static void prvCreateMQTTConnectionWithBroker()

in source/MutualAuthMQTTExample.c [690:765]

• 45 lines of code
• 1 McCabe index (conditional complexity)

static void prvCreateMQTTConnectionWithBroker( MQTTContext_t * pxMQTTContext,
                                               NetworkContext_t * pxNetworkContext )
{
    MQTTStatus_t xResult;
    MQTTConnectInfo_t xConnectInfo;
    bool xSessionPresent;
    TransportInterface_t xTransport;

    /***
     * For readability, error handling in this function is restricted to the use of
     * asserts().
     ***/

    /* Fill in Transport Interface send and receive function pointers. */
    xTransport.pNetworkContext = pxNetworkContext;
    xTransport.send = TLS_FreeRTOS_send;
    xTransport.recv = TLS_FreeRTOS_recv;

    /* Initialize MQTT library. */
    xResult = MQTT_Init( pxMQTTContext, &xTransport, prvGetTimeMs, prvEventCallback, &xBuffer );
    configASSERT( xResult == MQTTSuccess );

    /* Some fields are not used in this demo so start with everything at 0. */
    ( void ) memset( ( void * ) &xConnectInfo, 0x00, sizeof( xConnectInfo ) );

    /* Start with a clean session i.e. direct the MQTT broker to discard any
     * previous session data. Also, establishing a connection with clean session
     * will ensure that the broker does not store any data when this client
     * gets disconnected. */
    xConnectInfo.cleanSession = true;

    /* The client identifier is used to uniquely identify this MQTT client to
     * the MQTT broker. In a production device the identifier can be something
     * unique, such as a device serial number. */
    xConnectInfo.pClientIdentifier = pThingName;
    xConnectInfo.clientIdentifierLength = ( uint16_t ) strlen( pThingName );

    /* Set MQTT keep-alive period. If the application does not send packets at an interval less than
     * the keep-alive period, the MQTT library will send PINGREQ packets. */
    xConnectInfo.keepAliveSeconds = mqttexampleKEEP_ALIVE_TIMEOUT_SECONDS;

    /* Append metrics when connecting to the AWS IoT Core broker. */
    #ifdef democonfigUSE_AWS_IOT_CORE_BROKER
        #ifdef democonfigCLIENT_USERNAME
            xConnectInfo.pUserName = CLIENT_USERNAME_WITH_METRICS;
            xConnectInfo.userNameLength = ( uint16_t ) strlen( CLIENT_USERNAME_WITH_METRICS );
            xConnectInfo.pPassword = democonfigCLIENT_PASSWORD;
            xConnectInfo.passwordLength = ( uint16_t ) strlen( democonfigCLIENT_PASSWORD );
        #else
            xConnectInfo.pUserName = AWS_IOT_METRICS_STRING;
            xConnectInfo.userNameLength = AWS_IOT_METRICS_STRING_LENGTH;
            /* Password for authentication is not used. */
            xConnectInfo.pPassword = NULL;
            xConnectInfo.passwordLength = 0U;
        #endif
    #else /* ifdef democonfigUSE_AWS_IOT_CORE_BROKER */
        #ifdef democonfigCLIENT_USERNAME
            xConnectInfo.pUserName = democonfigCLIENT_USERNAME;
            xConnectInfo.userNameLength = ( uint16_t ) strlen( democonfigCLIENT_USERNAME );
            xConnectInfo.pPassword = democonfigCLIENT_PASSWORD;
            xConnectInfo.passwordLength = ( uint16_t ) strlen( democonfigCLIENT_PASSWORD );
        #endif /* ifdef democonfigCLIENT_USERNAME */
    #endif /* ifdef democonfigUSE_AWS_IOT_CORE_BROKER */

    /* Send MQTT CONNECT packet to broker. LWT is not used in this demo, so it
     * is passed as NULL. */
    xResult = MQTT_Connect( pxMQTTContext,
                            &xConnectInfo,
                            NULL,
                            mqttexampleCONNACK_RECV_TIMEOUT_MS,
                            &xSessionPresent );
    configASSERT( xResult == MQTTSuccess );

    /* Successfully established and MQTT connection with the broker. */
    LogInfo( ( "An MQTT connection is established with %s.", pEndpoint ) );
}