Use events list for logger handlers

[sdesrozis]

Fixes #1543

Description:

Allow EventsList in BaseLogger attachment. The key point is to attach each event independently as it is done in Engine.

Check list:

• New tests are added (if a new feature is added)
• New doc strings: description and/or example code are in RST format
• Documentation is updated (if required)

[ydcjeff]

LGTM, Thank you!

[vfdev-5]

I think it would be better to use return engine.add_event_handler(event_name, log_handler, self, event_name) for any type of events. Below for loop if considered without check if name not in State.event_to_attr is exactly what is done by Engine.add_event_handler.
I think we can simply generalize event checking like

event_to_check = event_name if isinstance(event_name, EventsList) else [event_name, ]
for name in event_to_check:
    if name not in State.event_to_attr:
        raise RuntimeError(f"Unknown event name '{name}'")

return engine.add_event_handler(event_name, log_handler, self, event_name)

[sdesrozis]

That does not work.

The last argument of the method add_event_handler is a list of events. Internally in engine, there is a loop where the handler is attached at every event in the list. But the list is forwarded to each handler while just each event should be.

If there was no argument to the method, it would work.

Thoughts ?

[vfdev-5]

Yes, you are right. In this case, my suggestion is not valid. OK, let's do it as you proposed.

[vfdev-5]

Thanks for the PR @sdesrozis !

I let you merge it.