Important HTTP Status Code

Success

• 200: Success
  • Can be used for any requests
• 201: Created ^5842b1
  • Can be used for POST or PUT typically when using to upload a file.
• 204: No content
  • No content sent back but header might be useful

Redirection

• 301: Permanent redirect
  • Browser will cache the response
  • Save cost for server load
  • Consider using
    • 308 if we want to keep the same method type (GET -> GET, POST -> POST)
• 302: Temporary redirect
  • Browser will not cache the response
  • Good for analytics
  • Consider using
    • 307 if we want to keep the same method type (GET -> GET, POST -> POST)

Client error

• 400: Bad request
  • Due to problem from client error: (malformed syntax, invalid request)
• 401: Unauthorised
  • Require authentication to access
• 403: Forbidden
  • Authenticated but doesn't have permission
• 404: Not found
• 405: METHOD not allowed
  • The URL is available but METHOD is not available.
  • For example we cannot DELETE a resource. Therefore we return 405
• 415: Unsupported media type
• 429: Too many requests

Server error

• 500: Internal server error
• 502: Bad gateway.
  • The server while calling other API has invalid response, hence return 502 to the current user saying that it's another party issue
• 504: Gateway timeout
  • The server is timeout from the upstream server and return back to client