1916 Add support for custom events in workflows

[Nic-Ma]

Fixes #1916 .

Description

This PR added support to register custom events in the workflows.

Status

Ready

Types of changes

• Non-breaking change (fix or new feature that would not break existing functionality).
• Breaking change (fix or new feature that would cause existing functionality to change).
• New tests added to cover the changes.
• Integration tests passed locally by running ./runtests.sh -f -u --net --coverage.
• Quick tests passed locally by running ./runtests.sh --quick --unittests.
• In-line docstrings updated.
• Documentation updated, tested make html command in the docs/ folder.

[Nic-Ma]

/black

[wyli]

thanks!

[Nic-Ma]

Hi @wyli ,

I also tested in our workflows with:

class TestHandler:
    def attach(self, engine):
        engine.add_event_handler("foo_event", self.test1)
        engine.add_event_handler("gar_event", self.test2)
        engine.add_event_handler(Events.EPOCH_COMPLETED, self)
    
    def __call__(self, engine):
        engine.fire_event("foo_event")
        engine.fire_event("gar_event")

    def test1(self, engine):
        print(engine.state.foo)
    
    def test2(self, engine):
        print(engine.state.gar)

Thanks.