Lock screen on MQTT command

main.py

@@ -5,11 +5,58 @@ logging.basicConfig(
         level=logging.DEBUG if DEBUG else logging.INFO)
 
 import subprocess
+import socket
+import asyncio
+from aiomqtt import Client, TLSParameters
 
+tls_params = TLSParameters(
+    ca_certs='/etc/ssl/certs/ISRG_Root_X1.pem',
+)
+
+HOSTNAME = socket.gethostname()
 
 def lock_screen():
     subprocess.run(['xdg-screensaver', 'lock'])
 
+async def process_lock_command(text):
+    target = text
+
+    logging.info('Lock target: %s', text)
+
+    if target == HOSTNAME or target == 'all':
+        logging.info('Locking screen...')
+        lock_screen()
+
+async def process_mqtt(message):
+    text = message.payload.decode()
+    topic = message.topic.value
+    logging.debug('MQTT topic: %s, message: %s', topic, text)
+
+    if topic.startswith('lock'):
+        await process_lock_command(text)
+    else:
+        logging.debug('Invalid topic, returning')
+        return
+
+async def fetch_mqtt():
+    await asyncio.sleep(3)
+
+    async with Client(
+        hostname='mqtt-dev.dns.t0.vc',
+        port=8081,
+        #username='reader',
+        #password=secrets.MQTT_READER_PASSWORD,
+        tls_params=tls_params,
+    ) as client:
+        await client.subscribe('#')
+        async for message in client.messages:
+            loop = asyncio.get_event_loop()
+            loop.create_task(process_mqtt(message))
 
 if __name__ == '__main__':
-    lock_screen()
+    logging.info('')
+    logging.info('==========================')
+    logging.info('Booting up...')
+
+    loop = asyncio.get_event_loop()
+    loop.run_until_complete(fetch_mqtt())