快速入门:使用 Node.js 控制连接到 Azure IoT 中心的设备Quickstart: Use Node.js to control a device connected to an Azure IoT hub

在本快速入门中,会使用直接方法来控制连接到 Azure IoT 中心的模拟设备。In this quickstart, you use a direct method to control a simulated device connected to Azure IoT Hub. IoT 中心是一项 Azure 服务,使你可以从云管理 IoT 设备,并将大量设备遥测引入云以进行存储或处理。IoT Hub is an Azure service that enables you to manage your IoT devices from the cloud, and ingest high volumes of device telemetry to the cloud for storage or processing. 可使用直接方法远程更改连接到 IoT 中心的设备的行为。You can use direct methods to remotely change the behavior of a device connected to your IoT hub. 本快速入门使用两个 Node.js 应用程序:一个是模拟设备应用程序,用于响应从后端应用程序调用的直接方法;另一个是后端应用程序,用于在模拟设备上调用直接方法。This quickstart uses two Node.js applications: a simulated device application that responds to direct methods called from a back-end application and a back-end application that calls the direct methods on the simulated device.


  • 具有活动订阅的 Azure 帐户。An Azure account with an active subscription. 创建试用帐户Create trial.

  • Node.js 10+Node.js 10+.

    可以使用以下命令验证开发计算机上 Node.js 当前的版本:You can verify the current version of Node.js on your development machine using the following command:

    node --version
  • 一个示例 Node.js 项目A sample Node.js project.

  • 端口 8883 在防火墙中处于打开状态。Port 8883 open in your firewall. 本快速入门中的设备示例使用 MQTT 协议,该协议通过端口 8883 进行通信。The device sample in this quickstart uses MQTT protocol, which communicates over port 8883. 在某些公司和教育网络环境中,此端口可能被阻止。This port may be blocked in some corporate and educational network environments. 有关解决此问题的更多信息和方法,请参阅连接到 IoT 中心(MQTT)For more information and ways to work around this issue, see Connecting to IoT Hub (MQTT).

  • 如果需要,请安装 Azure CLI 来运行 CLI 参考命令。If you prefer, install the Azure CLI to run CLI reference commands.
    • 如果使用的是本地安装,请使用 az login 命令登录到 Azure CLI。If you're using a local installation, sign in to the Azure CLI by using the az login command. 若要完成身份验证过程,请遵循终端中显示的步骤。To finish the authentication process, follow the steps displayed in your terminal. 有关其他登录选项,请参阅登录 Azure CLIFor additional sign-in options, see Sign in with the Azure CLI.
    • 出现提示时,请在首次使用时安装 Azure CLI 扩展。When you're prompted, install Azure CLI extensions on first use. 有关扩展详细信息,请参阅使用 Azure CLI 的扩展For more information about extensions, see Use extensions with the Azure CLI.
    • 运行 az version 以查找安装的版本和依赖库。Run az version to find the version and dependent libraries that are installed. 若要升级到最新版本,请运行 az upgradeTo upgrade to the latest version, run az upgrade.


本文使用最新版本的 Azure IoT 扩展(称为 azure-iot)。This article uses the newest version of the Azure IoT extension, called azure-iot. 旧版本称为 azure-iot-cli-ext。只应同时安装有一个版本。The legacy version is called azure-iot-cli-ext.You should only have one version installed at a time. 可以使用命令 az extension list 来验证当前安装的扩展。You can use the command az extension list to validate the currently installed extensions.

使用 az extension remove --name azure-cli-iot-ext 可删除扩展的旧版本。Use az extension remove --name azure-cli-iot-ext to remove the legacy version of the extension.

使用 az extension add --name azure-iot 可添加扩展的新版本。Use az extension add --name azure-iot to add the new version of the extension.

若要查看已安装了哪些扩展,请使用 az extension listTo see what extensions you have installed, use az extension list.

创建 IoT 中心Create an IoT hub

如果已完成上一快速入门:将遥测数据从设备发送到 IoT 中心,则可以跳过此步骤。If you completed the previous Quickstart: Send telemetry from a device to an IoT hub, you can skip this step.

此部分介绍如何使用 Azure 门户创建 IoT 中心。This section describes how to create an IoT hub using the Azure portal.

  1. 登录到 Azure 门户Sign in to the Azure portal.

  2. 从 Azure 主页中选择“+ 创建资源”按钮,然后在“搜索市场”字段中输入“IoT 中心”。 From the Azure homepage, select the + Create a resource button, and then enter IoT Hub in the Search the Marketplace field.

  3. 在搜索结果中选择“IoT 中心”,然后选择“创建” 。Select IoT Hub from the search results, and then select Create.

  4. 在“基本信息”选项卡上,按如下所示填写字段: On the Basics tab, complete the fields as follows:

    • 订阅:选择要用于中心的订阅。Subscription: Select the subscription to use for your hub.

    • 资源组:选择一个资源组或新建一个资源组。Resource Group: Select a resource group or create a new one. 若要新建资源组,请选择“新建”并填写要使用的名称。 To create a new one, select Create new and fill in the name you want to use. 若要使用现有的资源组,请选择它。To use an existing resource group, select that resource group. 有关详细信息,请参阅管理 Azure 资源管理器资源组For more information, see Manage Azure Resource Manager resource groups.

    • 区域:选择中心所在的区域。Region: Select the region in which you want your hub to be located. 选择最靠近你的位置。Select the location closest to you.

    • IoT 中心名称:输入中心的名称。IoT Hub Name: Enter a name for your hub. 此名称必须全局唯一。This name must be globally unique. 如果输入的名称可用,会显示一个绿色复选标记。If the name you enter is available, a green check mark appears.


    IoT 中心将公开为 DNS 终结点,因此,命名时请务必避免包含任何敏感信息。The IoT hub will be publicly discoverable as a DNS endpoint, so make sure to avoid any sensitive information while naming it.

    在 Azure 门户中创建中心

  5. 在完成时选择“下一步: 大小和规模”,以继续创建中心。Select Next: Size and scale to continue creating your hub.

    使用 Azure 门户为新的中心设置大小和规模

    可在此处接受默认设置。You can accept the default settings here. 如果需要,可以修改以下任何字段:If desired, you can modify any of the following fields:

    • 定价和缩放层:选择的层。Pricing and scale tier: Your selected tier. 可以根据你需要的功能数以及每天通过解决方案发送的消息数从多个层级中进行选择。You can choose from several tiers, depending on how many features you want and how many messages you send through your solution per day. 免费层适用于测试和评估。The free tier is intended for testing and evaluation. 允许 500 台设备连接到中心,每天最多可传输 8,000 条消息。It allows 500 devices to be connected to the hub and up to 8,000 messages per day. 每个 Azure 订阅可以在免费层中创建一个 IoT 中心。Each Azure subscription can create one IoT hub in the free tier.

      如果正在完成 IoT 中心设备流的快速入门,请选择免费层。If you are working through a Quickstart for IoT Hub device streams, select the free tier.

    • IoT 中心单元:每个单位每日允许的消息数取决于中心的定价层。IoT Hub units: The number of messages allowed per unit per day depends on your hub's pricing tier. 例如,如果希望中心支持 700,000 条消息引入,请选择两个 S1 层单位。For example, if you want the hub to support ingress of 700,000 messages, you choose two S1 tier units. 有关其他层选项的详细信息,请参阅选择合适的 IoT 中心层For details about the other tier options, see Choosing the right IoT Hub tier.

    • 高级设置 > 设备到云的分区:此属性将设备到云消息与这些消息的同步读取器数目相关联。Advanced Settings > Device-to-cloud partitions: This property relates the device-to-cloud messages to the number of simultaneous readers of the messages. 大多数中心只需要 4 个分区。Most hubs need only four partitions.

  6. 在完成时选择“下一步: 标记”继续到下一屏幕。Select Next: Tags to continue to the next screen.

    标记是名称/值对。Tags are name/value pairs. 可以为多个资源和资源组分配相同的标记,以便对资源进行分类并合并计费。You can assign the same tag to multiple resources and resource groups to categorize resources and consolidate billing. 有关详细信息,请参阅使用标记来组织 Azure 资源for more information, see Use tags to organize your Azure resources.

    使用 Azure 门户为新的中心设置大小和规模

  7. 在完成时选择“下一步: 查看+创建”可查看选择。Select Next: Review + create to review your choices. 你会看到类似于此屏幕的内容,但其中包含创建中心时选择的值。You see something similar to this screen, but with the values you selected when creating the hub.


  8. 选择“创建”以创建新的中心 。Select Create to create your new hub. 创建中心需要几分钟时间。Creating the hub takes a few minutes.

注册设备Register a device

如果已完成上一快速入门:将遥测数据从设备发送到 IoT 中心,则可以跳过此步骤。If you completed the previous Quickstart: Send telemetry from a device to an IoT hub, you can skip this step.

必须先将设备注册到 IoT 中心,然后该设备才能进行连接。A device must be registered with your IoT hub before it can connect. 在本快速入门中,请使用 Azure CLI 来注册模拟设备。In this quickstart, you use the Azure CLI to register a simulated device.

  1. 运行以下命令,以创建设备标识。Run the following command to create the device identity.

    YourIoTHubName:将下面的占位符替换为你为 IoT 中心选择的名称。YourIoTHubName : Replace this placeholder below with the name you chose for your IoT hub.

    MyNodeDevice:这是所注册的设备的名称。MyNodeDevice: This is the name of the device you're registering. 建议使用 MyNodeDevice,如图所示。It's recommended to use MyNodeDevice as shown. 如果为设备选择不同名称,则可能还需要在本文中从头至尾使用该名称,并在运行示例应用程序之前在其中更新设备名称。If you choose a different name for your device, you also need to use that name throughout this article, and update the device name in the sample applications before you run them.

    az iot hub device-identity create \
      --hub-name {YourIoTHubName} --device-id MyNodeDevice
  2. 运行以下命令,获取刚注册设备的 设备连接字符串Run the following commands to get the device connection string for the device you just registered:

    YourIoTHubName:将下面的占位符替换为你为 IoT 中心选择的名称。YourIoTHubName : Replace this placeholder below with the name you chose for your IoT hub.

    az iot hub device-identity show-connection-string \
      --hub-name {YourIoTHubName} \
      --device-id MyNodeDevice \
      --output table

    记下如下所示的设备连接字符串:Make a note of the device connection string, which looks like:


    稍后会在快速入门中用到此值。You use this value later in the quickstart.

  3. 还需一个服务连接字符串,以便后端应用程序能够连接到 IoT 中心并检索消息 。You also need a service connection string to enable the back-end application to connect to your IoT hub and retrieve the messages. 以下命令检索 IoT 中心的服务连接字符串:The following command retrieves the service connection string for your IoT hub:

    YourIoTHubName:将下面的占位符替换为你为 IoT 中心选择的名称。YourIoTHubName : Replace this placeholder below with the name you chose for your IoT hub.

    az iot hub show-connection-string \
      --policy-name service --name {YourIoTHubName} --output table

    记下如下所示的服务连接字符串:Make a note of the service connection string, which looks like:


    稍后会在快速入门中用到此值。You use this value later in the quickstart. 此服务连接字符串与你在上一步中记录的设备连接字符串不同。This service connection string is different from the device connection string you noted in the previous step.

侦听直接方法调用Listen for direct method calls

模拟设备应用程序会连接到 IoT 中心上特定于设备的终结点,发送模拟遥测数据,并侦听中心的直接方法调用。The simulated device application connects to a device-specific endpoint on your IoT hub, sends simulated telemetry, and listens for direct method calls from your hub. 在本快速入门中,中心的直接方法调用告知设备对其发送遥测的间隔进行更改。In this quickstart, the direct method call from the hub tells the device to change the interval at which it sends telemetry. 执行直接方法后,模拟设备会将确认发送回中心。The simulated device sends an acknowledgement back to your hub after it executes the direct method.

  1. 在本地终端窗口中,导航到示例 Node.js 项目的根文件夹。In a local terminal window, navigate to the root folder of the sample Node.js project. 然后导航到 iot-hub\Quickstarts\simulated-device-2 文件夹。Then navigate to the iot-hub\Quickstarts\simulated-device-2 folder.

  2. 在所选文本编辑器中打开 SimulatedDevice.js 文件 。Open the SimulatedDevice.js file in a text editor of your choice.

    connectionString 变量的值替换为之前记下的设备连接字符串。Replace the value of the connectionString variable with the device connection string you made a note of earlier. 然后将更改保存到 SimulatedDevice.jsThen save your changes to SimulatedDevice.js.

  3. 在本地终端窗口中,运行以下命令以安装所需的库,并运行模拟设备应用程序:In the local terminal window, run the following commands to install the required libraries and run the simulated device application:

    npm install
    node SimulatedDevice.js

    以下屏幕截图显示了模拟设备应用程序将遥测数据发送到 IoT 中心后的输出:The following screenshot shows the output as the simulated device application sends telemetry to your IoT hub:


调用直接方法Call the direct method

后端应用程序会连接到 IoT 中心上的服务端终结点。The back-end application connects to a service-side endpoint on your IoT Hub. 应用程序通过 IoT 中心对设备进行直接方法调用,并侦听确认。The application makes direct method calls to a device through your IoT hub and listens for acknowledgements. IoT 中心后端应用程序通常在云中运行。An IoT Hub back-end application typically runs in the cloud.

  1. 在另一个本地终端窗口中,导航到示例 Node.js 项目的根文件夹。In another local terminal window, navigate to the root folder of the sample Node.js project. 然后导航到 iot-hub\Quickstarts\back-end-application 文件夹 。Then navigate to the iot-hub\Quickstarts\back-end-application folder.

  2. 在所选文本编辑器中打开 BackEndApplication.js 文件 。Open the BackEndApplication.js file in a text editor of your choice.

    connectionString 变量的值替换为以前记下的服务连接字符串。Replace the value of the connectionString variable with the service connection string you made a note of earlier. 然后将更改保存到 BackEndApplication.jsThen save your changes to BackEndApplication.js.

  3. 在本地终端窗口中运行以下命令,以安装所需的库并运行后端应用程序:In the local terminal window, run the following commands to install the required libraries and run the back-end application:

    npm install
    node BackEndApplication.js

    以下屏幕截图显示了应用程序对设备进行直接方法调用并接收确认后的输出:The following screenshot shows the output as the application makes a direct method call to the device and receives an acknowledgement:


    运行后端应用程序后,在运行模拟设备的控制台窗口中会出现一条消息,且其发送消息的速率也会发生变化:After you run the back-end application, you see a message in the console window running the simulated device, and the rate at which it sends messages changes:


清理资源Clean up resources

如果想要继续学习下一篇建议的文章,可以保留已创建的资源,以便重复使用。If you will be continuing to the next recommended article, you can keep the resources you've already created and reuse them.

否则,可删除本文中创建的 Azure 资源,避免收费。Otherwise, you can delete the Azure resources created in this article to avoid charges.


删除资源组的操作不可逆。Deleting a resource group is irreversible. 资源组以及包含在其中的所有资源将被永久删除。The resource group and all the resources contained in it are permanently deleted. 请确保不会意外删除错误的资源组或资源。Make sure that you do not accidentally delete the wrong resource group or resources. 如果在现有的包含要保留资源的资源组中创建了 IoT 中心,则只删除 IoT 中心资源本身,而不要删除资源组。If you created the IoT Hub inside an existing resource group that contains resources you want to keep, only delete the IoT Hub resource itself instead of deleting the resource group.

若要按名称删除资源组,请执行以下操作:To delete a resource group by name:

  1. 登录到 Azure 门户,然后选择“资源组”。 Sign in to the Azure portal and select Resource groups.

  2. 在“按名称筛选”文本框中,键入包含 IoT 中心的资源组的名称 。In the Filter by name textbox, type the name of the resource group containing your IoT Hub.

  3. 在结果列表中的资源组右侧,选择“...”,然后选择“删除资源组” 。To the right of your resource group in the result list, select ... then Delete resource group.


  4. 系统会要求确认是否删除资源组。You will be asked to confirm the deletion of the resource group. 再次键入资源组的名称进行确认,然后选择“删除” 。Type the name of your resource group again to confirm, and then select Delete. 片刻之后,将会删除该资源组及其包含的所有资源。After a few moments, the resource group and all of its contained resources are deleted.

后续步骤Next steps

在本快速入门中,已从后端应用程序调用了设备上的直接方法,并在模拟设备应用程序中响应了直接方法调用。In this quickstart, you called a direct method on a device from a back-end application, and responded to the direct method call in a simulated device application.

若要了解如何将设备到云的消息路由到云中的不同目标,请继续学习下一教程。To learn how to route device-to-cloud messages to different destinations in the cloud, continue to the next tutorial.