BGP state monitor sets Event values of incorrect types, causing strange Pydantic serialization errors

[lunkwill42]

When running Zino 2.0.0-beta.1 on real world devices, it intermittently logs a bunch of errors like this:

/home/mvold/.virtualenvs/zino2/lib/python3.11/site-packages/pydantic/main.py:415: UserWarning: Pydantic serializer warnings:
  Expected `Union[PortStateEvent, BGPEvent, BFDEvent, ReachabilityEvent, AlarmEvent, Event]` but got `BGPEvent` - serialized value may not be as expected
  Expected `enum` but got `str` - serialized value may not be as expected
  Expected `enum` but got `str` - serialized value may not be as expected
  Expected `Union[PortStateEvent, BGPEvent, BFDEvent, ReachabilityEvent, AlarmEvent, Event]` but got `BGPEvent` - serialized value may not be as expected
  Expected `enum` but got `str` - serialized value may not be as expected
  Expected `enum` but got `str` - serialized value may not be as expected
...

This appears to be mainly be caused by how this dataclass is used:

zino/src/zino/tasks/bgpstatemonitortask.py

Lines 55 to 61 in c9909f3

	@dataclass
	class BaseBGPRow:
	peer_state: BGPOperState
	peer_admin_status: BGPAdminStatus
	peer_remote_address: IPAddress
	peer_remote_as: int
	peer_fsm_established_time: int

Instances of this class are fed raw string values (as collected through SNMP and parsed through the BGP mibs) as attribute values, not values of the actual annotated types.

Later, these values are fed directly into BGPEvent object attributes: But these objects are Pydantic model instances and do not expect strings as values for attributes such as bgpos and bgpas. As the data is serialized, it complains that these fields aren't the expected enum types BGPOperState and BGPAdminStatus:

zino/src/zino/statemodels.py

Lines 355 to 361 in 938cdc7

	class BGPEvent(Event):
	type: Literal["bgp"] = "bgp"
	remote_addr: Optional[IPAddress] = None
	remote_as: Optional[int] = None
	peer_uptime: Optional[int] = None
	bgpos: Optional[BGPOperState] = None
	bgpas: Optional[BGPAdminStatus] = None