zeroeq::Publisher Class Reference

Serves and publishes events, consumed by Subscriber. More...

#include <publisher.h>

Inheritance diagram for zeroeq::Publisher:

Collaboration diagram for zeroeq::Publisher:

Public Member Functions
	Publisher ()
	Create a default publisher. More...
	Publisher (const std::string &session)
	Create a publisher which announces the specified session. More...
	Publisher (const URI &uri)
	Create a publisher which runs on the specified URI. More...
	Publisher (const URI &uri, const std::string &session)
	Create a publisher which runs on the specified URI and announces the specified session. More...
bool	publish (const servus::Serializable &serializable)
	Publish the given serializable object to any subscriber. More...
bool	publish (const uint128_t &event)
	Publish the given event to any subscriber. More...
bool	publish (const uint128_t &event, const void *data, size_t size)
	Publish the given event with payload to any subscriber. More...
const URI &	getURI () const
	Get the publisher URI. More...
const std::string &	getSession () const
std::string	getAddress () const

Detailed Description

Serves and publishes events, consumed by Subscriber.

The session is tied to ZeroConf announcement and can be disabled by passing zeroeq::NULL_SESSION as the session name.

Example:

/* Copyright (c) 2015-2017, Human Brain Project
 *                          Daniel Nachbaur <daniel.nachbaur@epfl.ch>
 *                          Stefan.Eilemann@epfl.ch
 *                          Juan Hernando <jhernando@fi.upm.es>
 */

#define BOOST_TEST_MODULE zeroeq_publisher

#include "common.h"
#include <zeroeq/detail/common.h>
#include <zeroeq/detail/constants.h>
#include <zeroeq/detail/sender.h>

#include <servus/servus.h>

BOOST_AUTO_TEST_CASE(create_uri_publisher)
{
    const zeroeq::Publisher publisher(zeroeq::URI(""));

    const zeroeq::URI& uri = publisher.getURI();
    const std::string expectedScheme("tcp");
    const std::string baseScheme =
        uri.getScheme().substr(0, expectedScheme.length());
    BOOST_CHECK_EQUAL(baseScheme, expectedScheme);
    BOOST_CHECK(!uri.getHost().empty());
    BOOST_CHECK(uri.getPort() > 1024);
}

BOOST_AUTO_TEST_CASE(create_invalid_uri_publisher)
{
    // invalid URI, hostname only not allowed
    BOOST_CHECK_THROW(zeroeq::Publisher publisher(zeroeq::URI("localhost")),
                      std::runtime_error);
}

BOOST_AUTO_TEST_CASE(publish)
{
    zeroeq::Publisher publisher(zeroeq::NULL_SESSION);
    test::Echo echo(test::echoMessage);
    BOOST_CHECK(publisher.publish(echo));
    BOOST_CHECK(publisher.publish(echo.getTypeIdentifier(),
                                  echo.toBinary().ptr.get(),
                                  echo.toBinary().size));
}

BOOST_AUTO_TEST_CASE(publish_update_uri)
{
    zeroeq::Publisher publisher(zeroeq::NULL_SESSION);
    const zeroeq::URI& uri = publisher.getURI();
    BOOST_CHECK_MESSAGE(uri.getPort() != 0, uri);
    BOOST_CHECK_MESSAGE(!uri.getHost().empty(), uri);
    BOOST_CHECK(publisher.publish(test::Echo(test::echoMessage)));
}

BOOST_AUTO_TEST_CASE(publish_empty_event)
{
    zeroeq::Publisher publisher(zeroeq::NULL_SESSION);
    BOOST_CHECK(publisher.publish(test::Empty()));
    BOOST_CHECK(publisher.publish(zeroeq::make_uint128("Empty")));
}

BOOST_AUTO_TEST_CASE(multiple_publisher_on_same_host)
{
    if (!servus::Servus::isAvailable() || getenv("TRAVIS"))
        return;

    const zeroeq::Publisher publisher1;
    const zeroeq::Publisher publisher2;
    const zeroeq::Publisher publisher3;

    servus::Servus service(PUBLISHER_SERVICE);
    const servus::Strings& instances =
        service.discover(servus::Servus::IF_LOCAL, 1000);
    BOOST_CHECK_EQUAL(instances.size(), 3);
}

BOOST_AUTO_TEST_CASE(zeroconf_record)
{
    if (!servus::Servus::isAvailable() || getenv("TRAVIS"))
        return;

    const zeroeq::Publisher publisher;

    servus::Servus service(PUBLISHER_SERVICE);
    const servus::Strings& instances =
        service.discover(servus::Servus::IF_LOCAL, 1000);
    BOOST_REQUIRE_EQUAL(instances.size(), 1);

    const std::string& instance = instances[0];
    BOOST_CHECK_EQUAL(instance, publisher.getAddress());
    BOOST_CHECK_EQUAL(service.get(instance, KEY_APPLICATION), "publisher");
    BOOST_CHECK_EQUAL(zeroeq::uint128_t(service.get(instance, KEY_INSTANCE)),
                      zeroeq::detail::Sender::getUUID());
    BOOST_CHECK_EQUAL(service.get(instance, KEY_SESSION), getUserName());
    BOOST_CHECK_EQUAL(service.get(instance, KEY_USER), getUserName());
}

BOOST_AUTO_TEST_CASE(custom_session)
{
    const zeroeq::Publisher publisher(zeroeq::TEST_SESSION);

    servus::Servus service(zeroeq::TEST_SESSION);
    const servus::Strings& instances =
        service.discover(servus::Servus::IF_LOCAL, 1000);
    BOOST_REQUIRE_EQUAL(instances.size(), 1);

    const std::string& instance = instances[0];
    BOOST_CHECK_EQUAL(service.get(instance, KEY_SESSION),
                      publisher.getSession());
}

BOOST_AUTO_TEST_CASE(different_session_at_runtime)
{
    if (!servus::Servus::isAvailable() || getenv("TRAVIS"))
        return;

    setenv("ZEROEQ_PUB_SESSION", "testsession", 1);
    const zeroeq::Publisher publisher;

    servus::Servus service(PUBLISHER_SERVICE);
    const servus::Strings& instances =
        service.discover(servus::Servus::IF_LOCAL, 1000);
    BOOST_REQUIRE_EQUAL(instances.size(), 1);

    const std::string& instance = instances[0];
    BOOST_CHECK_EQUAL(service.get(instance, KEY_SESSION), "testsession");
    unsetenv("ZEROEQ_PUB_SESSION");
}

BOOST_AUTO_TEST_CASE(empty_session)
{
    BOOST_CHECK_THROW(const zeroeq::Publisher publisher(""),
                      std::runtime_error);
}

BOOST_AUTO_TEST_CASE(empty_session_from_environment)
{
    setenv("ZEROEQ_PUB_SESSION", "", 1);

    const zeroeq::Publisher publisher;
    BOOST_CHECK_EQUAL(publisher.getSession(), getUserName());

    unsetenv("ZEROEQ_PUB_SESSION");
}

BOOST_AUTO_TEST_CASE(fixed_uri_and_session)
{
    const zeroeq::Publisher publisher(zeroeq::URI("127.0.0.1"),
                                      zeroeq::TEST_SESSION);
    servus::Servus service(zeroeq::TEST_SESSION);
    const servus::Strings& instances =
        service.discover(servus::Servus::IF_LOCAL, 1000);
    BOOST_REQUIRE_EQUAL(instances.size(), 1);
}

Definition at line 26 of file publisher.h.

Constructor & Destructor Documentation

zeroeq::Publisher::Publisher

(

)

Create a default publisher.

Postconditions:

• bound to all network interfaces
• runs on a random port
• announces itself on the _zeroeq_pub._tcp ZeroConf service as host:port
• announces session <username> or ZEROEQ_PUB_SESSION from environment

Exceptions

std::runtime_error

if session is empty or socket setup fails

zeroeq::Publisher::Publisher ( const std::string &  session )

explicit

Create a publisher which announces the specified session.

Postconditions:

• bound to all network interfaces
• runs on a random port
• announces itself on the _zeroeq_pub._tcp ZeroConf service as host:port
• announces given session

Parameters

session

session name used for announcement

Exceptions

std::runtime_error

if session is empty or socket setup fails

zeroeq::Publisher::Publisher ( const URI &  uri )

explicit

Create a publisher which runs on the specified URI.

Postconditions:

• bound to the host and/or port from the given URI
• announces itself on the _zeroeq_pub._tcp ZeroConf service as host:port
• announces session <username> or ZEROEQ_PUB_SESSION from environment

Parameters

uri	publishing URI in the format [scheme://][*|host|IP|IF][:port]

Exceptions

std::runtime_error

if session is empty or socket setup fails

zeroeq::Publisher::Publisher	(	const URI &	uri,
		const std::string &	session
	)

Create a publisher which runs on the specified URI and announces the specified session.

Postconditions:

• bound to the host and/or port from the given URI
• announces itself on the _zeroeq_pub._tcp ZeroConf service as host:port
• announces given session

Parameters

session	session name used for announcement
uri	publishing URI in the format [scheme://][*|host|IP|IF][:port]

Exceptions

std::runtime_error

if session is empty or socket setup fails

Member Function Documentation

const std::string& zeroeq::Publisher::getSession

(

)

const

Returns

the session name that is announced

const URI& zeroeq::Publisher::getURI

(

)

const

Get the publisher URI.

Contains the used hostname and port, if none where given in the constructor uri.

Returns

the publisher URI.

bool zeroeq::Publisher::publish

(

const servus::Serializable &

serializable

)

Publish the given serializable object to any subscriber.

If there is no subscriber for that serializable, no message will be sent.

Parameters

serializable

the object to publish

Returns

true if publish was successful

bool zeroeq::Publisher::publish

(

const uint128_t &

event

)

Publish the given event to any subscriber.

If there is no subscriber for that event, no message will be sent.

Parameters

event

the event identifier to publish

Returns

true if publish was successful

bool zeroeq::Publisher::publish	(	const uint128_t &	event,
		const void *	data,
		size_t	size
	)

Publish the given event with payload to any subscriber.

If there is no subscriber for that event, no message will be sent.

Parameters

event	the event identifier to publish
data	the payload data of the event
size	the size of the payload data

Returns

true if publish was successful

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

• publisher.h