Hi folks...
A ran into a problem recently with uploading custom game servers through the playfab web API, and it took me several hours to figure out what's wrong. I'm not the first with this one, I've found 4-5 posts here about the issue. The problem was that I kept getting SignatureDoesNotMatch from S3 for the presigned URL that GetServerBuildUploadUrl returned. It turned out that the problem was the content type, and only application/x-zip-compressed is accepted (neither g-zip or octet-stream etc.). So I would suggest putting this in the docs ASAP, because it's never mentioned...
Cheers
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