lsst::ctrl::events::EventSystem Class Reference

This object allows creation of the system's event transmitters and receivers, which can be specified at the beginning, and later used by specifying the topic to receive from or send on. More...

#include <EventSystem.h>

Public Member Functions
	~EventSystem ()
	destructor More...
void	createTransmitter (std::string const &hostName, std::string const &topicName, int hostPort=EventBroker::DEFAULTHOSTPORT)
	create an EventTransmitter to send messages to the message broker More...
void	createReceiver (std::string const &hostName, std::string const &topicName, int hostPort=EventBroker::DEFAULTHOSTPORT)
	create an EventReceiver which will receive message More...
void	createReceiver (std::string const &hostName, std::string const &topicName, std::string const &selector, int hostPort=EventBroker::DEFAULTHOSTPORT)
	create an EventReceiver which will receive message More...
void	publishEvent (std::string const &topicName, Event &event)
	send an event on a topic More...
Event *	receiveEvent (std::string const &topicName)
	blocking receive for events. Waits until an event is received for the topic specified in the constructor More...
Event *	receiveEvent (std::string const &topicName, const long timeout)
	blocking receive for events, with timeout (in milliseconds). Waits until an event is received for the topic specified in the constructor, or until the timeout expires. More...
LocationId::Ptr	createOriginatorId () const
	create an LocationId More...
StatusEvent *	castToStatusEvent (Event *event)
	cast an Event to StatusEvent More...
CommandEvent *	castToCommandEvent (Event *event)
	cast an Event to CommandEvent More...

Static Public Member Functions
static EventSystem &	getDefaultEventSystem ()
	return the default EventSystem object, which can access all previously created Transmitters and receivers More...

Protected Member Functions
	EventSystem ()

Static Protected Attributes
static list< boost::shared_ptr < EventTransmitter > >	_transmitters
static list< boost::shared_ptr < EventReceiver > >	_receivers

Private Member Functions
boost::shared_ptr < EventTransmitter >	getTransmitter (std::string const &name)
boost::shared_ptr< EventReceiver >	getReceiver (std::string const &name)

Static Private Attributes
static EventSystem *	defaultEventSystem = 0

Detailed Description

This object allows creation of the system's event transmitters and receivers, which can be specified at the beginning, and later used by specifying the topic to receive from or send on.

Definition at line 65 of file EventSystem.h.

Constructor & Destructor Documentation

lsst::ctrl::events::EventSystem::~EventSystem

(

)

destructor

Definition at line 66 of file EventSystem.cc.

                          {
}

lsst::ctrl::events::EventSystem::EventSystem ( )

protected

Definition at line 62 of file EventSystem.cc.

                         {
    EventLibrary().initializeLibrary();
}

Member Function Documentation

CommandEvent * lsst::ctrl::events::EventSystem::castToCommandEvent

(

Event *

event

)

cast an Event to CommandEvent

Parameters

event

an Event

Returns

a CommandEvent

Definition at line 159 of file EventSystem.cc.

                                                          {
    return (CommandEvent *)event;
}

StatusEvent * lsst::ctrl::events::EventSystem::castToStatusEvent

(

Event *

event

)

cast an Event to StatusEvent

Parameters

event

an Event

Returns

a StatusEvent

Definition at line 155 of file EventSystem.cc.

                                                        {
    return (StatusEvent *)event;
}

LocationId::Ptr lsst::ctrl::events::EventSystem::createOriginatorId

(

)

const

create an LocationId

Returns

LocationId::Ptr

Definition at line 139 of file EventSystem.cc.

                                                    {
    return LocationId::Ptr(new LocationId());
}

void lsst::ctrl::events::EventSystem::createReceiver	(	std::string const &	hostName,
		std::string const &	topicName,
		int	hostPort = EventBroker::DEFAULTHOSTPORT
	)

create an EventReceiver which will receive message

Parameters

hostName	the location of the message broker to use
topicName	the topic to receive messages from
hostPort	the port where the broker can be reached

Exceptions

lsst::pex::exceptions::RuntimeError

if topic is already registered

Definition at line 89 of file EventSystem.cc.

                                                                                                    {
    boost::shared_ptr<EventReceiver> receiver;
    if ((receiver = getReceiver(topicName)) == 0) {
        boost::shared_ptr<EventReceiver> receiver(new EventReceiver(hostName, topicName, hostPort));
        _receivers.push_back(receiver);
        return;
    }
    throw LSST_EXCEPT(pexExceptions::RuntimeError, "topic "+ topicName + " is already registered with EventSystem");
}

void lsst::ctrl::events::EventSystem::createReceiver	(	std::string const &	hostName,
		std::string const &	topicName,
		std::string const &	selector,
		int	hostPort = EventBroker::DEFAULTHOSTPORT
	)

create an EventReceiver which will receive message

Parameters

hostName	the location of the message broker to use
topicName	the topic to receive messages from
selector	the message selector to specify which messages to receive
hostPort	the port where the broker can be reached

Definition at line 99 of file EventSystem.cc.

                                                                                                                               {
    boost::shared_ptr<EventReceiver> receiver(new EventReceiver(hostName, topicName, selector, hostPort));
    _receivers.push_back(receiver);
}

void lsst::ctrl::events::EventSystem::createTransmitter	(	std::string const &	hostName,
		std::string const &	topicName,
		int	hostPort = EventBroker::DEFAULTHOSTPORT
	)

create an EventTransmitter to send messages to the message broker

Parameters

hostName	the location of the message broker to use
topicName	the topic to transmit events to
hostPort	the port where the broker can be reached

Exceptions

lsst::pex::exceptions::RuntimeError

if topic is already registered

Definition at line 79 of file EventSystem.cc.

                                                                                                       {
    boost::shared_ptr<EventTransmitter> transmitter;
    if ((transmitter = getTransmitter(topicName)) == 0) {
        boost::shared_ptr<EventTransmitter> transmitter(new EventTransmitter(hostName, topicName, hostPort));
        _transmitters.push_back(transmitter);
        return;
    }
    throw LSST_EXCEPT(pexExceptions::RuntimeError, "topic "+ topicName + " is already registered with EventSystem");
}

EventSystem & lsst::ctrl::events::EventSystem::getDefaultEventSystem ( )

static

return the default EventSystem object, which can access all previously created Transmitters and receivers

Returns

The EventSystem object

Definition at line 69 of file EventSystem.cc.

                                                {
    static EventSystem eventSystem;
    return eventSystem;

}

boost::shared_ptr< EventReceiver > lsst::ctrl::events::EventSystem::getReceiver ( std::string const &  name )

private

private method used to retrieve the named EventReceiver object

Definition at line 145 of file EventSystem.cc.

                                                                             {
    list<boost::shared_ptr<EventReceiver> >::iterator i;
    for (i = _receivers.begin(); i != _receivers.end(); i++) {
        if ((*i)->getTopicName() == name)
            return *i;
    }
    return boost::shared_ptr<EventReceiver>();
}

boost::shared_ptr< EventTransmitter > lsst::ctrl::events::EventSystem::getTransmitter ( std::string const &  name )

private

private method to retrieve a transmitter from the internal list

Definition at line 115 of file EventSystem.cc.

                                                                                   {
    list<boost::shared_ptr<EventTransmitter> >::iterator i;
    for (i = _transmitters.begin(); i != _transmitters.end(); i++) {
        if ((*i)->getTopicName() == name) {
            return *i;
        }
    }
    return boost::shared_ptr<EventTransmitter>();
}

void lsst::ctrl::events::EventSystem::publishEvent	(	std::string const &	topicName,
		Event &	event
	)

send an event on a topic

Parameters

topicName	the topic to send messages to
event	the Event to send

Exceptions

Runtime

exception if the topic wasn't already registered using the createTransmitter method

Definition at line 105 of file EventSystem.cc.

                                                                       {
    boost::shared_ptr<EventTransmitter> transmitter;
    if ((transmitter = getTransmitter(topicName)) == 0) {
        throw LSST_EXCEPT(pexExceptions::RuntimeError, "topic "+ topicName + " is not registered with EventSystem");
    }
    transmitter->publishEvent(event);
}

Event * lsst::ctrl::events::EventSystem::receiveEvent

(

std::string const &

topicName

)

blocking receive for events. Waits until an event is received for the topic specified in the constructor

Parameters

topicName

the topic to listen on

Returns

a PropertySet::Ptr object

Definition at line 126 of file EventSystem.cc.

                                                           {
    return receiveEvent(topicName, EventReceiver::infiniteTimeout);
}

Event * lsst::ctrl::events::EventSystem::receiveEvent	(	std::string const &	topicName,
		const long	timeout
	)

blocking receive for events, with timeout (in milliseconds). Waits until an event is received for the topic specified in the constructor, or until the timeout expires.

Parameters

topicName	the topic to listen on
timeout	the time in milliseconds to wait before returning

Returns

a Property::Ptr object on success, 0 on failure

Definition at line 130 of file EventSystem.cc.

                                                                               {
    boost::shared_ptr<EventReceiver> receiver;
    if ((receiver = getReceiver(topicName)) == 0) {
        throw LSST_EXCEPT(pexExceptions::RuntimeError, "Topic "+ topicName +" is not registered with EventSystem");
    }

    return receiver->receiveEvent(timeout);
}

Member Data Documentation

list< boost::shared_ptr< EventReceiver > > lsst::ctrl::events::EventSystem::_receivers

staticprotected

Definition at line 165 of file EventSystem.h.

list< boost::shared_ptr< EventTransmitter > > lsst::ctrl::events::EventSystem::_transmitters

staticprotected

Definition at line 164 of file EventSystem.h.

EventSystem * lsst::ctrl::events::EventSystem::defaultEventSystem = 0

staticprivate

Definition at line 155 of file EventSystem.h.

---

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

• /home/lsstsw/stack/Linux64/ctrl_events/11.0.rc2+8/include/lsst/ctrl/events/EventSystem.h
• /home/lsstsw/stack/Linux64/ctrl_events/11.0.rc2+8/src/EventSystem.cc