Calling other services.
WHAT THE FRAMEWORK PROVIDES
An HTTP client with a clear interface.
WHAT TO ALWAYS SET
A timeout.
Without one, a hanging request holds your process.
WHAT TO HANDLE
Network failure Unexpected status codes Responses not in the expected format Rate limits
WHAT TO IMPLEMENT
Retries with increasing delay, for temporary failures only.
WHAT NOT TO RETRY
Failures that will not resolve, such as invalid credentials.
WHERE TO PUT THE CODE
A dedicated class per service, not scattered through controllers.
WHY
So it can be substituted in tests and changed in one place.
WHAT TO KEEP IN CONFIGURATION
Endpoints and credentials.
WHAT TO QUEUE
Calls made during a request, where the result is not needed immediately.
WHAT TO CACHE
Responses that change rarely.
WHAT TO VALIDATE
The response structure, before relying on it.
WHAT TO LOG
Failures, with enough context to diagnose, and never the credentials.
