使用HTTP POST上传AWS S3浏览器会产生无效签名

I'm working on a website where the users should be able to upload video files to AWS. In order to avoid unnecessary traffic I would like the user to upload directly to AWS (and not through the API server). In order to not expose my secret key in the JavaScript I'm trying to generate a signature in the API. It does, however, tell me when I try to upload, that the signature does not match.I'm working on a website where the users should