The definition of the 502 Bad Gateway
status code is:
The server, while acting as a gateway or proxy, received an invalid response from the upstream server it accessed in attempting to fulfill the request.
Is it an appropriate status code to respond with if the error was caused by the database? Despite the fact that the definition of the 500 Internal Server Error
status code doesn't state that the error has to be internal, I don't like using it when the error is external.
Can the web server be considered to be a gateway or a proxy, since it is performing tasks other than communicating with the database, such as making calls to other APIs and services?