Apache2 WebSockets reverse proxy on same URL

Question

How to configure Apache2 to proxy WebSocket connection (BrowserSync for example), if it's made on the same URL, with only difference being header "Upgrade: websocket" and URL schema ws://?

For example:

HTTP request:
GET http://example.com/browser-sync/socket.io/?... HTTP/1.1
...

WebSocket request:
GET ws://example.com/browser-sync/socket.io/?... HTTP/1.1
Connection: upgrade
Upgrade: websocket
Sec-WebSocket-Version: 13
...

All examples I find, redirect some path only, like "<Location /ws>..." or "ProxyPass /ws/ ws://example.com/"

My current config:

ProxyRequests off
<Location />
    ProxyPass http://127.0.0.1:3000/
    ProxyPassReverse /
</Location>

mod_proxy, mod_proxy_http and mod_proxy_wstunnel are enabled.

score 45 · Accepted Answer · edited Apr 13 '17 at 12:13

45

Answering myself.

Using RewriteEngine, hint given by this post, and WebSocket handshake specification:

RewriteEngine On
RewriteCond %{HTTP:Connection} Upgrade [NC]
RewriteCond %{HTTP:Upgrade} websocket [NC]
RewriteRule /(.*) ws://127.0.0.1:3000/$1 [P,L]

ProxyRequests off
<Location />
    ProxyPass http://127.0.0.1:3000/
    ProxyPassReverse /
</Location>

edited Apr 13 '17 at 12:13

Community

1
1

answered Apr 23 '15 at 12:37

metalim

1,479
1
12
22

2

Thank you so much! – Sérgio Reis Sep 29 '17 at 14:40
1

Great, was looking for this and will definitely try this one. – Vipin Jain Jan 28 '19 at 14:33
Helped me a lot - didn't think turning ProxyRequests to off would do the trick, but that ended up being the case. Thanks! – Permanently Feb 16 '21 at 01:57

score 6 · Answer 2 · answered Feb 07 '18 at 14:51

Thanks a lot to metalim! I publish the full configuration here for reference:

<VirtualHost *>
    ServerName example.org
    ServerAlias *.example.org
    ServerAdmin sysadmin@example.org
    ProxyRequests Off
    ProxyPreserveHost On

    RewriteEngine On
    RewriteCond %{HTTP:Connection} Upgrade [NC]
    RewriteCond %{HTTP:Upgrade} websocket [NC]
    RewriteRule /(.*) ws://192.168.1.1/$1  [P,L]

    ProxyPass / http://192.168.1.1/ retry=1
    ProxyPassReverse / http://192.168.1.1/

    ErrorLog /var/log/apache2/example.org.error.log
    CustomLog /var/log/apache2/example.org.access.log combined
</VirtualHost>

score 1 · Answer 3 · answered Aug 17 '23 at 12:21

1

Since Apache httpd 2.4.47, this can be used:

ProxyPass / http://127.0.0.1:3000/ upgrade=websocket

https://httpd.apache.org/docs/2.4/mod/mod_proxy.html#protoupgrade

answered Aug 17 '23 at 12:21

Karel Vlk

230
1
6

Apache2 WebSockets reverse proxy on same URL

3 Answers3

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