Handle edge cases in caching

**Feature request**
It would be great to have notifications for api.

**Use case**
Many users need this functionality for production deployments.

**Implementation idea**
Add a new config option `enable_notifications` with default `false`.

Start by locating the API configuration entry point and the code that handles production deployments; no file or test is named in the issue. Confirm how notifications should be delivered and what events they cover, then add the disabled-by-default enable_notifications option and tests showing the configured behavior.

Written by the indexing model from the issue text.