What is CORS? Blocked by CORS policy error explained

cores is an acronym for cross-origin resource sharing and it helps keep the web safe by Guardian server resources from requests by unknown Origins like other web apps unless of course they have permission I can simulate this by issuing a fetch request in the dev console from the google.com domain and I'm fetching the mdn.com domain that's Crossing Origins and there we have a course policy error this error message can really confuse beginners though as it suggests possibly setting the request mode to no cores but this setting doesn't turn off cores for the server it just Alters the fetch request for example a request in no cores mode doesn't support Json data as a content type the server admin has to give you permission by setting their Access Control allow origin header to either let everyone access the resources or more commonly let an allowed list of domains have access it's kind of like having a VIP pass for resources and otherwise the course Dorman won't let you pass there's much more to learn about cores and I suggest starting on the mdn cores page

Channel: Dave Gray

Views: 68,334

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Id: 1iOeoRCUD4M

Length: 1min 0sec (60 seconds)

Published: Sun Apr 16 2023