Expose NewBlockEvent on the event bus

[cburgdorf]

What was wrong?

This is a little spin off from #721 that splits peer pool and sync into two separate processes. This exposes a NewBlockEvent on the event bus which is an important event for components to utilize (e.g. to build sync strategies on)

How was it fixed?

• Created NewBlockEvent
• Dispatch the NewBlockEvent whenever the native NewBlock command pops up

To-Do

• Clean up commit history

• Add entry to the release notes

Cute Animal Picture

[cburgdorf]

This seems to be an issue with recent pip versions pypa/pip#6213

[pipermerriam]

I must be missing something. Why does NewBlockEvent not have the block and total_difficulty fields mirrored (same question for NewBlockHashesEvent.)

[cburgdorf]

Because all of these derive from PeerPoolMessageEvent and leave it up to the consumer to unpack things.

trinity/trinity/protocol/common/events.py

Lines 89 to 98 in 06e2c17

	@dataclass
	class PeerPoolMessageEvent(BaseEvent):
	"""
	Base event for all peer messages that are relayed on the event bus. The events are mapped
	to individual subclasses for every different ``cmd`` to allow efficient consumption through
	the event bus.
	"""
	remote: Node
	cmd: Command
	msg: PayloadType

In the long run, I guess we'll get rid of this mapping anyway and have the peer pool be built natively on Lahja. In the meantime, this is just to keep things simple and don't map properties on lots of places.