"""
w1thermsensor
~~~~~~~~~~~~~
A Python package and CLI tool to work with w1 temperature sensors.
:copyright: (c) 2020 by Timo Furrer <tuxtimo@gmail.com>
:license: MIT, see LICENSE for more details.
"""
# NOTE(TF):
# This examples uses async producers which read
# temperature from sensors and a threaded consumer
# which consumes all the read temperature and does
# something with it.
import asyncio
import threading
import time
from dataclasses import dataclass
from w1thermsensor import AsyncW1ThermSensor
@dataclass
class Reading:
sensor_id: str
timestamp: float
temperature: float
async def produce_readings(sensor: AsyncW1ThermSensor, queue: asyncio.Queue):
"""Single async producer which reads a temperature from a single sensor"""
while True:
timestamp = time.time_ns() / 1e9
temperature = await sensor.get_temperature()
await queue.put(Reading(sensor.id, timestamp, temperature))
def consumer(queue):
while True:
try:
reading = queue.get_nowait()
except asyncio.QueueEmpty: # no reading is available
continue
# do something very fancy with the reading ...
print(reading)
queue.task_done()
def main():
# create queue to share readings between producers and consumer
queue = asyncio.Queue()
# create an async producer for each available sensor
producers = [
produce_readings(sensor, queue)
for sensor in AsyncW1ThermSensor.get_available_sensors()
]
print(f"Created {len(producers)} producers ...")
# create threaded consumer
consumer_thread = threading.Thread(target=consumer, args=(queue,))
consumer_thread.daemon = True
consumer_thread.start()
loop = asyncio.get_event_loop()
try:
for producer in producers:
asyncio.ensure_future(producer)
loop.run_forever()
except KeyboardInterrupt:
pass
finally:
loop.close()
if __name__ == "__main__":
main()
