"policy": "eyJleHBpcmF0aW9uIjoiMjAxNS0QwMToxMTo...", "x-amz-credential": "5TQ/eu-west-1/s3/aws4_request", "x-amz-algorithm": "AWS4-HMAC-SHA256", "x-amz-date": "20151024T001129Z", "x-amz-signature": "c1eb634f83f96b69bd675f535b3..." } } 2. POST https://my-bucket.s3.amazonaws.com Content-Type: multipart/form-data […file content…]