Use the IoT extension for Azure CLI for Azure IoT Hub device management

In this article, you learn how to use the IoT extension for Azure CLI with various management options on your development machine. The IoT extension for Azure CLI is an open-source IoT extension that adds to the capabilities of the Azure CLI. The Azure CLI includes commands for interacting with Azure Resource Manager and management endpoints. For example, you can use Azure CLI to create an Azure VM or an IoT hub. A CLI extension enables an Azure service to augment the Azure CLI giving you access to additional service-specific capabilities. The IoT extension gives IoT developers command-line access to all IoT Hub, IoT Edge, and IoT Hub Device Provisioning Service capabilities.

For more detailed explanation on the differences and guidance on using these options, see Device-to-cloud communication guidance and Cloud-to-device communication guidance.

Device twins are JSON documents that store device state information (metadata, configurations, and conditions). IoT Hub persists a device twin for each device that connects to it. For more information about device twins, see Get started with device twins.

• Complete the Raspberry Pi online simulator tutorial or one of the device tutorials. For example, you can go to Raspberry Pi with Node.js or to one of the Send telemetry quickstarts. These articles cover the following requirements:

  • An active Azure subscription.
  • An Azure IoT hub under your subscription.
  • A client application that sends messages to your Azure IoT hub.

• Make sure your device is running with the client application during this tutorial.

• Python 2.7x or Python 3.x

• The Azure CLI. If you need to install it, see Install the Azure CLI. At a minimum, your Azure CLI version must be 2.0.70 or above. Use az -version to validate.

  Note

  This article uses the newest version of the Azure IoT extension, called azure-iot. The legacy version is called azure-cli-iot-ext.You should only have one version installed at a time. You can use the command az extension list to validate the currently installed extensions.

  Use az extension remove --name azure-cli-iot-ext to remove the legacy version of the extension.

  Use az extension add --name azure-iot to add the new version of the extension.

  To see what extensions you have installed, use az extension list.

• Install the IoT extension. The simplest way is to run az extension add --name azure-iot. The IoT extension readme describes several ways to install the extension.

Sign in to your Azure account by running the following command:

az login

az iot hub invoke-device-method --device-id <your device id> \
  --hub-name <your hub name> \
  --method-name <the method name> \
  --method-payload <the method payload>

Set a desired property interval = 3000 by running the following command:

az iot hub device-twin update -n <your hub name> \
  -d <your device id> --set properties.desired.interval=3000

This property can be read from your device.

Get the reported properties of the device by running the following command:

az iot hub device-twin show -n <your hub name> -d <your device id>

One of the twin reported properties is $metadata.$lastUpdated, which shows the last time the device app updated its reported property set.

Display the tags and properties of the device by running the following command:

az iot hub device-twin show --hub-name <your hub name> --device-id <your device id>

Add a field role = temperature&humidity to the device by running the following command:

az iot hub device-twin update \
  --hub-name <your hub name> \
  --device-id <your device id> \
  --set tags='{"role":"temperature&humidity"}'

Query devices with a tag of role = 'temperature&humidity' by running the following command:

az iot hub query --hub-name <your hub name> \
  --query-command "SELECT * FROM devices WHERE tags.role = 'temperature&humidity'"

Query all devices except those with a tag of role = 'temperature&humidity' by running the following command:

az iot hub query --hub-name <your hub name> \
  --query-command "SELECT * FROM devices WHERE tags.role != 'temperature&humidity'"

You've learned how to monitor device-to-cloud messages and send cloud-to-device messages between your IoT device and Azure IoT Hub.

To continue to get started with Azure IoT Hub and to explore all extended IoT scenarios, see the following:

• Manage cloud device messaging with the Azure IoT Hub extension for Visual Studio Code

• Manage devices with the Azure IoT Hub extension for Visual Studio Code

• Set up message routing

• Use a web app to visualize real-time sensor data from your IoT hub

• Use ​​Logic ​​Apps for remote monitoring and notifications