[BUG]: HttpError: Failed to fetch (CORS policy)

[mchestnut]

What happened?

We are seeing sporadic POST requests using octokit/rest.js failing. The requests come back with the error HttpError: Failed to fetch and Access to fetch at 'https://api.github.com/repos/ChapmanAutoGroup/sites.retail/git/trees' from origin [our site] has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.

We're calling the git.createTree and git.createBlob methods. We have seen it fail on either one at different times.

We've also noticed that attempting the same exact request using the same headers and payload will eventually result in a success, although the number of retries can vary from 1 to over a dozen.

The library is being using in a Vue app. We've seen the error running both locally and on a production server.

Any ideas what is causing the CORS issue?

Versions

node: 18.17.1 @octokit/rest: 20.0.2

Relevant log output

No response

Code of Conduct

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[github-actions[bot]]

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[wolfy1339]

This seems more like a GitHub infrastructure issue than an issue with Octokit itself

[cscheffauer]

experiencing the same - can someone have a look at this?

[wolfy1339]

Please raise this issue with GitHub.

CORS issues are server-side, not client-side.

There is nothing we can do. It's GitHub that has not set the required header.