How to set up CORS on your server and jQuery

corsGuide.md

CORS with Ajax Requests

Serverside

Server response has to have these headers:

Access-Control-Allow-Origin:      https://origin.com
Access-Control-Allow-Methods:     POST, GET, OPTIONS, PUT, DELETE
Access-Control-Allow-Headers:     Content-Type, X-Auth-Token, Origin
Access-Control-Allow-Credentials: true

where https://origin.com is the querying host. In case of sending login credentials: Origin must not be *; the browser would reject the server's answer.

Additionally catch OPTIONS-requests and respond with 200 OK and the headers if the requesting host is on the whitelist. 4XX else. Make sure that 4XX-responses send those headers, too.

Clientside

$.ajax({
  ...,
  crossDomain: true,
  xhrFields: {
    withCredentials: true
  }
})

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