Configure Apache 2.4.7 for proxying socket.io

Question

On our server we are running Apache already on port 80, on this same server I want to serve socket.io and I would like to connect to the socket.io server also on port 80. So I tried to get Apache to proxy port 80. I found this stackoverflow entry: https://serverfault.com/questions/616370/configuring-apache-2-4-mod-proxy-wstunnel-for-socket-io-1-0

What I did:

I enabled the next modules in apache:

a2enmod rewrite proxy proxy_wstunnel

I created a new site in '/etc/apache2/sites-available/mysite.conf', with the next content:

<VirtualHost subdomain.mydomain.com:80>
    Servername subdomain.mydomain.com

    RewriteEngine On
    RewriteCond %{REQUEST_URI}  ^/socket.io            [NC]
    RewriteCond %{QUERY_STRING} transport=websocket    [NC]
    RewriteRule /(.*)           ws://localhost:3001/$1 [P,L]

    ProxyPass        /socket.io http://localhost:3001/socket.io
    ProxyPassReverse /socket.io http://localhost:3001/socket.io
</VirtualHost>

On the same server I have the socket.io server running on port 3001:

server.listen('3001', function(){
  console.log('Socket.io server listening on *:3001');
});


io.listen(server).on('connection', function(client) {
    // Rest of the code
}

And the socket.io clients are connecting on this subdomain configured into apache:

var socket = io.connect('http://subdomain.mydomain.com/', {query: {extra_info : extra_info}});

Once I startup a client. I don't see anything coming into the socket.io server logging (I have added a lot of console.log() entries. All I see in the console of the client is the next error:

GET http://subdomain.mydomain.com:8100/socket.io/?extra_info=fe4567&EIO=3&transport=polling&t=1416987210079-31 net::ERR_CONNECTION_TIMED_OUT

If I connect the clients directly to port 3001 of the socket.io server http://subdomain.mydomain.com:3001 all is just working fine (when I open port 3001 on the apache server).

I am running the next versions:

• Apache: 2.4.7
• Socket.io server & client: 1.2.1

---

EDIT:

When I change the connection URL in var socket = io.connect('http://subdomain.mydomain.com/', {query: {extra_info : extra_info}}); to http://subdomain.mydomain.com:80.

I receive a different error:

GET http://subdomain.mydomain.com/socket.io/?user_id=2&EIO=3&transport=polling&t=1418122378582-40 
(index):1 XMLHttpRequest cannot load http://subdomain.mydomain.com/socket.io/?extra_info=sdferr&EIO=3&transport=polling&t=1418122378582-40. No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://192.168.178.158:8100' is therefore not allowed access. The response had HTTP status code 500.

I though setting the Access-Control-Allow-Origin header in Apache would solve the issue, but it doesn't. I have added this to the file /etc/apache2/sites-available/mysite.conf:

Header set Access-Control-Allow-Origin "*"

Answer 1

based on our comments, here is some thing you may try, not for sure.

not sure how to pass both port and extra_info query, but the idea is to set port.

io.connect('http://subdomain.mydomain.com/', {port: 80})

or this

io.connect('http://subdomain.mydomain.com:80/', {query: {extra_info : extra_info}})

good luck.

Answer 2

There where 2 things going wrong. First of all, you need to specify port 80 in the client to be able to connect to port 80. So I configured the client to connect as follows:

io.connect('http://subdomain.mydomain.com:80/', {query: {extra_info : extra_info}})

After this change you will get several CORS issues. The only thing I needed to change is how the client JS file is retrieved. In my AngularJS application I included the socket.io client JS file as follows:

<script src="https://cdn.socket.io/socket.io-1.2.1.js"></script>

I needed to change this to:

<script src="http://subdomain.mydomain.com/socket.io/socket.io.js"></script>

It seems that the socket.io client is also served automatically by your socket.io server. If you retrieve the client JS from your own server you will get no CORS issues.