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APIs Posting Data with fetch()

Joseph Michelini
.a{fill-rule:evenodd;}techdegree seal-36
Joseph Michelini
Python Development Techdegree Graduate 18,692 Points

When I post, it doesn't post to console. But after a bit I am receiving this super weird error. Help!

What's going on here? I feel like it's beyond the scope of this course but I could be wrong. This error only shows up after maybe 30 seconds? And in the meantime the comment has not been logged to the console. I've resorted to using the "final" code just to make sure I didn't make any errors of my own and it still happens.

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Also, if for some reason you can't zoom in on that here, here's the Imgur link: https://imgur.com/IoIJ2Em


1 Answer

Steven Parker
Steven Parker
208,505 Points

CORS is a security feature in browsers that prevents a page loaded from one site from accessing information from a different site unless it has explicit permissions added by the systems in the HTTP message headers.

I think the workspace server might add these permissions automatically; but if you're working on a system that doesn't do this by default, you'll need to provide server configuration (or code) to allow CORS access.