樹莓

Question

發送消息到Azure的IOT中心我需要從安裝在我的覆盆子一個通用的應用程序將消息發送到Azure的IOT中心（https://azure.microsoft.com/it-it/services/iot-hub/）。我必須使用HTTP協議，因爲樹莓不支持AMQP。 我使用下面的代碼：

public sealed partial class MainPage : Page 
{ 
    private DispatcherTimer _timer = null; 
    private DeviceClient _deviceClient = null; 
    private const string _deviceConnectionString = "<myConnectionString>"; 

    public MainPage() 
    { 
     InitializeComponent(); 

     _deviceClient = DeviceClient.CreateFromConnectionString(_deviceConnectionString, TransportType.Http1); 

     _timer = new DispatcherTimer(); 
     _timer.Interval = TimeSpan.FromSeconds(5); 
     _timer.Tick += _timer_Tick; 
     _timer.Start(); 
    } 

    private async void _timer_Tick(object sender, object e) 
    { 
     string msg = "{deviceId: 'myFirstDevice', timestamp: " + DateTime.Now.Ticks + " }"; 

     Message eventMessage = new Message(Encoding.UTF8.GetBytes(msg)); 
     await _deviceClient.SendEventAsync(eventMessage); 
    } 
} 

SendEventAsync給我：

Exception thrown: 'Microsoft.Azure.Devices.Client.Exceptions.IotHubCommunicationException' in mscorlib.ni.dll

Message: {"An error occurred while sending the request."} 

我已經包括在我的項目Microsoft.AspNet.WebApi.Client如下記載：https://github.com/Azure/azure-iot-sdks/issues/65沒有結果。

"dependencies": { 
    "Microsoft.AspNet.WebApi.Client": "5.2.3", 
    "Microsoft.Azure.Devices.Client": "1.0.0-preview-007", 
    "Microsoft.NETCore.UniversalWindowsPlatform": "5.0.0" 
}, 
"frameworks": { 
    "uap10.0": {} 
} 

如果我在控制檯應用程序中嘗試SAME代碼，它按預期工作。

Answer 1

搜索後幾個小時，我發現一個硬件問題。我的Raspberry試圖使用未配置的Wi-Fi適配器發送請求，而對於使用網絡電纜的所有其他請求。去掉加密狗的確有竅門。

Answer 2

@danvy是正確的，你需要生成一個SAS令牌，這裏是一個簽名生成https://github.com/sandrinodimattia/RedDog/releases

可能有多種方式發送事件，您正在使用HTTP，看看這個樣本

// Generate a SAS key with the Signature Generator.: 
var sas = "SharedAccessSignature sr=https%3a%2f%2freddogeventhub.servicebus.windows.net%2ftemperature%2fpublishers%2flivingroom%2fmessages&sig=I7n%2bqlIExBRs23V4mcYYfYVYhc6adOlMAeTY9VM9kNg%3d&se=1405562228&skn=SenderDevice"; 

// Namespace info. 
var serviceNamespace = "myeventhub"; 
var hubName = "temperature"; 
var deviceName = "livingroom"; 

// Create client. 
var httpClient = new HttpClient(); 
httpClient.BaseAddress = 
      new Uri(String.Format("https://{0}.servicebus.windows.net/", serviceNamespace)); 
httpClient.DefaultRequestHeaders 
      .TryAddWithoutValidation("Authorization", sas); 

Console.WriteLine("Starting device: {0}", deviceName); 

// Keep sending. 
while (true) 
{ 
    var eventData = new 
    { 
     Temperature = new Random().Next(20, 50) 
    }; 

    var postResult = httpClient.PostAsJsonAsync(
      String.Format("{0}/publishers/{1}/messages", hubName, deviceName), eventData).Result; 

    Console.WriteLine("Sent temperature using HttpClient: {0}", 
      eventData.Temperature); 
    Console.WriteLine(" > Response: {0}", 
      postResult.StatusCode); 
    Console.WriteLine(" > Response Content: {0}", 
      postResult.Content.ReadAsStringAsync().Result); 

    Thread.Sleep(new Random().Next(1000, 5000)); 
} 

看看這篇文章瞭解更多詳情http://fabriccontroller.net/iot-with-azure-service-bus-event-hubs-authenticating-and-sending-from-any-type-of-device-net-and-js-samples/

Answer 3

嘗試連接字符串設定爲您的設備（_deviceConnectionString）使用本教程

https://github.com/Azure/azure-iot-sdks/blob/master/tools/DeviceExplorer/doc/how_to_use_device_explorer.md

你可以手工使用從物聯網中心獲得直接或通過物聯網套房嚮導創建的儀表盤的信息做到這一點。它看起來像這樣

_deviceConnectionString =「HostName = YourIoTHubName.azure-devices.net; DeviceId = YourDeviceId; SharedAccessKey = YourDeviceSharedAccessKey」;

Answer 4

你生成使用CreateDeviceIdentity工具，設備ID和設備密鑰是否正確？ 下面是指南：https://blogs.windows.com/buildingapps/2015/12/09/windows-iot-core-and-azure-iot-hub-putting-the-i-in-iot/