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A comment on You don't need that CORS request. Parent comment

Re:You don't need that CORS request by CSDude on Monday January 03, 2022 @04:20AM (#29778857)
Not sure why you cannot strip in your backend, and it's a huge deal. Code needs to be run somewhere though. While Lambda@Edge sucks, Cloudfront runs functions now which is not Lambda@Edge, and faster because it executes on the PoP location. https://aws.amazon.com/blogs/aws/introducing-cloudfront-func...
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Re:You don't need that CORS request by herpderperator on Monday January 03, 2022 @12:55PM (#29783804)
CloudFront Distributions cannot pass the request to CloudFront Functions before sending to the origin. In other words, they cannot be used to modify origin request/responses. They can only modify the viewer request/responses. [0]

Only Lambda@Edge can help the scenario which I provided, which is also AWS's recommended solution. [1]

[0] https://docs.aws.amazon.com/AmazonCloudFront/latest/Develope...

[1] https://aws.amazon.com/blogs/architecture/serving-content-us...

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Re:You don't need that CORS request by CSDude on Monday January 03, 2022 @02:30PM (#29785238)
I've just tried it. The following function works exactly as-is when the function is configured as Viewer request. I changed it to append some text to URL.

See: https://github.com/aws-samples/amazon-cloudfront-functions/b...

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Re:You don't need that CORS request by herpderperator on Tuesday January 04, 2022 @09:02PM (#29804003)
That MODIFIES a viewer request, resulting in a viewer redirect. We want to keep the viewer request the same, i.e. with /api, and strip it only from the backend origin request.

The viewer request is the one you make from the client, with /api. The origin request is the one CloudFront sends to your backend, which, without using Lambda@Edge via the origin request, will get sent as-is with the /api prefix. You have to strip it from the origin request.

If you strip /api from the viewer request, your `domain.com/api/users` request becomes a redirect to `domain.com/users` which results in a call to your frontend instead of your backend.

The example you referenced solves a completely different issue, not the one we are talking about.

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