Subscribe to a ROS topic as data provider. More...

#include <subscriber.h>

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

Public Member Functions
void	set_subscribe_options (ros::NodeHandle &nh, const std::string &topic, uint32_t queue_size, const ros::TransportHints &transport_hints=ros::TransportHints(), ros::CallbackQueueInterface *callback_queue=nullptr) noexcept
	Configure ROS topic that is to be subscribed. More...

virtual void	subscribe ()
	Subscribe to the configured ROS topic. More...

void	subscribe (ros::NodeHandle &nh, const std::string &topic, uint32_t queue_size, const ros::TransportHints &transport_hints=ros::TransportHints(), ros::CallbackQueueInterface *callback_queue=nullptr) noexcept
	Convenience function to subscribe to a ROS topic. More...

virtual void	subscribe_on_demand (PublisherBase &pub)
	Subscribe to the configured ROS topic whenever the given publisher is active. More...

	Subscriber () noexcept
	Constructs an empty subscriber. More...

	Subscriber (ros::NodeHandle &nh, const std::string &topic, uint32_t queue_size, const ros::TransportHints &transport_hints=ros::TransportHints(), ros::CallbackQueueInterface *callback_queue=nullptr) noexcept
	Constructor that subscribes to the given ROS topic. More...

virtual std::string	topic () const noexcept override
	Return the subscribed topic name. More...

virtual void	unsubscribe ()
	Unsubscribe from the configured ROS topic. More...

Public Member Functions inherited from fkie_message_filters::SubscriberBase
virtual void	subscribe ()
	Subscribe to the configured ROS topic. More...

virtual void	subscribe_on_demand (PublisherBase &pub)
	Subscribe to the configured ROS topic whenever the given publisher is active. More...

virtual void	unsubscribe ()
	Unsubscribe from the configured ROS topic. More...

virtual	~SubscriberBase ()

Public Member Functions inherited from fkie_message_filters::Source< RosMessageEvent< M >::FilterType >
Connection	connect_to_sink (Sink< Outputs... > &dst) noexcept
	Connect this source to a sink. More...

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

void	disconnect_from_all_sinks () noexcept
	Disconnect from all connected sinks. More...

virtual	~Source ()

Protected Member Functions
virtual bool	is_configured () const noexcept override
	Check if the ROS subscriber is properly configured. More...

virtual void	subscribe_impl () noexcept override
	Create a ROS subscriber. More...

virtual void	unsubscribe_impl () noexcept override
	Shut the ROS subscriber down. More...

Protected Member Functions inherited from fkie_message_filters::SubscriberBase
void	link_with_publisher (PublisherBase &pub)
	Add self to the list of subscribers which are controlled by a publisher. More...

void	unlink_from_publisher ()
	Remove self from the list of subscribers which are controlled by a publisher. More...

Protected Member Functions inherited from fkie_message_filters::Source< RosMessageEvent< M >::FilterType >
void	send (const Outputs &... out)
	Pass data to all connected sinks. More...

Private Types
using	EventType = typename Translate< M >::EventType

using	FilterType = typename Translate< M >::FilterType

Private Member Functions
void	cb (const EventType &event)

Private Attributes
std::shared_ptr< ros::NodeHandle >	nh_

ros::SubscribeOptions	opts_

ros::Subscriber	sub_

Additional Inherited Members
Public Types inherited from fkie_message_filters::Source< RosMessageEvent< M >::FilterType >
using	Output = IO< Outputs... >
	Grouped output types. More...

Static Public Attributes inherited from fkie_message_filters::Source< RosMessageEvent< M >::FilterType >
static constexpr std::size_t	NUM_OUTPUTS
	Number of output arguments. More...

Detailed Description

template<class M, template< typename > class Translate = RosMessageEvent>
class fkie_message_filters::Subscriber< M, Translate >

Subscribe to a ROS topic as data provider.

This class together with the Publisher class is the generic interface between ROS and this library. All messages which are received on the subscribed topic will be passed to the connected sinks for further processing. For maximum flexibility, you can choose one of four ways how to pass the received message:

Subscriber<M, RosMessageEvent> will act as a source of ros::MessageEvent<const M> objects (default)
Subscriber<M, RosMessageConstPtr> will act as a source of M::ConstPtr objects (as of this writing, this is a boost::shared_ptr<const M>)
Subscriber<M, RosMessageStdSharedPtr> will act as a source of std::shared_ptr<const M> objects
Subscriber<M, RosMessage> will act as a source of plain M objects

Unlike regular ROS subscribers, this class can be associated with a publisher instance. In that case, the subscriber will delay subscription until the publisher is actively used and will unsubscribe (and stop passing data) as soon as the publisher becomes idle. This is a convenient method to save processing power if the filter pipeline is used only intermittently.

See also: CameraSubscriber, ImageSubscriber

Definition at line 72 of file subscriber.h.

Member Typedef Documentation

◆ EventType

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

using fkie_message_filters::Subscriber< M, Translate >::EventType = typename Translate<M>::EventType

private

Definition at line 161 of file subscriber.h.

◆ FilterType

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

using fkie_message_filters::Subscriber< M, Translate >::FilterType = typename Translate<M>::FilterType

private

Definition at line 162 of file subscriber.h.

Constructor & Destructor Documentation

◆ Subscriber() [1/2]

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

fkie_message_filters::Subscriber< M, Translate >::Subscriber

noexcept

Constructs an empty subscriber.

You need to call set_subscribe_options() and either subscribe() or subscribe_on_demand() to actually subscribe to a ROS topic.

\nothrow

Definition at line 47 of file subscriber_impl.h.

◆ Subscriber() [2/2]

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

fkie_message_filters::Subscriber< M, Translate >::Subscriber	(	ros::NodeHandle &	nh,
		const std::string &	topic,
		uint32_t	queue_size,
		const ros::TransportHints &	transport_hints = `ros::TransportHints()`,
		ros::CallbackQueueInterface *	callback_queue = `nullptr`
	)

noexcept

Constructor that subscribes to the given ROS topic.

This constructor calls set_subscribe_options() and subscribe() for you.

nh ROS node handle to create the ROS subscription
topic name of the ROS topic, subject to remapping
queue_size size of the ROS subscription queue
transport_hints low-level transport hints for the ROS client library
callback_queue custom ROS callback queue

\nothrow

Definition at line 52 of file subscriber_impl.h.

Member Function Documentation

◆ cb()

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

void fkie_message_filters::Subscriber< M, Translate >::cb ( const EventType & event )

private

Definition at line 106 of file subscriber_impl.h.

◆ is_configured()

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

bool fkie_message_filters::Subscriber< M, Translate >::is_configured

overrideprotectedvirtualnoexcept

Check if the ROS subscriber is properly configured.

\nothrow

Implements fkie_message_filters::SubscriberBase.

Definition at line 85 of file subscriber_impl.h.

◆ set_subscribe_options()

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

void fkie_message_filters::Subscriber< M, Translate >::set_subscribe_options	(	ros::NodeHandle &	nh,
		const std::string &	topic,
		uint32_t	queue_size,
		const ros::TransportHints &	transport_hints = `ros::TransportHints()`,
		ros::CallbackQueueInterface *	callback_queue = `nullptr`
	)

noexcept

Configure ROS topic that is to be subscribed.

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

nh ROS node handle to create the ROS subscription
topic name of the ROS topic, subject to remapping
queue_size size of the ROS subscription queue
transport_hints low-level transport hints for the ROS client library
callback_queue custom ROS callback queue

\nothrow

Definition at line 64 of file subscriber_impl.h.

◆ subscribe() [1/2]

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

void fkie_message_filters::SubscriberBase::subscribe

Subscribe to the configured ROS topic.

This method does nothing if no ROS topic was configured or if the subscriber is subscribed already. Cancels the effect of subscribe_on_demand(), i.e. the subscriber will remain subscribed permanently.

\implthrow

Definition at line 64 of file publisher_subscriber_base.cpp.

◆ subscribe() [2/2]

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

void fkie_message_filters::Subscriber< M, Translate >::subscribe	(	ros::NodeHandle &	nh,
		const std::string &	topic,
		uint32_t	queue_size,
		const ros::TransportHints &	transport_hints = `ros::TransportHints()`,
		ros::CallbackQueueInterface *	callback_queue = `nullptr`
	)

noexcept

Convenience function to subscribe to a ROS topic.

This function is equivalent to calling set_subscribe_options() and then subscribe().

nh ROS node handle to create the ROS subscription
topic name of the ROS topic, subject to remapping
queue_size size of the ROS subscription queue
transport_hints low-level transport hints for the ROS client library
callback_queue custom ROS callback queue

\nothrow

Definition at line 77 of file subscriber_impl.h.

◆ subscribe_impl()

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

void fkie_message_filters::Subscriber< M, Translate >::subscribe_impl

overrideprotectedvirtualnoexcept

Create a ROS subscriber.

\nothrow

Implements fkie_message_filters::SubscriberBase.

Definition at line 91 of file subscriber_impl.h.

◆ subscribe_on_demand()

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

void fkie_message_filters::SubscriberBase::subscribe_on_demand

Subscribe to the configured ROS topic whenever the given publisher is active.

This method does nothing if no ROS topic was configured. Otherwise, it will immediately subscribe or unsubscribe depending on the publisher's current state. If the publisher becomes active or inactive, the subscriber's state will update accordingly.

pub publisher

\implthrow

Definition at line 76 of file publisher_subscriber_base.cpp.

◆ topic()

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

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

overridevirtualnoexcept

Return the subscribed topic name.

\abstractthrow

Implements fkie_message_filters::SubscriberBase.

Definition at line 58 of file subscriber_impl.h.

◆ unsubscribe()

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

void fkie_message_filters::SubscriberBase::unsubscribe

Unsubscribe from the configured ROS topic.

You can call subscribe() afterwards to re-subscribe to the ROS topic. This method does nothing if the subscriber is not subscribed to any ROS topic. Cancels the effect of subscribe_on_demand(), i.e. the subscriber will remain unsubscribed permanently.

\implthrow

Definition at line 70 of file publisher_subscriber_base.cpp.

◆ unsubscribe_impl()

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

void fkie_message_filters::Subscriber< M, Translate >::unsubscribe_impl

overrideprotectedvirtualnoexcept

Shut the ROS subscriber down.

\nothrow

Implements fkie_message_filters::SubscriberBase.

Definition at line 100 of file subscriber_impl.h.

Member Data Documentation

◆ nh_

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

std::shared_ptr<ros::NodeHandle> fkie_message_filters::Subscriber< M, Translate >::nh_

private

Definition at line 166 of file subscriber.h.

◆ opts_

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

ros::SubscribeOptions fkie_message_filters::Subscriber< M, Translate >::opts_

private

Definition at line 165 of file subscriber.h.

◆ sub_

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

ros::Subscriber fkie_message_filters::Subscriber< M, Translate >::sub_

private

Definition at line 164 of file subscriber.h.

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

Public Member Functions

Protected Member Functions

Private Types

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

template<class M, template< typename > class Translate = RosMessageEvent> class fkie_message_filters::Subscriber< M, Translate >

Member Typedef Documentation

◆ EventType

◆ FilterType

Constructor & Destructor Documentation

◆ Subscriber() [1/2]

◆ Subscriber() [2/2]

Member Function Documentation

◆ cb()

◆ is_configured()

◆ set_subscribe_options()

◆ subscribe() [1/2]

◆ subscribe() [2/2]

◆ subscribe_impl()

◆ subscribe_on_demand()

◆ topic()

◆ unsubscribe()

◆ unsubscribe_impl()

Member Data Documentation

◆ nh_

◆ opts_

◆ sub_

template<class M, template< typename > class Translate = RosMessageEvent>
class fkie_message_filters::Subscriber< M, Translate >