subscribe_publish_sample.cpp

00001 /*
00002  * Copyright 2010-2015 Amazon.com, Inc. or its affiliates. All Rights Reserved.
00003  *
00004  * Licensed under the Apache License, Version 2.0 (the "License").
00005  * You may not use this file except in compliance with the License.
00006  * A copy of the License is located at
00007  *
00008  *  http://aws.amazon.com/apache2.0
00009  *
00010  * or in the "license" file accompanying this file. This file is distributed
00011  * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
00012  * express or implied. See the License for the specific language governing
00013  * permissions and limitations under the License.
00014  */
00015 
00016 /**
00017  * @file subscribe_publish_sample.c
00018  * @brief simple MQTT publish and subscribe on the same topic
00019  *
00020  * This example takes the parameters from the aws_iot_config.h file and establishes a connection to the AWS IoT MQTT Platform.
00021  * It subscribes and publishes to the same topic - "sdkTest/sub"
00022  *
00023  * If all the certs are correct, you should see the messages received by the application in a loop.
00024  *
00025  * The application takes in the certificate path, host name , port and the number of times the publish should happen.
00026  *
00027  */
00028 #include <stdio.h>
00029 #include <stdlib.h>
00030 #include <ctype.h>
00031 #include <limits.h>
00032 #include <string.h>
00033 
00034 #include "aws_iot_config.h"
00035 #include "aws_iot_log.h"
00036 #include "aws_iot_version.h"
00037 #include "aws_iot_mqtt_client_interface.h"
00038 
00039 #include "easy-connect.h"
00040 #include "WNC14A2AInterface.h"
00041 
00042 #define HOST_ADDRESS_SIZE 255
00043 
00044 Thread aws_subscribe_publish(osPriorityNormal, 16*1024, NULL);
00045 void   aws_subscribe_publish_task(void);
00046 
00047 /**
00048  * @brief Default cert location
00049  */
00050 char certDirectory[PATH_MAX + 1] = "../../../certs";
00051 
00052 /**
00053  * @brief Default MQTT HOST URL is pulled from the aws_iot_config.h
00054  */
00055 char HostAddress[HOST_ADDRESS_SIZE] = AWS_IOT_MQTT_HOST;
00056 
00057 /**
00058  * @brief Default MQTT port is pulled from the aws_iot_config.h
00059  */
00060 uint32_t port = AWS_IOT_MQTT_PORT;
00061 
00062 /**
00063  * @brief This parameter will avoid infinite loop of publish and exit the program after certain number of publishes
00064  */
00065 uint32_t publishCount = 0;
00066 
00067 void iot_subscribe_callback_handler(AWS_IoT_Client *pClient, char *topicName, uint16_t topicNameLen,
00068                                     IoT_Publish_Message_Params *params, void *pData) {
00069     IOT_UNUSED(pData);
00070     IOT_UNUSED(pClient);
00071     IOT_INFO("Subscribe callback");
00072     IOT_INFO("%.*s\t%.*s", topicNameLen, topicName, (int) params->payloadLen, (char *) params->payload);
00073 }
00074 
00075 void disconnectCallbackHandler(AWS_IoT_Client *pClient, void *data) {
00076     IOT_WARN("MQTT Disconnect");
00077     IoT_Error_t rc = FAILURE;
00078 
00079     if(NULL == pClient) {
00080         return;
00081     }
00082 
00083     IOT_UNUSED(data);
00084 
00085     if(aws_iot_is_autoreconnect_enabled(pClient)) {
00086         IOT_INFO("Auto Reconnect is enabled, Reconnecting attempt will start now");
00087     } else {
00088         IOT_WARN("Auto Reconnect not enabled. Starting manual reconnect...");
00089         rc = aws_iot_mqtt_attempt_reconnect(pClient);
00090         if(NETWORK_RECONNECTED == rc) {
00091             IOT_WARN("Manual Reconnect Successful");
00092         } else {
00093             IOT_WARN("Manual Reconnect Failed - %d", rc);
00094         }
00095     }
00096 }
00097 
00098 
00099 int main() 
00100 {
00101     printf("AWS %s Example.\n",__FILE__);
00102     IOT_INFO("\nAWS IoT SDK Version %d.%d.%d-%s\n", VERSION_MAJOR, VERSION_MINOR, VERSION_PATCH, VERSION_TAG);
00103 
00104     aws_subscribe_publish.start(aws_subscribe_publish_task);
00105     aws_subscribe_publish.join();
00106     printf(" - - - - - - - ALL DONE - - - - - - - \n");
00107 }
00108 
00109 void aws_subscribe_publish_task()
00110 {
00111     bool infinitePublishFlag = true;
00112 
00113     char rootCA[PATH_MAX + 1];
00114     char clientCRT[PATH_MAX + 1];
00115     char clientKey[PATH_MAX + 1];
00116     char CurrentWD[PATH_MAX + 1];
00117     char cPayload[100];
00118 
00119     int32_t i = 0;
00120 
00121     IoT_Error_t rc = FAILURE;
00122 
00123     AWS_IoT_Client client;
00124     IoT_Client_Init_Params mqttInitParams = iotClientInitParamsDefault;
00125     IoT_Client_Connect_Params connectParams = iotClientConnectParamsDefault;
00126 
00127     IoT_Publish_Message_Params paramsQOS0;
00128     IoT_Publish_Message_Params paramsQOS1;
00129 
00130     IOT_INFO("\nAWS IoT SDK Version %d.%d.%d-%s\n", VERSION_MAJOR, VERSION_MINOR, VERSION_PATCH, VERSION_TAG);
00131 
00132     snprintf(rootCA, PATH_MAX + 1, "%s/%s/%s", CurrentWD, certDirectory, AWS_IOT_ROOT_CA_FILENAME);
00133     snprintf(clientCRT, PATH_MAX + 1, "%s/%s/%s", CurrentWD, certDirectory, AWS_IOT_CERTIFICATE_FILENAME);
00134     snprintf(clientKey, PATH_MAX + 1, "%s/%s/%s", CurrentWD, certDirectory, AWS_IOT_PRIVATE_KEY_FILENAME);
00135 
00136     IOT_DEBUG("rootCA %s", rootCA);
00137     IOT_DEBUG("clientCRT %s", clientCRT);
00138     IOT_DEBUG("clientKey %s", clientKey);
00139     mqttInitParams.enableAutoReconnect = false; // We enable this later below
00140     mqttInitParams.pHostURL = HostAddress;
00141     mqttInitParams.port = port;
00142     mqttInitParams.pRootCALocation = rootCA;
00143     mqttInitParams.pDeviceCertLocation = clientCRT;
00144     mqttInitParams.pDevicePrivateKeyLocation = clientKey;
00145     mqttInitParams.mqttCommandTimeout_ms = 20000;
00146     mqttInitParams.tlsHandshakeTimeout_ms = 5000;
00147     mqttInitParams.isSSLHostnameVerify = true;
00148     mqttInitParams.disconnectHandler = disconnectCallbackHandler;
00149     mqttInitParams.disconnectHandlerData = NULL;
00150 
00151     rc = aws_iot_mqtt_init(&client, &mqttInitParams);
00152     if(SUCCESS != rc) {
00153         IOT_ERROR("aws_iot_mqtt_init returned error : %d ", rc);
00154         return;
00155     }
00156 
00157     connectParams.keepAliveIntervalInSec = 600;
00158     connectParams.isCleanSession = true;
00159     connectParams.MQTTVersion = MQTT_3_1_1;
00160     connectParams.pClientID = AWS_IOT_MQTT_CLIENT_ID;
00161     connectParams.clientIDLen = (uint16_t) strlen(AWS_IOT_MQTT_CLIENT_ID);
00162     connectParams.isWillMsgPresent = false;
00163 
00164     IOT_INFO("Connecting...");
00165     rc = aws_iot_mqtt_connect(&client, &connectParams);
00166     if(SUCCESS != rc) {
00167         IOT_ERROR("Error(%d) connecting to %s:%d", rc, mqttInitParams.pHostURL, mqttInitParams.port);
00168         return;
00169     }
00170     /*
00171      * Enable Auto Reconnect functionality. Minimum and Maximum time of Exponential backoff are set in aws_iot_config.h
00172      *  #AWS_IOT_MQTT_MIN_RECONNECT_WAIT_INTERVAL
00173      *  #AWS_IOT_MQTT_MAX_RECONNECT_WAIT_INTERVAL
00174      */
00175     rc = aws_iot_mqtt_autoreconnect_set_status(&client, true);
00176     if(SUCCESS != rc) {
00177         IOT_ERROR("Unable to set Auto Reconnect to true - %d", rc);
00178         return;
00179     }
00180 
00181     IOT_INFO("Subscribing...");
00182     rc = aws_iot_mqtt_subscribe(&client, "sdkTest/sub", 11, QOS0, iot_subscribe_callback_handler, NULL);
00183     if(SUCCESS != rc) {
00184         IOT_ERROR("Error subscribing : %d ", rc);
00185         return;
00186     }
00187 
00188     sprintf(cPayload, "%s : %ld ", "hello from SDK", i);
00189 
00190     paramsQOS0.qos = QOS0;
00191     paramsQOS0.payload = (void *) cPayload;
00192     paramsQOS0.isRetained = 0;
00193 
00194     paramsQOS1.qos = QOS1;
00195     paramsQOS1.payload = (void *) cPayload;
00196     paramsQOS1.isRetained = 0;
00197 
00198     if(publishCount != 0) {
00199         infinitePublishFlag = false;
00200     }
00201 
00202     while((NETWORK_ATTEMPTING_RECONNECT == rc || NETWORK_RECONNECTED == rc || SUCCESS == rc)
00203           && (publishCount > 0 || infinitePublishFlag)) {
00204 
00205         //Max time the yield function will wait for read messages
00206         rc = aws_iot_mqtt_yield(&client, 100);
00207         if(NETWORK_ATTEMPTING_RECONNECT == rc) {
00208             // If the client is attempting to reconnect we will skip the rest of the loop.
00209             continue;
00210         }
00211 
00212         IOT_INFO("-->sleep");
00213         wait(1);
00214         sprintf(cPayload, "%s : %ld ", "hello from SDK QOS0", i++);
00215         paramsQOS0.payloadLen = strlen(cPayload);
00216         rc = aws_iot_mqtt_publish(&client, "sdkTest/sub", 11, &paramsQOS0);
00217         if(publishCount > 0) {
00218             publishCount--;
00219         }
00220 
00221         if(publishCount == 0 && !infinitePublishFlag) {
00222             break;
00223         }
00224 
00225         sprintf(cPayload, "%s : %ld ", "hello from SDK QOS1", i++);
00226         paramsQOS1.payloadLen = strlen(cPayload);
00227         rc = aws_iot_mqtt_publish(&client, "sdkTest/sub", 11, &paramsQOS1);
00228         if (rc == MQTT_REQUEST_TIMEOUT_ERROR) {
00229             IOT_WARN("QOS1 publish ack not received.\n");
00230             rc = SUCCESS;
00231         }
00232         if(publishCount > 0) {
00233             publishCount--;
00234         }
00235     }
00236 
00237     // Wait for all the messages to be received
00238     aws_iot_mqtt_yield(&client, 100);
00239 
00240     if(SUCCESS != rc) {
00241         IOT_ERROR("An error occurred in the loop.\n");
00242     } else {
00243         IOT_INFO("Publish done\n");
00244     }
00245 
00246     return;
00247 }
00248 
00249