Azure IoT Central - Display Command execution results

Question

how to display Commands results in IoT Central - Commands page?

Flow:

• Command sent to Device
• Device received the command and returns Payload:

{
  "status": 200,
  "payload": {
    "command": "ping",
    "result_code": "ok",
    "result_data": "ping 5 ms"
  }
}

How to display this data in IoT Central?

Now IoT Central shows only default "Sent at ..." message.

Answer 1

If you set a reported property with the same name as the command when you handle the command on the device, then you can set a value that displays in the IoT Central UI. For example, using Node.js you can create a handler for a countdown method like this:

function onCountdown(request, response) {
  console.log('received a request for Countdown');
  console.log(JSON.stringify(request.payload, null, 2));
  var fakeResponsePayload = {
    key: 'value'
  };

  response.send(200, fakeResponsePayload, function (err) {
    if (err) {
      console.error('Unable to send method response: ' + err.toString());
    } else {
      console.log('response to Countdown sent.');
      client.getTwin(function(err, twin) {
        if (err) {
          console.error('could not get twin');
        } else {
          console.log('twin created');
          var patch = {
            countdown:{
              value: 18
            }
          };
          twin.properties.reported.update(patch, function(err) {
            if (err) {
              console.error('unable to update twin: ' + err.toString());
            } else {
              console.log('twin state reported');
            }
          });
        }
      });      
    }
  });
}

client.onDeviceMethod('countdown', onCountdown);

Note that the name of the field name of the command is countdown.

There is also a C++ example here: https://github.com/Azure/iot-central-firmware/blob/master/MXCHIP/mxchip_advanced/src/registeredMethodHandlers.cpp