <title>Websockets Test with iOS 5</title>
    <script src="js/jquery.js"></script>
    <script src="js/jquery.websocket.js"></script>
    <script src="js/json2.js"></script>
</head>

<body>
    <div id="WebSocket_Status"></div>

        <script>
        jQuery(function($) {
            "use strict";

            (function($, application, window) {
                application.WebSocketsClient = function() {
                    var ws = $.websocket( "ws://192.168.1.100:8001/", {
                        close: function() {
                            $("#WebSocket_Status").append("<p>Trying again in 10 seconds...</p>");

                            // Re-try connecting to the websocket server every 10 seconds
                            setTimeout( application.WebSocketsClient, 10000 );
                        },
                        open: function() {
                            $("#WebSocket_Status").append("<p>Connected...</p>");
                        },
                        message: function( e ) {
                                $("#WebSocket_Status").append("<p>Message received " + e.originalEvent.data + "...</p>");
                        }
                    });
                };
            })(jQuery, window.WST || (window.WST = {}), window);

            // Try to connect to our websocket server
            WST.WebSocketsClient();
        });
    </script>
</body>
</html>

If you need me to do some other tests please let me know.

Regards, t3chn0r

cboden commented 11 years ago

Excellent debugging info!

Can you update your HTML using these remote Javascript files and verify the error still occurs and ensure we're testing against the same versions:

<script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
<script src="https://raw.github.com/dchelimsky/jquery-websocket/v0.0.4/jquery.websocket.js"></script>
<script src="https://raw.github.com/douglascrockford/JSON-js/master/json2.js"></script>

I tested your script (with the above changes) against my fuzzing server using PHP 5.4.6 on Ubuntu 12.10 64bit and was still unable to replicate your error. I've run into the rare scenario developing for iOS where everything works on the simulator but when once on the hardware it acts differently.

Since I'm unable to obtain an iPad 1 with iOS 5 I think we should collaborate offline; I'd like to setup a the above server with some logging and have you hit my server with your iPad so I can see what Ratchet is doing while you receive the error. Please add me on gChat or come see me on IRC and we'll work out a time to solve this issue.

t3chn0r commented 11 years ago

I'm using those versions but I went ahead anyway and change the index.html to use those scrips instead of the local ones. I ran 3 tests in total:

1: connected in the 4th attemp. 2: connected in the 5th attemp. 3: connected in the 4th attemp.

No problem helping you with this. Not sure how to add you to Google Chat as I don't have your email. :)

cboden commented 11 years ago

My email is in Ratchet's composer.json file. I'll start setting up a server.

cboden commented 11 years ago

Was finally able to replicate the issue on iOS simulator with help from @t3chn0r

The Hixie protocol provides little/no information when errors occur; best I can tell right now is Ratchet is completing the upgrade handshake, telling its decorated component onOpen and then iOS closes the connection at the socket layer. I'm going to try to flesh out the Hixie unit tests a little more to see if I can replicate the protocol without a wire.

Here is a handshake request that failed (values were base64 encoded to be copy/paste'able):

Sec-WebSocket-Key1: QTN+ICszNiA2IDJvICBWOG4gNyAgc08yODhZ
Sec-WebSocket-Key2: TzEyICAgeVsgIFFSNDUgM1IgLiAyOFggNC00dn4z
Body Code: 6dW+XgKfWV0=

ping @mikealmond

cboden commented 11 years ago

I believe I finally found the underlying issue. I was finally able to replicate the issue on a simulator because of the infrastructure used; to test with @t3chn0r I setup a Ratchet server on my home network (slow upload speed) to gather debug information. Because the network connection was so slow TCP fragmented the messages, which is usually fine. However, the Hixie76 protocol uses a body length of 8 bytes and the HttpRequestParser looks for 2 CRLF's, which happens to be when the headers are received, but not the body. It then tells Ratchet the message is received, while it is in fact not.

I'll try to put some code in to the Hixie76 parser to trigger an underflow message, telling the HttpRequestParser to keep building the message.

t3chn0r commented 11 years ago

Good catch Chris, glad I could help, although I did almost nothing... lol! :+1: :+1:

cboden commented 11 years ago

Apparently that was only part of the problem. I've confirmed Ratchet is now always receiving the challenge body but some connections are still failing on the client.

@t3chn0r Can you re-test with the new dev-hixie-testing branch on Safari 5 and send me the header info on a failing request please?

ratchetphp / Ratchet

iOS 5 and the initial handshake #80