Publish consumed data on a ROS topic. More...

#include <fkie_message_filters/publisher.hpp>

Inheritance diagram for fkie_message_filters::Publisher< M, Translate >:

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Collaboration diagram for fkie_message_filters::Publisher< M, Translate >:

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Public Types
using	Input = IO< Inputs... >
	Grouped input types.

Public Member Functions
	Publisher () noexcept
	Constructs an empty publisher.

	Publisher (rclcpp::Node::SharedPtr &node, const std::string &topic, const rclcpp::QoS &qos=rclcpp::QoS(rclcpp::KeepLast(10), rmw_qos_profile_default), const rclcpp::PublisherOptions &options=rclcpp::PublisherOptions()) noexcept
	Constructor that advertises the given ROS topic.

virtual	~Publisher ()
	Destructor.

void	advertise (rclcpp::Node::SharedPtr &node, const std::string &topic, const rclcpp::QoS &qos=rclcpp::QoS(rclcpp::KeepLast(10), rmw_qos_profile_default), const rclcpp::PublisherOptions &options=rclcpp::PublisherOptions()) noexcept
	Advertise ROS topic.

Connection	connect_to_source (Source< Inputs... > &src) noexcept
	Connect this sink to a source.

virtual void	disconnect () noexcept override
	Disconnect from all connected sources.

void	disconnect_from_all_sources () noexcept
	Disconnect from all connected sources.

virtual bool	is_active () const noexcept override
	Check if the ROS publisher has at least one subscriber.

virtual void	reset () noexcept
	Reset filter state.

virtual std::string	topic () const noexcept override
	Return the configured ROS topic.

Static Public Attributes
static constexpr std::size_t	NUM_INPUTS = sizeof...(Inputs)
	Number of input arguments.

Protected Member Functions
std::tuple< Connection, Connection >	link_with_subscriber (SubscriberBase &sub)
	Add a new subscriber that will be controlled by this publisher.

virtual void	receive (helpers::argument_t< Inputs >... in)=0
	Process incoming data.

void	shutdown_monitor () noexcept
	Shutdown monitoring thread for the number of subscribers.

void	start_monitor (const rclcpp::Node::SharedPtr &node) noexcept
	Start monitoring thread for the number of subscribers.

void	update_subscriber_state ()
	Cause all linked subscribers to subscribe or unsubscribe to their ROS topics.

Detailed Description

template<class M, template< typename > class Translate = RosMessageSharedPtr>
class fkie_message_filters::Publisher< M, Translate >

Publish consumed data on a ROS topic.

This class together with the Subscriber class is the generic interface between ROS and this library. All messages which are received from the connected sources will be published on the advertised ROS topic. For maximum flexibility, you can choose how to receive messages from your sources:

Publisher<M, RosMessageSharedPtr> will act as a sink of M::ConstSharedPtr objects (default)
Publisher<M, RosMessageUniquePtr> will act as a sink of M::UniquePtr objects
Publisher<M, RosMessage> will act as a sink of plain M objects

Unlike regular ROS publishers, this class can be associated with one or more subscriber instances. In that case, the subscribers will subscribe to their ROS topics only if the publisher is actively used. This is a convenient method to save processing power if the filter pipeline is used only intermittently.

See also: CameraPublisher, ImagePublisher

Member Typedef Documentation

◆ Input

template<typename... Inputs>

using fkie_message_filters::Sink< Inputs >::Input = IO<Inputs...>

inherited

Grouped input types.

This type can be used to define sources with matching types.

Constructor & Destructor Documentation

◆ Publisher() [1/2]

template<class M , template< typename > class Translate>

FKIE_ML_BEGIN_ABI_NAMESPACE fkie_message_filters::Publisher< M, Translate >::Publisher ( )

noexcept

Constructs an empty publisher.

You need to call advertise() to actually publish to a ROS topic.

Exceptions: Does not throw any exceptions.

◆ Publisher() [2/2]

template<class M , template< typename > class Translate>

fkie_message_filters::Publisher< M, Translate >::Publisher	(	rclcpp::Node::SharedPtr &	node,
		const std::string &	topic,
		const rclcpp::QoS &	qos = `rclcpp::QoS(rclcpp::KeepLast(10), rmw_qos_profile_default)`,
		const rclcpp::PublisherOptions &	options = `rclcpp::PublisherOptions()`
	)

noexcept

Constructor that advertises the given ROS topic.

The constructor calls advertise() for you.

Exceptions: Does not throw any exceptions.

Member Function Documentation

◆ advertise()

template<class M , template< typename > class Translate>

void fkie_message_filters::Publisher< M, Translate >::advertise	(	rclcpp::Node::SharedPtr &	node,
		const std::string &	topic,
		const rclcpp::QoS &	qos = `rclcpp::QoS(rclcpp::KeepLast(10), rmw_qos_profile_default)`,
		const rclcpp::PublisherOptions &	options = `rclcpp::PublisherOptions()`
	)

noexcept

Advertise ROS topic.

All arguments are passed to the ROS client library; see the ROS documentation for further information. Calling this method will automatically unadvertise any previously advertised ROS topic.

node ROS node instance to create the ROS publisher
topic name of the ROS topic, subject to remapping
qos the ROS quality of service specification
options ROS publisher options

Exceptions: Does not throw any exceptions.

◆ connect_to_source()

template<typename... Inputs>

Connection fkie_message_filters::Sink< Inputs >::connect_to_source ( Source< Inputs... > & src )

noexceptinherited

Connect this sink to a source.

Can be called multiple times to connect multiple sources; in that case, the sink receives data from all connected sources. This function does basically the same thing as Source::connect_to_sink(), only from the opposite point of view.

src the source that is to be connected

Returns: a connection object that can be used to monitor or sever the created connection

Exceptions: Does not throw any exceptions.

◆ disconnect()

template<typename... Inputs>

void fkie_message_filters::Sink< Inputs >::disconnect ( )

overridevirtualnoexceptinherited

Disconnect from all connected sources.

The sink implementation calls disconnect_from_all_sources().

Exceptions: Does not throw any exceptions.

Implements fkie_message_filters::FilterBase.

Reimplemented in fkie_message_filters::Divider< Inputs >, fkie_message_filters::Filter< In, Out >, fkie_message_filters::Filter< IO< Inputs... >, IO< Inputs... > >, fkie_message_filters::Filter< IO< Inputs... >, IO< Inputs... >::template Select< Is... > >, and fkie_message_filters::Filter< IO< Inputs... >, IO< Outputs... > >.

◆ disconnect_from_all_sources()

template<typename... Inputs>

void fkie_message_filters::Sink< Inputs >::disconnect_from_all_sources ( )

noexceptinherited

Disconnect from all connected sources.

Severs the connection to all sources. The receive() method will not be called any more.

Exceptions: Does not throw any exceptions.

◆ is_active()

template<class M , template< typename > class Translate>

bool fkie_message_filters::Publisher< M, Translate >::is_active ( ) const

overridevirtualnoexcept

Check if the ROS publisher has at least one subscriber.

node ROS node instance to create the ROS publisher
topic name of the ROS topic, subject to remapping
qos the ROS quality of service specification
options ROS publisher options

Exceptions: Does not throw any exceptions.

Implements fkie_message_filters::PublisherBase.

◆ link_with_subscriber()

std::tuple< Connection, Connection > fkie_message_filters::PublisherBase::link_with_subscriber ( SubscriberBase & sub )

protectedinherited

Add a new subscriber that will be controlled by this publisher.

sub the subscriber
Returns
two connection objects for the signal to enable and disable the linked subscriber

Exceptions
Propagates exceptions raised by the implementation of the abstract class methods.

◆ receive()

template<typename... Inputs>

virtual void fkie_message_filters::Sink< Inputs >::receive ( helpers::argument_t< Inputs >... in )

protectedpure virtualinherited

Process incoming data.

Derived classes need to override this method to handle all data that is to be consumed by the sink.

Exceptions: Depends on the implementation.

Implemented in fkie_message_filters::Buffer< Inputs >, fkie_message_filters::Divider< Inputs >, fkie_message_filters::Selector< Inputs, Is >, fkie_message_filters::Sequencer< Inputs >, fkie_message_filters::SimpleUserFilter< Inputs >, fkie_message_filters::TfFilter< Inputs >, fkie_message_filters::TfFilter< Inputs... >, and fkie_message_filters::UserFilter< Inputs, Outputs >.

◆ reset()

virtual void fkie_message_filters::FilterBase::reset ( )

inlinevirtualnoexceptinherited

Reset filter state.

For stateful filters, this method resets the internal state as if the filter had just been created. Existing connections to sources and sinks are unaffected.

The default implementation does nothing.

Exceptions: Does not throw any exceptions.

Reimplemented in fkie_message_filters::Buffer< Inputs >, fkie_message_filters::Combiner< PolicyTmpl, IOs >, fkie_message_filters::Sequencer< Inputs >, fkie_message_filters::TfFilter< Inputs >, and fkie_message_filters::TfFilter< Inputs... >.

◆ shutdown_monitor()

void fkie_message_filters::PublisherBase::shutdown_monitor ( )

protectednoexceptinherited

Shutdown monitoring thread for the number of subscribers.

This function is called automatically when the publisher object is destroyed.

◆ start_monitor()

void fkie_message_filters::PublisherBase::start_monitor ( const rclcpp::Node::SharedPtr & node )

protectednoexceptinherited

Start monitoring thread for the number of subscribers.

This is needed in ROS 2 because there is no longer a dedicated callback for created publishers.

Exceptions: Does not throw any exceptions.

◆ topic()

template<class M , template< typename > class Translate>

std::string fkie_message_filters::Publisher< M, Translate >::topic ( ) const

overridevirtualnoexcept

Return the configured ROS topic.

Exceptions: Does not throw any exceptions.

Implements fkie_message_filters::PublisherBase.

◆ update_subscriber_state()

void fkie_message_filters::PublisherBase::update_subscriber_state ( )

protectedinherited

Cause all linked subscribers to subscribe or unsubscribe to their ROS topics.

This will check the return value of is_active() to determine if the publisher is active, and then call SubscriberBase::subscribe_impl() or SubscriberBase::unsubscribe_impl() accordingly.

Exceptions: Propagates exceptions raised by the implementation of the abstract class methods.

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

include/fkie_message_filters/publisher.hpp
include/fkie_message_filters/publisher_impl.hpp

Public Types

Public Member Functions

Static Public Attributes

Protected Member Functions

Detailed Description

Member Typedef Documentation

◆ Input

Constructor & Destructor Documentation

◆ Publisher() [1/2]

◆ Publisher() [2/2]

Member Function Documentation

◆ advertise()

◆ connect_to_source()

◆ disconnect()

◆ disconnect_from_all_sources()

◆ is_active()

◆ link_with_subscriber()

◆ receive()

◆ reset()

◆ shutdown_monitor()

◆ start_monitor()

◆ topic()

◆ update_subscriber_state()