device twin reported property

Question

Hello Everyone,

Is it possible to completely delete the device twin reported property.

I know I can use

{

"property1": null,  

"property2": null  

}

but i have added many new reported property and would like to delete all in one go.

If yes, how can i do it using mqtt topic ?

Thanks

Answer 1

Hello @Bhavin Dhola,

welcome to this moderated Azure community forum.

If I compare your question to what is offered for desired properties maintenance, I expect your need to remove each (high level) reported property yourself.

Look at the portal experience of Azure IoT device twin:

The Azure portal tells us to remove each item, we cannot remove all desired properties at once:

set the value of the item to be removed to 'null'.

Your devices are the owner of their own reported properties, so the code in the devices need to maintain their reported properties.

Only nested properties can be deleted all at once but you still have to set the highest level property to null.

As an alternative, you could request the full twin using the "$iothub/twin/GET/?$rid=42" topic.

note: this contains the desired properties also. An example written in C# is seen here.

Then, you could iterate through the reported properties and remove them dynamically.

This is probably a lot of code and only viable when you do not know the exact names of each reported property.

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Answer 2

Hi, Welcome to MS Q&A

I think yes please find below detailed steps

1. Connect to Azure IoT Hub: Use an MQTT client library to connect to Azure IoT Hub. You'll need to provide the appropriate connection parameters like the hostname, device ID, and SAS token.
2. Publish the PATCH Request: Publish a message to the appropriate MQTT topic for updating reported properties. The topic should look like $iothub/twin/PATCH/properties/reported/?$rid={request_id}. Replace {request_id} with a unique identifier for the request.
3. Payload: In the payload of the message, send an empty JSON object {}. This indicates that you want to delete all reported properties.
4. Receive Response: Subscribe to the response topic to receive acknowledgment or response messages from Azure IoT Hub.

Please check these docs and imag for ref

https://learn.microsoft.com/en-us/azure/iot/iot-mqtt-connect-to-iot-hub

kindly accept answer if it helps, Thanks!, if you have any further questions , please let me know