Best practice: How granular should by Notifiers be?

[janpeterka]

As I'm implementing notifications, I am not really sure how many Notifiers I should have.
I know there's not a right or wrong way, I'm just interested in how different people approach this.

For context: My app is basically IS for choirs and music bands; having events, announcements, comments,..., nothing complicated.

So what are my options?

Have just ApplicationNotifier

I my usecase, everything would pretty much work with only one notifier, as I specify record and message in each case.
Is there some downside to that?

Have ObjectNotifiers

Another option is to split notifiers by objects - EventNotifier, CommentNotifier,..
It might make orientation easier, and probably also specify how the notification is shown in UI (like notification_message or something).

Have specific Notifier for every event

I can go "all in" and have EventCreationNotifier, CommentUpdateNotifier,...
This would allow me to specify message in Notifier. It makes sense to me, but at the same time, it seems bit unnecessary.

So, I just want some discussion - how did you think about this stuff when you implement your notification system.

[excid3]

Separate notifiers are most useful when you've got different content for each. For example, you may want to send a different email for a new event vs a new comment.

If they're all about the same, then a single notifier might do the trick.