MQTT publish payload as binary data

🚧 Developers Coding Questions
1

I have a requirement to publish MQTT payload as binary.

The incoming parse(String message) message payload is base64 and then I am able to decode fine back to binary, but the

> interfaces.mqtt.publish(String topic, String payload)

does not seem to allow any method to notify the mqtt client to change the payload to binary before it sends.

Any help on this?

2

Maybe change the payload to a byte array and then send it ...

3

Yea, tried that and everything else like casting (String) or 'as String' on the byte array that I need to send. The publish method forced the type as String which I would think would need to know it was base64 or some other protocol to move binary via String type.

SOOOOO close to having a working native solution for Roborock and this is the last step. I managed though all the user log in stuff, tokens, subscriptions, AES encryption to get stuck here. :frowning:

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4

I would think UTF-8

5

Tried it and all of these:

   byte[] message = my binary message that is encypted.  
   String payload = new String(message, "UTF-8")
   String payload = message.encodeAsBase64()
   String payload = message as String
   String payload = (String)message
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6

Doesn't seem to be any tricks available in the methods provided unless "publishMqttMessage" has something hidden.

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@bravenel @bobbyD any thoughts or help moving binary via mqtt publish?

7

Found the answer. Probably good to read the documents. You need to set the connect() to byteInterface to true and then pass the as message.encodeHex().toString()

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