57 lines
2.2 KiB
Python
57 lines
2.2 KiB
Python
# Example of using the MQTT client class to subscribe to a feed and print out
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# any changes made to the feed. Edit the variables below to configure the key,
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# username, and feed to subscribe to for changes.
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# Import standard python modules.
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import sys
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# Import Adafruit IO MQTT client.
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from Adafruit_IO import MQTTClient
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# Set to your Adafruit IO key & username below.
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ADAFRUIT_IO_KEY = 'YOUR ADAFRUIT IO KEY'
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ADAFRUIT_IO_USERNAME = 'YOUR ADAFRUIT IO USERNAME' # See https://accounts.adafruit.com
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# to find your username.
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# Set to the ID of the feed to subscribe to for updates.
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FEED_ID = 'DemoFeed'
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# Define callback functions which will be called when certain events happen.
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def connected(client):
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# Connected function will be called when the client is connected to Adafruit IO.
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# This is a good place to subscribe to feed changes. The client parameter
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# passed to this function is the Adafruit IO MQTT client so you can make
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# calls against it easily.
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print('Connected to Adafruit IO! Listening for {0} changes...'.format(FEED_ID))
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# Subscribe to changes on a feed named DemoFeed.
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client.subscribe(FEED_ID)
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def disconnected(client):
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# Disconnected function will be called when the client disconnects.
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print('Disconnected from Adafruit IO!')
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sys.exit(1)
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def message(client, feed_id, payload, retain):
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# Message function will be called when a subscribed feed has a new value.
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# The feed_id parameter identifies the feed, and the payload parameter has
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# the new value.
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print('Feed {0} received new value: {1}'.format(feed_id, payload))
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# Create an MQTT client instance.
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client = MQTTClient(ADAFRUIT_IO_USERNAME, ADAFRUIT_IO_KEY)
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# Setup the callback functions defined above.
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client.on_connect = connected
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client.on_disconnect = disconnected
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client.on_message = message
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# Connect to the Adafruit IO server.
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client.connect()
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# Start a message loop that blocks forever waiting for MQTT messages to be
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# received. Note there are other options for running the event loop like doing
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# so in a background thread--see the mqtt_client.py example to learn more.
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client.loop_blocking()
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