fix(event-bus): event id is optional

[Sikora00]

Handle case when a class without
any handler was published.

Closes #924

PR Checklist

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PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Other... Please describe:

What is the current behavior?

Issue Number: 924

What is the new behavior?

Does this PR introduce a breaking change?

• Yes
• No

Other information

[kamilmysliwiec]

LGTM

[ruslanguns]

This PR makes it mandatory to setup an event handler per event impl, I thought event impl. shouldn't know about handers. I got an issue since I was triggering an event (which I wasn't expecting to do anything just calling a class in this.apply( new MyEvent() ).

If this is an expected behavior I think it would be much better to have a better logging error to know which specific Event was not implemented (with an undefined ID)

But in my humble opinion, obviously since I am not master of CQRS, I think an implementation should be decoupled from handlers.

[kamilmysliwiec]

@Sikora00 can you look into this? We should probably just ignore events that don't have associated event handlers instead of throwing such errors

[Sikora00]

@ruslanguns what version of @nestjs/cqrs do you use? I don't see the change introduced with this PR on your screenshots.
I exactly made it optional here :D

[ruslanguns]

You are right (I was in the wrong version) I feel so embarrassed. Please excuse me!