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    Allow CORS in Node.js and Express

    Joel LordJoel Lord

    In this quick lesson, we see how to add the CORS middleware so that our Express server can handle requests from different origins.



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    Instructor: If you have an API that runs on a different server or even a different port than your application, and you try to do a fetch, you should see a message in your console complaining about Access-Control-Allow-Origin.

    The fix for this in your Express server is very simple. First of all, you need to require the CORS library. You'll also need to install it using npm install cors. Secondly, you need to tell your Express server to use this middleware by using app.use and the library that we've just installed.

    Now, if you restart your server and try the same fetch call in your browser, you won't have that CORS error any more.