Incorrect Accept header in DownloadReleaseAsset.

[SteelPhase]

go-github/github/repos_releases.go

Line 256 in d2b80df

acceptHeaders := []string{defaultMediaType, mediaTypeGraphQLNodeIDPreview}

I was able to confirm with curl, that removing mediaTypeGraphQLNodeIDPreview from the Accept header will result in the server returning the correct response.

With the mediaTypeGraphQLNodeIDPreview Accept header the v3 json response is returned.

[dmitshur]

Thanks for reporting. I suspect this is a bug that affects all GitHub versions. mediaTypeGraphQLNodeIDPreview should not have been added to that endpoint, because it operates on binary data, not JSON.

mediaTypeGraphQLNodeIDPreview should be set for GetReleaseAsset method.
It should not be set for DownloadReleaseAsset method.

We should remove mediaTypeGraphQLNodeIDPreview from DownloadReleaseAsset.

[rhysd]

I'm also facing this problem even if I use GitHub API (not enterprise). After the mediaTypeGraphQLNodeIDPreview is added, a binary file downloaded with the method is broken. I confirmed that removing mediaTypeGraphQLNodeIDPreview from the custom accept headers fixed the problem.