/// <summary>
/// Get the last Response saved on DB cache for a given method and payload
/// </summary>
/// <param name="device"></param>
/// <param name="method"></param>
/// <param name="payload"></param>
/// <param name="db"></param>
/// <returns></returns>
public string GetResponseFromCache(IoTDevice device, IoTDeviceMethod method, string payload, Database db = null)
{
if (method == null)
{
return(string.Empty);
}
db = GetDatabase(db);
if (db == null)
{
return(string.Empty);
}
var key = GetMethodKey(device, method, payload);
if (string.IsNullOrEmpty(key))
{
return(string.Empty);
}
// Retrieve and return saved value
var savedValue = db.PropertyStore.GetStringValue(key);
return(savedValue);
}
/// <summary>
/// Deserialize and Parse a string using Deserializer from the giving method
/// </summary>
/// <param name="method"></param>
/// <param name="response"></param>
/// <returns></returns>
public static DynamicMessage DeserializeAndParse(IoTDeviceMethod method, string response)
{
// Get returnType and deserializer
var returnType = method.GetMessageType();
if (returnType == null)
{
Log.Error($"Method {method.ID} has an invalid Return Type", typeof(IoTDeviceMethod));
return(null);
}
var deserializer = returnType.GetDeserializer();
if (deserializer == null)
{
Log.Error($"Message Type {returnType.ID} has an invalid Deserializer",
typeof(IoTDeviceMethod));
return(null);
}
// Instantiate Deserializer object
var deserializerObject = deserializer.GetDeserializerObject();
if (deserializerObject == null)
{
return(null);
}
// Parse results
var parsedDictionary = (DynamicMessage)deserializerObject.Deserialize(response);
parsedDictionary.RawMessage = response;
return(parsedDictionary);
}
/// <summary>
/// Invoke a given Method passing optional payload
/// </summary>
/// <param name="device"></param>
/// <param name="method"></param>
/// <param name="payload"></param>
/// <returns></returns>
public static DynamicMessage InvokeMethod(IoTDevice device, IoTDeviceMethod method, string payload = "")
{
var hub = device.GetHub();
var connectionStringsServer = hub.ConnectionString;
var parsedDictionary =
InvokeMethodInternal(device, method, connectionStringsServer, payload).GetAwaiter().GetResult();
return(parsedDictionary);
}
private static string GetMethodKey(IoTDevice device, IoTDeviceMethod method, string payload)
{
var sb = new StringBuilder();
sb.Append(device.ID);
sb.Append("_");
sb.Append(method.ID);
sb.Append("_");
sb.Append(GetMd5(payload));
return(sb.ToString());
}
public IoTDevice GetDeviceAndMethodByName(string deviceMethodName, out IoTDeviceMethod method, Database database = null)
{
var device = GetDeviceByName(deviceMethodName, database);
if (device == null)
{
method = null;
return(null);
}
method = GetMethodByName(deviceMethodName, database);
return(device);
}
/// <summary>
/// Save response to DB cache for a given method and payload
/// </summary>
/// <param name="device"></param>
/// <param name="method"></param>
/// <param name="payload"></param>
/// <param name="response"></param>
/// <param name="db"></param>
public void SaveResponseToCache(IoTDevice device, IoTDeviceMethod method, string payload, string response, Database db = null)
{
if (method == null)
{
return;
}
db = GetDatabase(db);
if (db == null)
{
return;
}
var key = GetMethodKey(device, method, payload);
if (string.IsNullOrEmpty(key))
{
return;
}
// Save value to DB
db.PropertyStore.SetStringValue(key, response);
}
public SmartDisplayController(IIoTHubRepository ioTHubRepository)
{
_method = ioTHubRepository.GetMethodByName(MethodPath);
_device = ioTHubRepository.GetDeviceByName(MethodPath);
}
/// <summary>
/// Internal Invoke method call
/// </summary>
/// <param name="device"></param>
/// <param name="method"></param>
/// <param name="connectionStringsServer"></param>
/// <param name="payload"></param>
/// <returns></returns>
private static async Task <DynamicMessage> InvokeMethodInternal(IoTDevice device, IoTDeviceMethod method,
string connectionStringsServer, string payload = "")
{
var methodInvocation = new CloudToDeviceMethod(method.MethodName)
{
ResponseTimeout = TimeSpan.FromSeconds(30)
};
// Payload to send
if (!string.IsNullOrEmpty(payload))
{
methodInvocation.SetPayloadJson(JsonConvert.SerializeObject(payload));
}
// Invoke the direct method asynchronously and get the response from the device.
var serviceClient = ServiceClient.CreateFromConnectionString(connectionStringsServer);
CloudToDeviceMethodResult response;
try
{
response = serviceClient.InvokeDeviceMethodAsync(device.DeviceName, methodInvocation).GetAwaiter().GetResult();
}
catch (Exception e)
{
Log.Warn($"Error calling method '{method.ID}' on device '{device.ID}' - Error: {e.Message}",
typeof(IoTDeviceMethod));
return(new DynamicMessage());
}
// Resulting Payload
var receivedPayload = response.GetPayloadAsJson();
// Log results
Log.Info($"Response status: {response.Status}, payload:", typeof(IoTDeviceMethod));
Log.Info(receivedPayload, typeof(IoTDeviceMethod));
// Deserialize
var result = DeserializeAndParse(method, receivedPayload);
return(result);
}
