async def __aenter__(self) -> Self:
event_bus.register(self.topic + "/get", self.__get_sensors)
event_bus.register(self.topic + "/get_config",
self.__get_sensor_config)
event_bus.publish(self.topic + "/status_update",
True) # FIXME: use a proper event
return self
async def monitor_changes(self, timeout):
"""
Push changes from the database onto the event_bus.
Parameters
----------
timeout: float
The timeout in seconds to wait after a connection error.
"""
async for change_type, change in self._monitor_database(
TinkerforgeSensorModel, timeout):
# Remember: Do not await in the iterator, as this stops the stream of updates
if change_type == ChangeType.UPDATE:
change_dict = change.dict()
# Rename the id key, because we use the parameter uuid throughout the program, because `id` is already
# used in Python
change_dict["uuid"] = change_dict.pop(
"id") # Note uuid will be moved to the end of the dict.
event_bus.publish(
f"nodes/by_uuid/{change_dict['uuid']}/remove", None)
event_bus.publish(
f"nodes/tinkerforge/{change_dict['uid']}/update",
change_dict)
elif change_type == ChangeType.ADD:
change_dict = change.dict()
change_dict["uuid"] = change_dict.pop(
"id") # Note uuid will be moved to the end of the dict.
event_bus.publish(
f"nodes/by_uuid/{change_dict['uuid']}/remove", None)
event_bus.publish(
f"nodes/tinkerforge/{change_dict['uid']}/update",
change_dict)
elif change_type == ChangeType.REMOVE:
# When removing sensors, the DB only returns the uuid
event_bus.publish(f"nodes/by_uuid/{change_dict}/remove", None)
async def run(self) -> None:
"""
The main task, that reads data from the sensors and pushes it onto the event_bus.
"""
# Generate the UUIDs of new sensors
sensor_stream = stream.chain(
stream.iterate(
iterate_safely(f"{self.__topic}/get",
f"{self.__topic}/status_update")),
stream.iterate(event_bus.subscribe(f"{self.__topic}/add_host")),
) | pipe.flatmap(
lambda item: stream.chain(
(stream.call(event_bus.call, f"{self.__topic}/get_config", item
) | catch.pipe(TopicNotRegisteredError)),
stream.iterate(
event_bus.subscribe(f"nodes/by_uuid/{item}/update")),
)
| pipe.until(lambda config: config is None)
| pipe.map(lambda config: config if self._is_config_valid(
self.__node_id, config) else None)
| pipe.map(self._create_transport)
| pipe.switchmap(lambda transport: stream.empty() if transport is
None else stream.iterate(transport.stream_data()))
| pipe.action(lambda data: event_bus.publish("wamp/publish", data)
))
await sensor_stream
def _stream_transport(transport: TinkerforgeTransport):
sensor_stream = stream.chain(
stream.call(transport.enumerate) | pipe.filter(lambda x: False),
stream.iterate(transport.read_enumeration())
| pipe.action(lambda enumeration: event_bus.publish(f"nodes/tinkerforge/{enumeration[1].uid}/remove", None))
| pipe.filter(lambda enumeration: enumeration[0] is not EnumerationType.DISCONNECTED)
| pipe.starmap(lambda enumeration_type, sensor: TinkerforgeSensor(sensor))
| pipe.map(lambda sensor: sensor.stream_data())
| pipe.flatten(),
) | context.pipe(
transport,
on_enter=lambda: logging.getLogger(__name__).info(
"Connected to Tinkerforge host at %s (%s).", transport.uri, transport.label
),
on_exit=lambda: logging.getLogger(__name__).info(
"Disconnected from Tinkerforge host at %s (%s).", transport.uri, transport.label
),
)
return sensor_stream