Merge pull request #277 from quartiq/feature/mqtt-utility-script

Adding general MQTT utility for stabilizer

stabilizer.py

@@ -0,0 +1,144 @@
+#!/usr/bin/python
+"""
+Author: Vertigo Designs, Ryan Summers
+
+Description: Provides an API for controlling Stabilizer over Miniconf (MQTT).
+"""
+import argparse
+import asyncio
+import json
+import logging
+
+from gmqtt  import Client as MqttClient
+
+
+class MiniconfApi:
+    """ An asynchronous API for controlling Miniconf devices using the MQTT control interface. """
+
+    @classmethod
+    async def create(cls, identifier, broker):
+        """ Create a connection to MQTT for communication with the device. """
+        client = MqttClient(client_id='')
+        await client.connect(broker)
+        return cls(client, identifier)
+
+
+    def __init__(self, client, identifier):
+        """ Consructor.
+
+        Args:
+            client: A connected MQTT5 client.
+            identifier: The ID of the device to control.
+        """
+        self.client = client
+        self.identifier = identifier
+        self.client.on_message = self._handle_response
+        self.inflight_settings = dict()
+        self.logger = logging.getLogger('stabilizer.miniconf')
+
+        self.client.subscribe(f'{identifier}/feedback/#')
+
+
+    def _handle_response(self, _client, topic, payload, *_args, **_kwargs):
+        """ 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.
+        """
+        if topic not in self.inflight_settings:
+            self.logger.warning('Unknown response topic: %s', topic)
+            return
+
+        # Indicate a response was received for the provided topic.
+        self.inflight_settings[topic].set_result(payload.decode('ascii'))
+
+
+    async def command(self, path, value):
+        """ Write the provided data to the specified path.
+
+        Args:
+            setting: The path to write the message to.
+            value: The value to write to the path.
+
+        Returns:
+            The received response to the command.
+        """
+        setting_topic = f'{self.identifier}/{path}'
+        response_topic = f'{self.identifier}/feedback/{path}'
+        assert response_topic not in self.inflight_settings, \
+            'Only one in-flight message per topic is supported'
+
+        self.logger.debug('Sending %s to "%s"', value, setting_topic)
+        self.inflight_settings[response_topic] = asyncio.get_running_loop().create_future()
+        self.client.publish(setting_topic, payload=value, qos=0, retain=False,
+                            response_topic=response_topic)
+
+        response = await self.inflight_settings[response_topic]
+        del self.inflight_settings[response_topic]
+
+        return response
+
+
+async def configure_settings(args):
+    """ Configure an RF channel. """
+    logger = logging.getLogger('stabilizer')
+
+    # Establish a communication interface with stabilizer.
+    interface = await MiniconfApi.create(args.stabilizer, args.broker)
+
+    request = None
+
+    # In the exceptional case that this is a terminal value, there is no key available and only a
+    # single value.
+    if len(args.values) == 1 and '=' not in args.values[0]:
+        if args.values[0][0].isalpha():
+            request = args.values[0]
+        else:
+            request = json.loads(args.values[0])
+    else:
+        # Convert all of the values into a key-value list.
+        request = dict()
+        for pair in args.values:
+            key, value = pair.split('=')
+            request[str(key)] = json.loads(value)
+    logger.debug('Parsed request: %s', request)
+
+    response = await interface.command(f'settings/{args.setting}', json.dumps(request))
+    logger.info(response)
+
+    if args.commit:
+        response = await interface.command('commit', 'commit')
+        logger.info(response)
+
+
+def main():
+    """ Main program entry point. """
+    parser = argparse.ArgumentParser(description='Stabilizer settings modification utility')
+    parser.add_argument('--stabilizer', type=str, default='stabilizer',
+                        help='The identifier of the stabilizer to configure')
+    parser.add_argument('--setting', required=True, type=str, help='The setting path to configure')
+    parser.add_argument('--broker', default='10.34.16.1', type=str, help='The MQTT broker address')
+    parser.add_argument('values', nargs='+', type=str,
+                        help='The value of settings. key=value list or a single value is accepted.')
+    parser.add_argument('--commit', action='store_true',
+                        help='Specified true to commit after updating settings.')
+    parser.add_argument('-v', '--verbose', action='store_true', help='Enable verbose logging')
+
+    args = parser.parse_args()
+
+    logger = logging.getLogger('stabilizer')
+    logger.setLevel(logging.INFO)
+
+    if args.verbose:
+        logger.setLevel(logging.DEBUG)
+
+    logging.basicConfig(format='%(asctime)s [%(levelname)s] %(message)s')
+
+    loop = asyncio.get_event_loop()
+    loop.run_until_complete(configure_settings(args))
+
+
+if __name__ == '__main__':
+    main()