ios - 如何使用azure iot sdk在ios中调用设备方法

Question

我正在尝试使用连接字符串调用与设备关联的方法。我尝试使用其他语言提供的示例，我能够在设备中调用该方法。例如:灯的“setState”或“getState”。但是我无法使用 swift 在 iOS 中实现。

我尝试通过引用C示例来匹配parameter参数要求。但我越来越1. Func:sendHttpRequestDeviceMethod Line:337 Http 失败状态代码 400。2. Func:IoTHubDeviceMethod_Invoke Line:492 为设备方法调用发送HTTP请求失败

     var status :Int32! = 0
     var deviceId = "simulated_device_one";
     var  methodName = "GetState";
    var uint8Pointer:UnsafeMutablePointer<UInt8>!
    uint8Pointer = UnsafeMutablePointer<UInt8>.allocate(capacity:8)

    var size = size_t(10000)
    var bytes: [UInt8] = [39, 77, 111, 111, 102, 33, 39, 0]
    uint8Pointer?.initialize(from: &bytes, count: 8)
    var intValue : UnsafeMutablePointer<UInt8>?
    intValue = UnsafeMutablePointer(uint8Pointer)
    var char: UInt8 =  UInt8(20)
    var charPointer = UnsafeMutablePointer<UInt8>(&char)
    var prediction = intValue
    let serviceClientDeviceMethodHandle =  IoTHubDeviceMethod_Create(service_client_handle)

    let payLoad = "test"

    var responsePayload = ""


    let invoke = IoTHubDeviceMethod_Invoke(serviceClientDeviceMethodHandle, deviceId, methodName, payLoad , 100, &status, &prediction,&size )

我想使用 IoTHubDeviceMethod_Invoke 在设备中调用一个方法

Answer 1

您可以下载我处理过的 View Controller 文件 from here

1.Create Connection in view did load

// declaring your connection string you can find it in azure iot dashboard
private let connectionString = "Enter your connection String";


// creating service handler 
private var service_client_handle: IOTHUB_SERVICE_CLIENT_AUTH_HANDLE!;


// handler for the method invoke   
private var iot_device_method_handle:IOTHUB_SERVICE_CLIENT_DEVICE_METHOD_HANDLE!;



// In view did load establish the connection
service_client_handle = IoTHubServiceClientAuth_CreateFromConnectionString(connectionString)

if (service_client_handle == nil) {
    showError(message: "Failed to create IoT Service handle", sendState: false)
}

1. 创建方法调用函数

我是根据提供的发送消息的demo创建的

func openIothubMethodInvoke() -> Bool
{
    print("In openIotHub method invoke")
    let result: Bool;
    iot_device_method_handle = IoTHubDeviceMethod_Create(service_client_handle);
    let testValue : Any? = iot_device_method_handle;
    if (testValue == nil) {
        showError(message: "Failed to create IoT devicemethod", sendState: false);
        result = false;
    }
    else
    {
        result = true;
    }
    return result;
}

1. 调用方法调用

** 这是调用方法的主要功能

func methodInvoke()
    {
        let testValue : Any? = iot_device_method_handle;
        if (testValue == nil && !openIothubMethodInvoke() ) {
            print("Failued to open IoThub messaging");
        }
        else {
            let size = UnsafeMutablePointer<Int>.allocate(capacity: 1)
            let responseStatus = UnsafeMutablePointer<Int32>.allocate(capacity: 1)
      // Payload is the main change it is like specifying the format
            var payload = UnsafeMutablePointer<UnsafeMutablePointer<UInt8>?>.allocate(capacity: 1)
            // if  payload is not expected please send empty json "{}"
            let result = IoTHubDeviceMethod_Invoke(iot_device_method_handle, "nameOfTheDeviceYouWantToCallOn", "MethodName", "{payload you want to send}", 100, responseStatus, payload , size)
      //  extracting the data from response
            let b = UnsafeMutableBufferPointer(start: payload.pointee, count:  size.pointee)

            let data = Data(buffer: b)

           let str = String(bytes: data, encoding: .utf8)
            print(str)
            do{
                let value = try JSONSerialization.jsonObject(with: data, options: .allowFragments)
                  print(value)
            }catch{
                print(error)
            }
        }
    }