pounder_test/miniconf.py

144 lines
4.9 KiB
Python

#!/usr/bin/python
"""
Author: Vertigo Designs, Ryan Summers
Robert Jördens
Description: Provides an API for controlling Miniconf devices over MQTT.
"""
import argparse
import asyncio
import json
import logging
import sys
import uuid
from gmqtt import Client as MqttClient
LOGGER = logging.getLogger(__name__)
class Miniconf:
"""An asynchronous API for controlling Miniconf devices using MQTT."""
@classmethod
async def create(cls, prefix, broker):
"""Create a connection to the broker and a Miniconf device using it."""
client = MqttClient(client_id='')
await client.connect(broker)
return cls(client, prefix)
def __init__(self, client, prefix):
"""Constructor.
Args:
client: A connected MQTT5 client.
prefix: The MQTT toptic prefix of the device to control.
"""
self.request_id = 0
self.client = client
self.prefix = prefix
self.inflight = {}
self.client.on_message = self._handle_response
self.response_topic = f'{prefix}/response/{uuid.uuid1().hex}'
self.client.subscribe(self.response_topic)
def _handle_response(self, _client, topic, payload, _qos, properties):
"""Callback function for when messages are received over MQTT.
Args:
_client: The MQTT client.
topic: The topic that the message was received on.
payload: The payload of the message.
_qos: The quality-of-service level of the received packet
properties: A dictionary of properties associated with the message.
"""
if topic == self.response_topic:
# Extract request_id corrleation data from the properties
request_id = int.from_bytes(
properties['correlation_data'][0], 'big')
self.inflight[request_id].set_result(json.loads(payload))
del self.inflight[request_id]
else:
LOGGER.warn('Unexpected message on "%s"', topic)
async def command(self, path, value, retain=True):
"""Write the provided data to the specified path.
Args:
path: The path to write the message to.
value: The value to write to the path.
retain: Retain the MQTT message changing the setting
by the broker.
Returns:
The response to the command as a dictionary.
"""
topic = f'{self.prefix}/settings/{path}'
fut = asyncio.get_running_loop().create_future()
# Assign unique correlation data for response dispatch
assert self.request_id not in self.inflight
self.inflight[self.request_id] = fut
correlation_data = self.request_id.to_bytes(4, 'big')
self.request_id += 1
payload = json.dumps(value)
LOGGER.info('Sending "%s" to "%s"', value, topic)
self.client.publish(
topic, payload=payload, qos=0, retain=retain,
response_topic=self.response_topic,
correlation_data=correlation_data)
return await fut
def main():
""" Main program entry point. """
parser = argparse.ArgumentParser(
description='Miniconf command line interface.',
formatter_class=argparse.RawDescriptionHelpFormatter,
epilog='''Examples:
%(prog)s dt/sinara/dual-iir/00-11-22-33-aa-bb iir_ch/0/0=\
'{"y_min":-32767,"y_max":32767,"y_offset":0,"ba":[1.0,0,0,0,0]}'
%(prog)s dt/sinara/lockin/00-11-22-33-aa-bb afe/0='"G2"'\
''')
parser.add_argument('-v', '--verbose', action='count', default=0,
help='Increase logging verbosity')
parser.add_argument('--broker', '-b', default='mqtt', type=str,
help='The MQTT broker address')
parser.add_argument('--no-retain', '-n', default=False,
action='store_true',
help='Do not retain the affected settings')
parser.add_argument('prefix', type=str,
help='The MQTT topic prefix of the target')
parser.add_argument('settings', metavar="PATH=VALUE", nargs='+',
help='JSON encoded values for settings path keys.')
args = parser.parse_args()
logging.basicConfig(
format='%(asctime)s [%(levelname)s] %(name)s: %(message)s',
level=logging.WARN - 10*args.verbose)
loop = asyncio.get_event_loop()
async def configure_settings():
interface = await Miniconf.create(args.prefix, args.broker)
for setting in args.settings:
path, value = setting.split("=", 1)
response = await interface.command(path, json.loads(value),
not args.no_retain)
print(f'{path}: {response}')
if response['code'] != 0:
return response['code']
return 0
sys.exit(loop.run_until_complete(configure_settings()))
if __name__ == '__main__':
main()