A tiny, modern MQTT/UDP client.

• Brokerless broadcasting of MQTT messages
• Fire-and-forget
• Reliable transmission support with QoS level 1
• Polling using SUBSCRIBE messages
• Ping messages for client discovery
• No dependencies and single-file distributable for easy vendoring and embedded systems

MQTT/UDP is based on MQTT v3.1.1 but it does not aim to be 100% compatible. The following are not implemented nor planned:

• CONNECT, CONNACK, SUBACK, UNSUBSCRIBE, UNSUBACK, DISCONNECT, and AUTH messages
• PUBREC, PUBREL, and PUBCOMP (QoS level 2)
• Packet Identifier in SUBSCRIBE messages
• Multiple topics in SUBSCRIBE messages
• Retained messages
• Authentication
• Message Properties

The following are not done automatically but can be easily implemented by the user:

• Replying to PUBLISH with PUBACK (QoS level 1)
• Replying to PINGREQ with PINGRESP
• Resending unacknowledged messages

These are the most bare-bones examples to get you started.

Sending messages:

from mqtt_udp import Client

with Client() as client:
    client.publish("demo/topic", b"hello")

Receiving messages:

from mqtt_udp import Client

with Client() as client:
    for packet in client.listen():
        print(packet)

For more complete examples that you can use right away, check out the examples directory.

MIT License

This implementation is based on this desciption of MQTT/UDP by Dmitry Zavalishin. Many thanks to him for the idea and prior work!