lsst.ctrl.events::EventTransmitter Class Reference

Transmit events to the event bus. More...

#include <EventTransmitter.h>

Public Member Functions
	EventTransmitter (const std::string &hostName, const std::string &topicName, int hostPort=EventBroker::DEFAULTHOSTPORT)
	Transmits events to the specified host and topic. More...
	~EventTransmitter ()
	destructor More...
std::string	getTopicName ()
	get the topic name of this EventTransmitter More...
void	publishEvent (Event &event)
	Publish an Event to this object's topic. More...

Private Member Functions
void	init (const std::string &hostName, const std::string &topicName, int port)

Private Attributes
cms::Connection *	_connection
cms::Session *	_session
cms::Destination *	_destination
cms::MessageProducer *	_producer
std::string	_brokerUri
activemq::commands::ActiveMQTopic *	_topic
std::string	_topicName

Detailed Description

Transmit events to the event bus.

Definition at line 60 of file EventTransmitter.h.

Constructor & Destructor Documentation

lsst.ctrl.events::EventTransmitter::EventTransmitter	(	const std::string &	hostName,
		const std::string &	topicName,
		int	hostPort = EventBroker::DEFAULTHOSTPORT
	)

Transmits events to the specified host and topic.

Parameters

hostName	the machine hosting the message broker
topicName	the topic to transmit events to
hostPort	the port number which the message broker is listening to

Exceptions

RuntimeError	if local socket can't be created
RuntimeError	if connect to local socket fails
RuntimeError	if connect to remote ActiveMQ host fails

Definition at line 64 of file EventTransmitter.cc.

                                                                                                       {
    EventLibrary().initializeLibrary();

    init(hostName, topicName, hostPort);
}

lsst.ctrl.events::EventTransmitter::~EventTransmitter

(

)

destructor

Definition at line 147 of file EventTransmitter.cc.

                                    {

    if (_topic != NULL)
        delete _topic;
    _topic = NULL;

    try {
        if( _producer != NULL )
            delete _producer;
    } catch ( cms::CMSException& e ) {
        e.printStackTrace();
    }
    _producer = NULL;

    // Close open resources.
    try {
        if( _session != NULL )
            _session->close();
        if( _connection != NULL )
            _connection->close();
    } catch ( cms::CMSException& e ) {
        e.printStackTrace();
    }

    try {
        if( _session != NULL )
            delete _session;
    } catch ( cms::CMSException& e ) {
        e.printStackTrace();
    }
    _session = NULL;

    try {
        if( _connection != NULL )
            delete _connection;
    } catch ( cms::CMSException& e ) {
        e.printStackTrace();
    }
    _connection = NULL;
}

Member Function Documentation

std::string lsst.ctrl.events::EventTransmitter::getTopicName

(

)

get the topic name of this EventTransmitter

Returns

a std::string containing the topic name

Definition at line 143 of file EventTransmitter.cc.

                                         {
    return _topicName;
}

void lsst.ctrl.events::EventTransmitter::init ( const std::string &  hostName, const std::string &  topicName, int  port  )

private

Definition at line 73 of file EventTransmitter.cc.

                                                                                                {
    _connection = NULL;
    _session = NULL;
    
    _producer = NULL;
    _topicName = topicName;
    _topic = NULL;

    // set up a connection to the ActiveMQ server for message transmission
    try {
        std::stringstream ss;

        ss << hostPort;

        /*
         * Create a ConnectionFactory to connect to hostName, and
         * create a topic for this.
         */
        string brokerUri = "tcp://"+hostName+":"+ss.str()+"?wireFormat=openwire&transport.useAsyncSend=true";

        activemq::core::ActiveMQConnectionFactory* connectionFactory =
            new activemq::core::ActiveMQConnectionFactory( brokerUri );

        _connection = 0;
        try {
            _connection = connectionFactory->createConnection();
            _connection->start();
            delete connectionFactory;
        }
        catch (cms::CMSException& e) {
            delete connectionFactory;
            std::string msg("Failed to connect to broker: ");
            msg += e.getMessage();
            msg += " (is broker running?)";
            throw LSST_EXCEPT(pexExceptions::RuntimeError, msg);
        }

        _session = _connection->createSession( cms::Session::AUTO_ACKNOWLEDGE );
       
        // Create the destination topic
        //_destination = _session->createTopic( topicName );

        // Create Topic
        _topic = new activemq::commands::ActiveMQTopic(_topicName);
        

        // Create a MessageProducer from the Session to the Topic or Queue
        _producer = _session->createProducer(NULL);
        _producer->setDeliveryMode( cms::DeliveryMode::NON_PERSISTENT );
    } catch ( cms::CMSException& e ) {
        throw LSST_EXCEPT(pexExceptions::RuntimeError, std::string("Trouble creating EventTransmitter: ") + e.getMessage());
    }
}

void lsst.ctrl.events::EventTransmitter::publishEvent

(

Event &

event

)

Publish an Event to this object's topic.

Parameters

event

an Event to publish

Definition at line 127 of file EventTransmitter.cc.

                                                {
    long long pubtime;
    cms::TextMessage* message = _session->createTextMessage();

    event.marshall(message);

    message->setStringProperty("TOPIC", _topicName);

    // wait until the last moment to timestamp publication time
    pubtime = dafBase::DateTime::now().nsecs();
    message->setLongProperty("PUBTIME", pubtime);

    _producer->send(_topic, message);
    delete message;
}

Member Data Documentation

std::string lsst.ctrl.events::EventTransmitter::_brokerUri

private

Definition at line 108 of file EventTransmitter.h.

cms::Connection* lsst.ctrl.events::EventTransmitter::_connection

private

Definition at line 96 of file EventTransmitter.h.

cms::Destination* lsst.ctrl.events::EventTransmitter::_destination

private

Definition at line 102 of file EventTransmitter.h.

cms::MessageProducer* lsst.ctrl.events::EventTransmitter::_producer

private

Definition at line 105 of file EventTransmitter.h.

cms::Session* lsst.ctrl.events::EventTransmitter::_session

private

Definition at line 99 of file EventTransmitter.h.

activemq::commands::ActiveMQTopic* lsst.ctrl.events::EventTransmitter::_topic

private

Definition at line 110 of file EventTransmitter.h.

std::string lsst.ctrl.events::EventTransmitter::_topicName

private

Definition at line 111 of file EventTransmitter.h.

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The documentation for this class was generated from the following files:

• /home/lsstsw/stack/Linux64/ctrl_events/10.0-6-g462a451+1/include/lsst/ctrl/events/EventTransmitter.h
• /home/lsstsw/stack/Linux64/ctrl_events/10.0-6-g462a451+1/src/EventTransmitter.cc