Knowledge Base

Does Node.js on Plesk support WebSockets (socket.io)?

Question

Does Node.js and Ruby on Plesk support WebSockets (socket.io)?

How to provide WebSockets feature to customers?

Answer

Plesk itself does not forbid to use WebSockets, it only provides runtime environment to run Node.js and Ruby using Phusion Passenger, or iisnode.
The rest depends on particular website code design/implementation details.

On Linux

Note: Websockets work properly only if nginx-only web hosting is configured (with Proxy mode disabled) due to the following Apache module issue: WebSockets don't work on Apache.

Log into Plesk
Go to Websites & Domains > example.com > Apache & nginx Settings
In the nginx settings section, clear the Proxy mode checkbox

Note: In case this checkbox is not present, install, or enable nginx.
Click on Apply

On Windows

Log into Plesk
Navigate to Domains > example.com > File Manager
Open the web.config file in the application's document root, and add the following configuration to the <system.webServer> section:

<rewrite>
<rules>
<rule name="SocketIO" patternSyntax="ECMAScript">
<match url="socket.io.+" />
<action type="Rewrite" url="app.js" />
</rule>
</rules>
</rewrite>

Note: In case <rewrite> section already exists in the configuration file, instead add the <rule> part to the existing <rules>

The sample "Phusion Passenger: Node.js WebSocket demo" application can be used to verify whether WebSocket connections are working fine on the webserver: https://github.com/phusion/passenger-nodejs-websocket-demo