Question

我正在尝试设置一个小的IoT Hub应用程序来测试平台是否能够满足我的要求。我需要将数据从设备上传到云，并将命令从云下载到设备。我正在关注这个简单的例子：

Creating Azure IoT Edge Custom Modules in C# – send and receive data from IoT Hub

我从GitHub (linked in the previous tutorial)下载了源代码并修改了.Net solution。我创建了一个免费的（F1）Iot Hub并添加了一个设备。这些是我对源代码所做的更改：

传感器每5分钟发送一次消息，而不是5秒钟。
收到的消息以不同的格式打印在控制台上，写入属性。
我在module_dev_sample.json文件中编写了更改（在教程之后）。

以下是完整的源代码：

DotNetSensorModule.cs

public class DotNetSensorModule : IGatewayModule, IGatewayModuleStart
{
    private Broker broker;
    private string configuration;

    public void Create(Broker broker, byte[] configuration)
    {
        this.broker = broker;
        this.configuration = Encoding.UTF8.GetString(configuration);
    }

    public void Start()
    {
        Thread oThread = new Thread(new ThreadStart(this.threadBody));
        // Start the thread
        oThread.Start();
    }

    public void Destroy() { }

    public void Receive(Message received_message)
    {
        string content = Encoding.UTF8.GetString(received_message.Content, 0, received_message.Content.Length);
        Console.WriteLine($"{DateTime.Now.ToString("HH:mm:ss")} Somewhere to Sensor message. Content: {content}");
        if (received_message.Properties.Count > 0)
        {
            Console.WriteLine("    Properties:");
            foreach (KeyValuePair<string, string> property in received_message.Properties)
                Console.WriteLine($"        {property.Key}: {property.Value}");
        }
    }

    public void threadBody()
    {
        Random r = new Random();
        int n = r.Next();

        while (true)
        {
            Dictionary<string, string> thisIsMyProperty = new Dictionary<string, string>();
            thisIsMyProperty.Add("source", "mapping");
            thisIsMyProperty.Add("deviceName", "my-device-name");
            thisIsMyProperty.Add("deviceKey", "my-device-key");

            Message messageToPublish = new Message("SensorData: " + n, thisIsMyProperty);
            this.broker.Publish(messageToPublish);
            //Publish a message every 5 minutes. 
            Thread.Sleep(300000);
            n = r.Next();
        }
    }
}

DotNetPrinterModule.cs

public class DotNetPrinterModule : IGatewayModule
{
    private string configuration;
    public void Create(Broker broker, byte[] configuration)
    {
        this.configuration = Encoding.UTF8.GetString(configuration);
    }

    public void Destroy() { }

    public void Receive(Message received_message)
    {
        string content = Encoding.UTF8.GetString(received_message.Content, 0, received_message.Content.Length);
        if (received_message.Properties["source"] == "mapping")
        {
            Console.WriteLine($"{DateTime.Now.ToString("HH:mm:ss")} Sensor to Printer message. Content: {content}");
        }
        else
        {
            Console.WriteLine($"{DateTime.Now.ToString("HH:mm:ss")} Somewhere to Printer message. Content: {content}");
        }
        if (received_message.Properties.Count > 0)
        {
            Console.WriteLine("    Properties:");
            foreach (KeyValuePair<string, string> property in received_message.Properties)
                Console.WriteLine($"        {property.Key}: {property.Value}");
        }
    }
}

module_dev_sample.json

{
  "modules": [
    {
      "name": "IotHub",
      "loader": {
        "name": "native",
        "entrypoint": {
          "module.path": "iothub.dll"
        }
      },
      "args": {
        "IoTHubName": "my-free-iot-hub",
        "IoTHubSuffix": "azure-devices.net",
        "Transport": "HTTP"
      }
    },
    {
      "name": "dotnet_sensor_module",
      "loader": {
        "name": "dotnet",
        "entrypoint": {
          "assembly.name": "DotNetModuleSample",
          "entry.type": "SensorModule.DotNetSensorModule"
        }
      },
      "args": "module configuration"
    },
    {
      "name": "dotnet_printer_module",
      "loader": {
        "name": "dotnet",
        "entrypoint": {
          "assembly.name": "DotNetModuleSample",
          "entry.type": "PrinterModule.DotNetPrinterModule"
        }
      },
      "args": "module configuration"
    }
  ],
  "links": [
    {
      "source": "dotnet_sensor_module",
      "sink": "dotnet_printer_module"
    },
    {
      "source": "dotnet_sensor_module",
      "sink": "IotHub"
    },
    {
      "source": "IotHub",
      "sink": "dotnet_sensor_module"
    }
  ]
}

当我运行应用程序时，我可以读取发送的消息。此外，我可以在Azure门户上看到IoT Hub的消息计数器是如何递增的。但是当我使用设备资源管理器发送消息时，我没有看到消息已收到。 有时会在10分钟，25分钟或50分钟后收到消息，有时会丢失消息。如果我在邮件中添加任何属性，则可以确定它不会被收到。你知道为什么会这样吗？

谢谢。

修改

我注意到如果我从Device Explorer连续发送10条消息，每次运行应用程序时，都会立即收到其中一条消息。我不知道为什么。

IoT Hub Edge：C2D消息延迟超过25分钟

0 个答案: