HTTP status codes the server can generate in response to an HTTP
200 OK: Successful request.
400 Bad Request: Invalid argument (invalid request payload).
403 Forbidden: Permission denied (invalid API key/quota exceeded).
500 Internal Server Error: Internal server error (retry your request).
503 Service Unavailable: Unavailable.
504 Gateway Timeout: Deadline exceeded (retry your request).
Note: Clients that receive an unsuccessful HTTP response (that is, any HTTP
status code other than
200 OK) must enter
Possible reasons for receiving HTTP status code
400 Bad Request: