How to point a WebSocket to the current server

Question

I have a Jetty 8 server running (hopefully soon with websockets).

If I want to send some data to the server with an ajax call, I can do this:

$.ajax({ url: "ajax?a=getSomeData" }); 

In this scenario, if I connect to my server at 192.168.1.100, the real url where it will get the data from, will be 192.168.1.100/ajax?a=getSomeData, but if I connect to another server running the same software at 192.168.1.200, the url will be 192.168.1.200/ajax?a=getSomeData.

But if I want to accomplish the same thing using WebSockets, I cannot find how to do it:

var socket = new WebSocket('ws://www.example.com/'); 

Works. But I want something like a relative url:

var socket = new WebSocket('ws://sockets?a=getSomeData'); 

So that - like the ajax request - if I were connecting to my server at 192.168.1.100, the url will be 192.168.1.100/sockets?a=getSomeData, and if I connect to 192.168.1.200, the url will be 192.168.1.200/sockets?a=getSomeData.

How can I accomplish this?

Answer 1

Just build the URL yourself:

var socket = new WebSocket("ws://" + location.host + "/whatever"); 

The location object is a property of the window object, and is therefore globally available.

To get only the host without the port, use location.hostname instead. If the websocket server listens on another port for example.

You can also inspect location.protocol to know if you should connect to wss (when https is used) or ws (when http is used).