Asynchronous MQTT client for 3.1.1 protocol version.
Recommended way (via pip):
$ pip install aio-mqttSimple echo server:
import asyncio as aio
import logging
import typing as ty
import aio_mqtt
logger = logging.getLogger(__name__)
class EchoServer:
def __init__(
self,
reconnection_interval: int = 10,
loop: ty.Optional[aio.AbstractEventLoop] = None
) -> None:
self._reconnection_interval = reconnection_interval
self._loop = loop or aio.get_event_loop()
self._client = aio_mqtt.Client(loop=self._loop)
self._tasks = [
self._loop.create_task(self._connect_forever()),
self._loop.create_task(self._handle_messages())
]
async def close(self) -> None:
for task in self._tasks:
if task.done():
continue
task.cancel()
try:
await task
except aio.CancelledError:
pass
if self._client.is_connected():
await self._client.disconnect()
async def _handle_messages(self) -> None:
async for message in self._client.delivered_messages('in'):
while True:
try:
await self._client.publish(
aio_mqtt.PublishableMessage(
topic_name='out',
payload=message.payload,
qos=aio_mqtt.QOSLevel.QOS_1
)
)
except aio_mqtt.ConnectionClosedError as e:
logger.error("Connection closed", exc_info=e)
await self._client.wait_for_connect()
continue
except Exception as e:
logger.error("Unhandled exception during echo message publishing", exc_info=e)
break
async def _connect_forever(self) -> None:
while True:
try:
connect_result = await self._client.connect('localhost')
logger.info("Connected")
await self._client.subscribe(('in', aio_mqtt.QOSLevel.QOS_1))
logger.info("Wait for network interruptions...")
await connect_result.disconnect_reason
except aio.CancelledError:
raise
except aio_mqtt.AccessRefusedError as e:
logger.error("Access refused", exc_info=e)
except aio_mqtt.ConnectionLostError as e:
logger.error("Connection lost. Will retry in %d seconds", self._reconnection_interval, exc_info=e)
await aio.sleep(self._reconnection_interval, loop=self._loop)
except aio_mqtt.ConnectionCloseForcedError as e:
logger.error("Connection close forced", exc_info=e)
return
except Exception as e:
logger.error("Unhandled exception during connecting", exc_info=e)
return
else:
logger.info("Disconnected")
return
if __name__ == '__main__':
logging.basicConfig(
level='DEBUG'
)
loop = aio.new_event_loop()
server = EchoServer(reconnection_interval=10, loop=loop)
try:
loop.run_forever()
except KeyboardInterrupt:
pass
finally:
loop.run_until_complete(server.close())
loop.run_until_complete(loop.shutdown_asyncgens())
loop.close()Copyright 2019-2020 Not Just A Toy Corp.
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.