Unmatched Signatures (SDK for Node.js)

Problem: The HTTP status code obtained from CommonMsg.Status was 403, and the OBS server-side error code obtained from CommonMsg.Code was SignatureDoesNotMatch.

Solution:

1. Check whether a bucket name was added before the endpoint. This will lead to a signature mismatch.
2. Ensure that the AK and SK matched, were both correctly specified, and were the same as those used in the request.
3. Check StringToSign.
   The structure of StringToSign should be as follows:

   HTTP-Verb + "\n" + Content-MD5 + "\n" + Content-Type + "\n" + Date + "\n" + CanonicalizedHeaders + CanonicalizedResource