✨ The client app can receiving device twin message (Azure-Samples#4)

* Fix readme

* fix mirrot

* Update main.c

* Update main.c

* twins

* parse the interval value

* I can change the interval of sending message

* the receiving message is only the desired part

* Update LogInfor

* change printf to log

* Update config.h

Author: yuwzho

.gitignore

@@ -8,6 +8,16 @@
 *.gch
 *.pch
 
+# vim temp
+*.swp
+
+#cmake file
+CMakeCache.txt
+CMakeFiles/
+Makefile
+app
+cmake_install.cmake
+
 # Libraries
 *.lib
 *.a

main.c

@@ -13,7 +13,7 @@
 #include <iothub_client_options.h>
 #include <iothub_message.h>
 #include <iothubtransportmqtt.h>
-
+#include <jsondecoder.h>
 #include "./config.h"
 #include "./wiring.h"
 
@@ -23,6 +23,8 @@ const char *notFound = "\"No method found\"";
 static bool messagePending = false;
 static bool sendingMessage = true;
 
+static int interval = INTERVAL;
+
 static void sendCallback(IOTHUB_CLIENT_CONFIRMATION_RESULT result, void *userContextCallback)
 {
     if (IOTHUB_CLIENT_CONFIRMATION_OK == result)
@@ -31,7 +33,7 @@ static void sendCallback(IOTHUB_CLIENT_CONFIRMATION_RESULT result, void *userCon
     }
     else
     {
-        (void)printf("Failed to send message to Azure IoT Hub\r\n");
+        LogError("Failed to send message to Azure IoT Hub");
     }
 
     messagePending = false;
@@ -42,21 +44,21 @@ static void sendMessages(IOTHUB_CLIENT_LL_HANDLE iotHubClientHandle, char *buffe
     IOTHUB_MESSAGE_HANDLE messageHandle = IoTHubMessage_CreateFromByteArray(buffer, strlen(buffer));
     if (messageHandle == NULL)
     {
-        (void)printf("Unable to create a new IoTHubMessage\r\n");
+        LogError("Unable to create a new IoTHubMessage");
     }
     else
     {
         MAP_HANDLE properties = IoTHubMessage_Properties(messageHandle);
         Map_Add(properties, "temperatureAlert", (temperatureAlert > 0) ? "true" : "false");
-        (void)printf("Sending message: %s\r\n", buffer);
+        LogInfo("Sending message: %s", buffer);
         if (IoTHubClient_LL_SendEventAsync(iotHubClientHandle, messageHandle, sendCallback, NULL) != IOTHUB_CLIENT_OK)
         {
-            (void)printf("Failed to send message to Azure IoT Hub\r\n");
+            LogError("Failed to send message to Azure IoT Hub");
         }
         else
         {
             messagePending = true;
-            (void)printf("Message sent to Azure IoT Hub\r\n");
+            LogInfo("Message sent to Azure IoT Hub");
         }
 
         IoTHubMessage_Destroy(messageHandle);
@@ -100,7 +102,7 @@ int deviceMethodCallback(
     size_t *response_size,
     void *userContextCallback)
 {
-    (void)printf("Try to invoke method %s\r\n", methodName);
+    LogInfo("Try to invoke method %s\r\n", methodName);
     const char *responseMessage = onSuccess;
     int result = 200;
 
@@ -114,7 +116,7 @@ int deviceMethodCallback(
     }
     else
     {
-        (void)printf("No method %s found\r\n", methodName);
+        LogError("No method %s found\r\n", methodName);
         responseMessage = notFound;
         result = 404;
     }
@@ -126,6 +128,39 @@ int deviceMethodCallback(
     return result;
 }
 
+void twinCallback(
+    DEVICE_TWIN_UPDATE_STATE updateState,
+    const unsigned char *payLoad,
+    size_t size,
+    void *userContextCallback)
+{
+    char *temp = (char *)malloc(size + 1);
+    for (int i = 0; i < size; i++)
+    {
+        temp[i] = (char)(payLoad[i]);
+    }
+    temp[size] = '\0';
+    MULTITREE_HANDLE tree = NULL;
+
+    if (JSON_DECODER_OK == JSONDecoder_JSON_To_MultiTree(temp, &tree))
+    {
+        MULTITREE_HANDLE child = NULL;
+
+        if (MULTITREE_OK != MultiTree_GetChildByName(tree, "desired", &child))
+        {
+            LogInfo("This device twin message contains desired message only");
+            child = tree;
+        }
+        const void *value = NULL;
+        if (MULTITREE_OK == MultiTree_GetLeafValue(child, "interval", &value))
+        {
+            interval = atoi((const char *)value);
+        }
+    }
+    MultiTree_Destroy(tree);
+    free(temp);
+}
+
 IOTHUBMESSAGE_DISPOSITION_RESULT receiveMessageCallback(IOTHUB_MESSAGE_HANDLE message, void *userContextCallback)
 {
     const unsigned char *buffer = NULL;
@@ -147,7 +182,7 @@ IOTHUBMESSAGE_DISPOSITION_RESULT receiveMessageCallback(IOTHUB_MESSAGE_HANDLE me
     strncpy(temp, buffer, size);
     temp[size] = '\0';
 
-    printf("Receiving message: %s\r\n", temp);
+    (void)printf("Receiving message: %s\r\n", temp);
     free(temp);
 
     return IOTHUBMESSAGE_ACCEPTED;
@@ -163,7 +198,7 @@ static char *readFile(char *fileName)
 
     if (fp == NULL)
     {
-        (void)printf("ERROR: File %s doesn't exist!\n", fileName);
+        LogError("ERROR: File %s doesn't exist!", fileName);
         return NULL;
     }
 
@@ -177,7 +212,7 @@ static char *readFile(char *fileName)
     if (buffer == NULL)
     {
         fclose(fp);
-        (void)printf("ERROR: Failed to allocate memory.\n");
+        LogError("ERROR: Failed to allocate memory.");
         return NULL;
     }
 
@@ -186,7 +221,7 @@ static char *readFile(char *fileName)
     {
         fclose(fp);
         free(buffer);
-        (void)printf("ERROR: Failed to read the file %s into memory.\n", fileName);
+        LogError("ERROR: Failed to read the file %s into memory.", fileName);
         return NULL;
     }
 
@@ -212,7 +247,7 @@ static bool setX509Certificate(IOTHUB_CLIENT_LL_HANDLE iotHubClientHandle, char
         IoTHubClient_LL_SetOption(iotHubClientHandle, OPTION_X509_CERT, x509certificate) != IOTHUB_CLIENT_OK ||
         IoTHubClient_LL_SetOption(iotHubClientHandle, OPTION_X509_PRIVATE_KEY, x509privatekey) != IOTHUB_CLIENT_OK)
     {
-        (void)printf("ERROR: Failed to set options for x509.\n");
+        LogError("Failed to set options for x509.");
         return false;
     }
 
@@ -226,7 +261,7 @@ int main(int argc, char *argv[])
 {
     if (argc < 2)
     {
-        (void)printf("Usage: %s <IoT hub device connection string>\r\n", argv[0]);
+        LogError("Usage: %s <IoT hub device connection string>", argv[0]);
         return 1;
     }
 
@@ -237,7 +272,7 @@ int main(int argc, char *argv[])
 
     if (device_id_src == NULL)
     {
-        (void)printf("ERROR: Cannot parse device id from IoT device connection string\n");
+        LogError("Cannot parse device id from IoT device connection string");
         return 1;
     }
     snprintf(device_id, sizeof(device_id), "%s", device_id_src);
@@ -247,13 +282,13 @@ int main(int argc, char *argv[])
 
     if (platform_init() != 0)
     {
-        (void)printf("Failed to initialize the platform.\r\n");
+        LogError("Failed to initialize the platform.");
     }
     else
     {
         if ((iotHubClientHandle = IoTHubClient_LL_CreateFromConnectionString(argv[1], MQTT_Protocol)) == NULL)
         {
-            (void)printf("ERROR: iotHubClientHandle is NULL!\r\n");
+            LogError("iotHubClientHandle is NULL!");
         }
         else
         {
@@ -269,6 +304,7 @@ int main(int argc, char *argv[])
             // set C2D and device method callback
             IoTHubClient_LL_SetMessageCallback(iotHubClientHandle, receiveMessageCallback, NULL);
             IoTHubClient_LL_SetDeviceMethodCallback(iotHubClientHandle, deviceMethodCallback, NULL);
+            IoTHubClient_LL_SetDeviceTwinCallback(iotHubClientHandle, twinCallback, NULL);
 
             int count = 0;
             while (true)
@@ -286,10 +322,10 @@ int main(int argc, char *argv[])
                         }
                         else
                         {
-                            (void)printf("Failed to read message\r\n");
+                            LogError("Failed to read message");
                         }
                     }
-                    delay(INTERVAL);
+                    delay(interval);
                 }
                 IoTHubClient_LL_DoWork(iotHubClientHandle);
             }