I want to add CORS support to my server

For simple CORS requests, the server only needs to add the following header to its response:

Access-Control-Allow-Origin: *

There are some more headers and settings involved if you want to support verbs other than GET/POST, custom headers, or authentication. You can learn more about these options in the Using CORS tutorial on HTML5 Rocks.

If you want the TL;DR version, take a look at the flowchart for implementing CORS support.

If you'd like to learn more about implementing CORS for a specific platform, follow one of the links below:

Who’s behind this

Monsur Hossain and Michael Hausenblas

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