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A simple IoTHub sample using MQTT as transport
Dependencies: EthernetInterface NTPClient mbed-rtos mbed wolfSSL azure_c_shared_utility iothub_client azure_umqtt_c iothub_mqtt_transport serializer
Diff: simplesample_mqtt.c
- Revision:
- 2:eef448cf9eb7
- Child:
- 4:79b01589ddcb
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/simplesample_mqtt.c Fri Mar 25 16:10:49 2016 -0700 @@ -0,0 +1,215 @@ +// Copyright (c) Microsoft. All rights reserved. +// Licensed under the MIT license. See LICENSE file in the project root for full license information. + +#include <stdlib.h> + +#include <stdio.h> +#include <stdint.h> + +/* This sample uses the _LL APIs of iothub_client for example purposes. +That does not mean that MQTT only works with the _LL APIs. +Simply changing the using the convenience layer (functions not having _LL) +and removing calls to _DoWork will yield the same results. */ + +#include "serializer.h" +#include "iothub_client_ll.h" +#include "iothubtransportmqtt.h" +#include "threadapi.h" +#include "platform.h" + +/*String containing Hostname, Device Id & Device Key in the format: */ +/* "HostName=<host_name>;DeviceId=<device_id>;SharedAccessKey=<device_key>" */ +static const char* connectionString = "[device connection string]"; + +// Define the Model +BEGIN_NAMESPACE(WeatherStation); + +DECLARE_MODEL(ContosoAnemometer, +WITH_DATA(ascii_char_ptr, DeviceId), +WITH_DATA(int, WindSpeed), +WITH_ACTION(TurnFanOn), +WITH_ACTION(TurnFanOff), +WITH_ACTION(SetAirResistance, int, Position) +); + +END_NAMESPACE(WeatherStation); + +DEFINE_ENUM_STRINGS(IOTHUB_CLIENT_CONFIRMATION_RESULT, IOTHUB_CLIENT_CONFIRMATION_RESULT_VALUES) + +EXECUTE_COMMAND_RESULT TurnFanOn(ContosoAnemometer* device) +{ + (void)device; + (void)printf("Turning fan on.\r\n"); + return EXECUTE_COMMAND_SUCCESS; +} + +EXECUTE_COMMAND_RESULT TurnFanOff(ContosoAnemometer* device) +{ + (void)device; + (void)printf("Turning fan off.\r\n"); + return EXECUTE_COMMAND_SUCCESS; +} + +EXECUTE_COMMAND_RESULT SetAirResistance(ContosoAnemometer* device, int Position) +{ + (void)device; + (void)printf("Setting Air Resistance Position to %d.\r\n", Position); + return EXECUTE_COMMAND_SUCCESS; +} + +void sendCallback(IOTHUB_CLIENT_CONFIRMATION_RESULT result, void* userContextCallback) +{ + int messageTrackingId = (intptr_t)userContextCallback; + + (void)printf("Message Id: %d Received.\r\n", messageTrackingId); + + (void)printf("Result Call Back Called! Result is: %s \r\n", ENUM_TO_STRING(IOTHUB_CLIENT_CONFIRMATION_RESULT, result)); +} + +static void sendMessage(IOTHUB_CLIENT_LL_HANDLE iotHubClientHandle, const unsigned char* buffer, size_t size) +{ + static unsigned int messageTrackingId; + IOTHUB_MESSAGE_HANDLE messageHandle = IoTHubMessage_CreateFromByteArray(buffer, size); + if (messageHandle == NULL) + { + printf("unable to create a new IoTHubMessage\r\n"); + } + else + { + if (IoTHubClient_LL_SendEventAsync(iotHubClientHandle, messageHandle, sendCallback, (void*)(uintptr_t)messageTrackingId) != IOTHUB_CLIENT_OK) + { + printf("failed to hand over the message to IoTHubClient"); + } + else + { + printf("IoTHubClient accepted the message for delivery\r\n"); + } + IoTHubMessage_Destroy(messageHandle); + } + free((void*)buffer); + messageTrackingId++; +} + +/*this function "links" IoTHub to the serialization library*/ +static IOTHUBMESSAGE_DISPOSITION_RESULT IoTHubMessage(IOTHUB_MESSAGE_HANDLE message, void* userContextCallback) +{ + IOTHUBMESSAGE_DISPOSITION_RESULT result; + const unsigned char* buffer; + size_t size; + if (IoTHubMessage_GetByteArray(message, &buffer, &size) != IOTHUB_MESSAGE_OK) + { + printf("unable to IoTHubMessage_GetByteArray\r\n"); + result = EXECUTE_COMMAND_ERROR; + } + else + { + /*buffer is not zero terminated*/ + char* temp = malloc(size + 1); + if (temp == NULL) + { + printf("failed to malloc\r\n"); + result = EXECUTE_COMMAND_ERROR; + } + else + { + memcpy(temp, buffer, size); + temp[size] = '\0'; + EXECUTE_COMMAND_RESULT executeCommandResult = EXECUTE_COMMAND(userContextCallback, temp); + result = + (executeCommandResult == EXECUTE_COMMAND_ERROR) ? IOTHUBMESSAGE_ABANDONED : + (executeCommandResult == EXECUTE_COMMAND_SUCCESS) ? IOTHUBMESSAGE_ACCEPTED : + IOTHUBMESSAGE_REJECTED; + free(temp); + } + } + return result; +} + +void simplesample_mqtt_run(void) +{ + if (platform_init() != 0) + { + (void)printf("Failed to initialize platform.\r\n"); + } + else + { + if (serializer_init(NULL) != SERIALIZER_OK) + { + (void)printf("Failed on serializer_init\r\n"); + } + else + { + IOTHUB_CLIENT_LL_HANDLE iotHubClientHandle = IoTHubClient_LL_CreateFromConnectionString(connectionString, MQTT_Protocol); + srand((unsigned int)time(NULL)); + int avgWindSpeed = 10; + + if (iotHubClientHandle == NULL) + { + (void)printf("Failed on IoTHubClient_LL_Create\r\n"); + } + else + { + + ContosoAnemometer* myWeather = CREATE_MODEL_INSTANCE(WeatherStation, ContosoAnemometer); + if (myWeather == NULL) + { + (void)printf("Failed on CREATE_MODEL_INSTANCE\r\n"); + } + else + { + if (IoTHubClient_LL_SetMessageCallback(iotHubClientHandle, IoTHubMessage, myWeather) != IOTHUB_CLIENT_OK) + { + printf("unable to IoTHubClient_SetMessageCallback\r\n"); + } + else + { + myWeather->DeviceId = "myFirstDevice"; + myWeather->WindSpeed = avgWindSpeed + (rand() % 4 + 2); + { + unsigned char* destination; + size_t destinationSize; + if (SERIALIZE(&destination, &destinationSize, myWeather->DeviceId, myWeather->WindSpeed) != IOT_AGENT_OK) + { + (void)printf("Failed to serialize\r\n"); + } + else + { + IOTHUB_MESSAGE_HANDLE messageHandle = IoTHubMessage_CreateFromByteArray(destination, destinationSize); + if (messageHandle == NULL) + { + printf("unable to create a new IoTHubMessage\r\n"); + } + else + { + if (IoTHubClient_LL_SendEventAsync(iotHubClientHandle, messageHandle, sendCallback, (void*)1) != IOTHUB_CLIENT_OK) + { + printf("failed to hand over the message to IoTHubClient"); + } + else + { + printf("IoTHubClient accepted the message for delivery\r\n"); + } + + IoTHubMessage_Destroy(messageHandle); + } + free(destination); + } + } + + /* wait for commands */ + while (1) + { + IoTHubClient_LL_DoWork(iotHubClientHandle); + ThreadAPI_Sleep(100); + } + } + + DESTROY_MODEL_INSTANCE(myWeather); + } + IoTHubClient_LL_Destroy(iotHubClientHandle); + } + serializer_deinit(); + } + platform_deinit(); + } +}