I’m trying to authenticate against azures batch REST interface from my php server. According to the docs (https://docs.microsoft.com/en-us/rest/api/batchservice/authenticate-requests-to-the-azure-batch-service) I came up with this function: However, I always get a 403 error: “Server failed to authenticate the request. Make sure the value of Authorization header is formed correctly including the signature” Due to the complicated setup and the vague error message,