rclcpp::Node Class Reference

Node is the single point of entry for creating publishers and subscribers. More...

#include <node.hpp>

Inheritance diagram for rclcpp::Node:

Collaboration diagram for rclcpp::Node:

Public Member Functions
	Node (const std::string &node_name, const std::string &namespace_="", bool use_intra_process_comms=false)
	Create a new node with the specified name. More...
	Node (const std::string &node_name, const std::string &namespace_, rclcpp::Context::SharedPtr context, const std::vector< std::string > &arguments, const std::vector< Parameter > &initial_parameters, bool use_global_arguments=true, bool use_intra_process_comms=false, bool start_parameter_services=true)
	Create a node based on the node name and a rclcpp::Context. More...
virtual	~Node ()
const char *	get_name () const
	Get the name of the node. More...
const char *	get_namespace () const
	Get the namespace of the node. More...
rclcpp::Logger	get_logger () const
	Get the logger of the node. More...
rclcpp::callback_group::CallbackGroup::SharedPtr	create_callback_group (rclcpp::callback_group::CallbackGroupType group_type)
	Create and return a callback group. More...
const std::vector< rclcpp::callback_group::CallbackGroup::WeakPtr > &	get_callback_groups () const
	Return the list of callback groups in the node. More...
template<typename MessageT , typename Alloc = std::allocator<void>, typename PublisherT = ::rclcpp::Publisher<MessageT, Alloc>>
std::shared_ptr< PublisherT >	create_publisher (const std::string &topic_name, size_t qos_history_depth, std::shared_ptr< Alloc > allocator=nullptr)
	Create and return a Publisher. More...
template<typename MessageT , typename Alloc = std::allocator<void>, typename PublisherT = ::rclcpp::Publisher<MessageT, Alloc>>
std::shared_ptr< PublisherT >	create_publisher (const std::string &topic_name, const rmw_qos_profile_t &qos_profile=rmw_qos_profile_default, std::shared_ptr< Alloc > allocator=nullptr)
	Create and return a Publisher. More...
template<typename MessageT , typename CallbackT , typename Alloc = std::allocator<void>, typename SubscriptionT = rclcpp::Subscription< typename rclcpp::subscription_traits::has_message_type<CallbackT>::type, Alloc>>
std::shared_ptr< SubscriptionT >	create_subscription (const std::string &topic_name, CallbackT &&callback, const rmw_qos_profile_t &qos_profile=rmw_qos_profile_default, rclcpp::callback_group::CallbackGroup::SharedPtr group=nullptr, bool ignore_local_publications=false, typename rclcpp::message_memory_strategy::MessageMemoryStrategy< typename rclcpp::subscription_traits::has_message_type< CallbackT >::type, Alloc >::SharedPtr msg_mem_strat=nullptr, std::shared_ptr< Alloc > allocator=nullptr)
	Create and return a Subscription. More...
template<typename MessageT , typename CallbackT , typename Alloc = std::allocator<void>, typename SubscriptionT = rclcpp::Subscription< typename rclcpp::subscription_traits::has_message_type<CallbackT>::type, Alloc>>
std::shared_ptr< SubscriptionT >	create_subscription (const std::string &topic_name, CallbackT &&callback, size_t qos_history_depth, rclcpp::callback_group::CallbackGroup::SharedPtr group=nullptr, bool ignore_local_publications=false, typename rclcpp::message_memory_strategy::MessageMemoryStrategy< typename rclcpp::subscription_traits::has_message_type< CallbackT >::type, Alloc >::SharedPtr msg_mem_strat=nullptr, std::shared_ptr< Alloc > allocator=nullptr)
	Create and return a Subscription. More...
template<typename DurationT = std::milli, typename CallbackT >
rclcpp::WallTimer< CallbackT >::SharedPtr	create_wall_timer (std::chrono::duration< int64_t, DurationT > period, CallbackT callback, rclcpp::callback_group::CallbackGroup::SharedPtr group=nullptr)
	Create a timer. More...
template<typename ServiceT >
rclcpp::Client< ServiceT >::SharedPtr	create_client (const std::string &service_name, const rmw_qos_profile_t &qos_profile=rmw_qos_profile_services_default, rclcpp::callback_group::CallbackGroup::SharedPtr group=nullptr)
template<typename ServiceT , typename CallbackT >
rclcpp::Service< ServiceT >::SharedPtr	create_service (const std::string &service_name, CallbackT &&callback, const rmw_qos_profile_t &qos_profile=rmw_qos_profile_services_default, rclcpp::callback_group::CallbackGroup::SharedPtr group=nullptr)
std::vector< rcl_interfaces::msg::SetParametersResult >	set_parameters (const std::vector< rclcpp::Parameter > &parameters)
rcl_interfaces::msg::SetParametersResult	set_parameters_atomically (const std::vector< rclcpp::Parameter > &parameters)
template<typename ParameterT >
void	set_parameter_if_not_set (const std::string &name, const ParameterT &value)
template<typename MapValueT >
void	set_parameters_if_not_set (const std::string &name, const std::map< std::string, MapValueT > &values)
	Set a map of parameters with the same prefix. More...
std::vector< rclcpp::Parameter >	get_parameters (const std::vector< std::string > &names) const
rclcpp::Parameter	get_parameter (const std::string &name) const
bool	get_parameter (const std::string &name, rclcpp::Parameter &parameter) const
template<typename ParameterT >
bool	get_parameter (const std::string &name, ParameterT &parameter) const
	Assign the value of the parameter if set into the parameter argument. More...
template<typename MapValueT >
bool	get_parameters (const std::string &name, std::map< std::string, MapValueT > &values) const
	Assign the value of the map parameter if set into the values argument. More...
template<typename ParameterT >
bool	get_parameter_or (const std::string &name, ParameterT &value, const ParameterT &alternative_value) const
	Get the parameter value, or the "alternative value" if not set, and assign it to "value". More...
template<typename ParameterT >
void	get_parameter_or_set (const std::string &name, ParameterT &value, const ParameterT &alternative_value)
	Get the parameter value; if not set, set the "alternative value" and store it in the node. More...
std::vector< rcl_interfaces::msg::ParameterDescriptor >	describe_parameters (const std::vector< std::string > &names) const
std::vector< uint8_t >	get_parameter_types (const std::vector< std::string > &names) const
rcl_interfaces::msg::ListParametersResult	list_parameters (const std::vector< std::string > &prefixes, uint64_t depth) const
template<typename CallbackT >
void	register_param_change_callback (CallbackT &&callback)
	Register the callback for parameter changes. More...
std::vector< std::string >	get_node_names () const
std::map< std::string, std::vector< std::string > >	get_topic_names_and_types () const
std::map< std::string, std::vector< std::string > >	get_service_names_and_types () const
size_t	count_publishers (const std::string &topic_name) const
size_t	count_subscribers (const std::string &topic_name) const
rclcpp::Event::SharedPtr	get_graph_event ()
	Return a graph event, which will be set anytime a graph change occurs. More...
void	wait_for_graph_change (rclcpp::Event::SharedPtr event, std::chrono::nanoseconds timeout)
	Wait for a graph event to occur by waiting on an Event to become set. More...
rclcpp::Clock::SharedPtr	get_clock ()
Time	now ()
rclcpp::node_interfaces::NodeBaseInterface::SharedPtr	get_node_base_interface ()
	Return the Node's internal NodeBaseInterface implementation. More...
rclcpp::node_interfaces::NodeClockInterface::SharedPtr	get_node_clock_interface ()
	Return the Node's internal NodeClockInterface implementation. More...
rclcpp::node_interfaces::NodeGraphInterface::SharedPtr	get_node_graph_interface ()
	Return the Node's internal NodeGraphInterface implementation. More...
rclcpp::node_interfaces::NodeLoggingInterface::SharedPtr	get_node_logging_interface ()
	Return the Node's internal NodeLoggingInterface implementation. More...
rclcpp::node_interfaces::NodeTimersInterface::SharedPtr	get_node_timers_interface ()
	Return the Node's internal NodeTimersInterface implementation. More...
rclcpp::node_interfaces::NodeTopicsInterface::SharedPtr	get_node_topics_interface ()
	Return the Node's internal NodeTopicsInterface implementation. More...
rclcpp::node_interfaces::NodeServicesInterface::SharedPtr	get_node_services_interface ()
	Return the Node's internal NodeServicesInterface implementation. More...
rclcpp::node_interfaces::NodeWaitablesInterface::SharedPtr	get_node_waitables_interface ()
	Return the Node's internal NodeWaitablesInterface implementation. More...
rclcpp::node_interfaces::NodeParametersInterface::SharedPtr	get_node_parameters_interface ()
	Return the Node's internal NodeParametersInterface implementation. More...
rclcpp::node_interfaces::NodeTimeSourceInterface::SharedPtr	get_node_time_source_interface ()
	Return the Node's internal NodeParametersInterface implementation. More...
template<typename ServiceT >
Client< ServiceT >::SharedPtr	create_client (const std::string &service_name, const rmw_qos_profile_t &qos_profile, rclcpp::callback_group::CallbackGroup::SharedPtr group)
Public Member Functions inherited from std::enable_shared_from_this< Node >
T	enable_shared_from_this (T... args)
T	operator= (T... args)
T	shared_from_this (T... args)
T	~enable_shared_from_this (T... args)

Detailed Description

Node is the single point of entry for creating publishers and subscribers.

Constructor & Destructor Documentation

Node() [1/2]

rclcpp::Node::Node ( const std::string &  node_name, const std::string &  namespace_ = "", bool  use_intra_process_comms = false  )

explicit

Create a new node with the specified name.

Parameters

[in]	node_name	Name of the node.
[in]	namespace_	Namespace of the node.
[in]	use_intra_process_comms	True to use the optimized intra-process communication pipeline to pass messages between nodes in the same process using shared memory.

Node() [2/2]

rclcpp::Node::Node	(	const std::string &	node_name,
		const std::string &	namespace_,
		rclcpp::Context::SharedPtr	context,
		const std::vector< std::string > &	arguments,
		const std::vector< Parameter > &	initial_parameters,
		bool	use_global_arguments = true,
		bool	use_intra_process_comms = false,
		bool	start_parameter_services = true
	)

Create a node based on the node name and a rclcpp::Context.

Parameters

[in]	node_name	Name of the node.
[in]	namespace_	Namespace of the node.
[in]	context	The context for the node (usually represents the state of a process).
[in]	arguments	Command line arguments that should apply only to this node.
[in]	initial_parameters	a list of initial values for parameters on the node. This can be used to provide remapping rules that only affect one instance.
[in]	use_global_arguments	False to prevent node using arguments passed to the process.
[in]	use_intra_process_comms	True to use the optimized intra-process communication pipeline to pass messages between nodes in the same process using shared memory.
[in]	start_parameter_services	True to setup ROS interfaces for accessing parameters in the node.

~Node()

virtual rclcpp::Node::~Node ( )

virtual

Member Function Documentation

get_name()

const char* rclcpp::Node::get_name

(

)

const

Get the name of the node.

Returns

The name of the node.

get_namespace()

const char* rclcpp::Node::get_namespace

(

)

const

Get the namespace of the node.

Returns

The namespace of the node.

get_logger()

rclcpp::Logger rclcpp::Node::get_logger

(

)

const

Get the logger of the node.

Returns

The logger of the node.

create_callback_group()

rclcpp::callback_group::CallbackGroup::SharedPtr rclcpp::Node::create_callback_group

(

rclcpp::callback_group::CallbackGroupType

group_type

)

Create and return a callback group.

get_callback_groups()

const std::vector<rclcpp::callback_group::CallbackGroup::WeakPtr>& rclcpp::Node::get_callback_groups

(

)

const

Return the list of callback groups in the node.

create_publisher() [1/2]

template<typename MessageT , typename Alloc , typename PublisherT >

std::shared_ptr< PublisherT > rclcpp::Node::create_publisher	(	const std::string &	topic_name,
		size_t	qos_history_depth,
		std::shared_ptr< Alloc >	allocator = nullptr
	)

Create and return a Publisher.

Parameters

[in]	topic_name	The topic for this publisher to publish on.
[in]	qos_history_depth	The depth of the publisher message queue.
[in]	allocator	Optional custom allocator.

Returns

Shared pointer to the created publisher.

create_publisher() [2/2]

template<typename MessageT , typename Alloc , typename PublisherT >

std::shared_ptr< PublisherT > rclcpp::Node::create_publisher	(	const std::string &	topic_name,
		const rmw_qos_profile_t &	qos_profile = rmw_qos_profile_default,
		std::shared_ptr< Alloc >	allocator = nullptr
	)

Create and return a Publisher.

Parameters

[in]	topic_name	The topic for this publisher to publish on.
[in]	qos_profile	The quality of service profile to pass on to the rmw implementation.
[in]	allocator	Optional custom allocator.

Returns

Shared pointer to the created publisher.

create_subscription() [1/2]

template<typename MessageT , typename CallbackT , typename Alloc , typename SubscriptionT >

std::shared_ptr< SubscriptionT > rclcpp::Node::create_subscription	(	const std::string &	topic_name,
		CallbackT &&	callback,
		const rmw_qos_profile_t &	qos_profile = rmw_qos_profile_default,
		rclcpp::callback_group::CallbackGroup::SharedPtr	group = nullptr,
		bool	ignore_local_publications = false,
		typename rclcpp::message_memory_strategy::MessageMemoryStrategy< typename rclcpp::subscription_traits::has_message_type< CallbackT >::type, Alloc >::SharedPtr	msg_mem_strat = nullptr,
		std::shared_ptr< Alloc >	allocator = nullptr
	)

Create and return a Subscription.

Parameters

[in]	topic_name	The topic to subscribe on.
[in]	callback	The user-defined callback function.
[in]	qos_profile	The quality of service profile to pass on to the rmw implementation.
[in]	group	The callback group for this subscription. NULL for no callback group.
[in]	ignore_local_publications	True to ignore local publications.
[in]	msg_mem_strat	The message memory strategy to use for allocating messages.
[in]	allocator	Optional custom allocator.

Returns

Shared pointer to the created subscription.

create_subscription() [2/2]

template<typename MessageT , typename CallbackT , typename Alloc , typename SubscriptionT >

std::shared_ptr< SubscriptionT > rclcpp::Node::create_subscription	(	const std::string &	topic_name,
		CallbackT &&	callback,
		size_t	qos_history_depth,
		rclcpp::callback_group::CallbackGroup::SharedPtr	group = nullptr,
		bool	ignore_local_publications = false,
		typename rclcpp::message_memory_strategy::MessageMemoryStrategy< typename rclcpp::subscription_traits::has_message_type< CallbackT >::type, Alloc >::SharedPtr	msg_mem_strat = nullptr,
		std::shared_ptr< Alloc >	allocator = nullptr
	)

Create and return a Subscription.

Parameters

[in]	topic_name	The topic to subscribe on.
[in]	qos_history_depth	The depth of the subscription's incoming message queue.
[in]	callback	The user-defined callback function.
[in]	group	The callback group for this subscription. NULL for no callback group.
[in]	ignore_local_publications	True to ignore local publications.
[in]	msg_mem_strat	The message memory strategy to use for allocating messages.
[in]	allocator	Optional custom allocator.

Returns

Shared pointer to the created subscription.

create_wall_timer()

template<typename DurationT , typename CallbackT >

rclcpp::WallTimer< CallbackT >::SharedPtr rclcpp::Node::create_wall_timer	(	std::chrono::duration< int64_t, DurationT >	period,
		CallbackT	callback,
		rclcpp::callback_group::CallbackGroup::SharedPtr	group = nullptr
	)

Create a timer.

Parameters

[in]	period	Time interval between triggers of the callback.
[in]	callback	User-defined callback function.
[in]	group	Callback group to execute this timer's callback in.

create_client() [1/2]

template<typename ServiceT >

rclcpp::Client<ServiceT>::SharedPtr rclcpp::Node::create_client	(	const std::string &	service_name,
		const rmw_qos_profile_t &	qos_profile = rmw_qos_profile_services_default,
		rclcpp::callback_group::CallbackGroup::SharedPtr	group = nullptr
	)

create_service()

template<typename ServiceT , typename CallbackT >

rclcpp::Service< ServiceT >::SharedPtr rclcpp::Node::create_service	(	const std::string &	service_name,
		CallbackT &&	callback,
		const rmw_qos_profile_t &	qos_profile = rmw_qos_profile_services_default,
		rclcpp::callback_group::CallbackGroup::SharedPtr	group = nullptr
	)

set_parameters()

std::vector<rcl_interfaces::msg::SetParametersResult> rclcpp::Node::set_parameters

(

const std::vector< rclcpp::Parameter > &

parameters

)

set_parameters_atomically()

rcl_interfaces::msg::SetParametersResult rclcpp::Node::set_parameters_atomically

(

const std::vector< rclcpp::Parameter > &

parameters

)

set_parameter_if_not_set()

template<typename ParameterT >

void rclcpp::Node::set_parameter_if_not_set	(	const std::string &	name,
		const ParameterT &	value
	)

set_parameters_if_not_set()

template<typename MapValueT >

void rclcpp::Node::set_parameters_if_not_set	(	const std::string &	name,
		const std::map< std::string, MapValueT > &	values
	)

Set a map of parameters with the same prefix.

For each key in the map, a parameter with a name of "name.key" will be set to the value in the map.

Parameters

[in]	name	The prefix of the parameters to set.
[in]	values	The parameters to set in the given prefix.

get_parameters() [1/2]

std::vector<rclcpp::Parameter> rclcpp::Node::get_parameters

(

const std::vector< std::string > &

names

)

const

get_parameter() [1/3]

rclcpp::Parameter rclcpp::Node::get_parameter

(

const std::string &

name

)

const

get_parameter() [2/3]

bool rclcpp::Node::get_parameter	(	const std::string &	name,
		rclcpp::Parameter &	parameter
	)		const

get_parameter() [3/3]

template<typename ParameterT >

bool rclcpp::Node::get_parameter	(	const std::string &	name,
		ParameterT &	parameter
	)		const

Assign the value of the parameter if set into the parameter argument.

If the parameter was not set, then the "parameter" argument is never assigned a value.

Parameters

[in]	name	The name of the parameter to get.
[out]	parameter	The output where the value of the parameter should be assigned.

Returns

true if the parameter was set, false otherwise

get_parameters() [2/2]

template<typename MapValueT >

bool rclcpp::Node::get_parameters	(	const std::string &	name,
		std::map< std::string, MapValueT > &	values
	)		const

Assign the value of the map parameter if set into the values argument.

Parameter names that are part of a map are of the form "name.member". This API gets all parameters that begin with "name", storing them into the map with the name of the parameter and their value. If there are no members in the named map, then the "values" argument is not changed.

Parameters

[in]	name	The prefix of the parameters to get.
[out]	values	The map of output values, with one std::string,MapValueT per parameter.

Returns

true if values was changed, false otherwise

get_parameter_or()

template<typename ParameterT >

bool rclcpp::Node::get_parameter_or	(	const std::string &	name,
		ParameterT &	value,
		const ParameterT &	alternative_value
	)		const

Get the parameter value, or the "alternative value" if not set, and assign it to "value".

If the parameter was not set, then the "value" argument is assigned the "alternative_value". In all cases, the parameter remains not set after this function is called.

Parameters

[in]	name	The name of the parameter to get.
[out]	value	The output where the value of the parameter should be assigned.
[in]	alternative_value	Value to be stored in output if the parameter was not set.

Returns

true if the parameter was set, false otherwise

get_parameter_or_set()

template<typename ParameterT >

void rclcpp::Node::get_parameter_or_set	(	const std::string &	name,
		ParameterT &	value,
		const ParameterT &	alternative_value
	)

Get the parameter value; if not set, set the "alternative value" and store it in the node.

If the parameter is set, then the "value" argument is assigned the value in the parameter. If the parameter is not set, then the "value" argument is assigned the "alternative_value", and the parameter is set to the "alternative_value" on the node.

Parameters

[in]	name	The name of the parameter to get.
[out]	value	The output where the value of the parameter should be assigned.
[in]	alternative_value	Value to be stored in output and parameter if the parameter was not set.

describe_parameters()

std::vector<rcl_interfaces::msg::ParameterDescriptor> rclcpp::Node::describe_parameters

(

const std::vector< std::string > &

names

)

const

get_parameter_types()

std::vector<uint8_t> rclcpp::Node::get_parameter_types

(

const std::vector< std::string > &

names

)

const

list_parameters()

rcl_interfaces::msg::ListParametersResult rclcpp::Node::list_parameters	(	const std::vector< std::string > &	prefixes,
		uint64_t	depth
	)		const

register_param_change_callback()

template<typename CallbackT >

void rclcpp::Node::register_param_change_callback

(

CallbackT &&

callback

)

Register the callback for parameter changes.

Parameters

[in]

callback

User defined callback function. It is expected to atomically set parameters.

Note

Repeated invocations of this function will overwrite previous callbacks

get_node_names()

std::vector<std::string> rclcpp::Node::get_node_names

(

)

const

get_topic_names_and_types()

std::map<std::string, std::vector<std::string> > rclcpp::Node::get_topic_names_and_types

(

)

const

get_service_names_and_types()

std::map<std::string, std::vector<std::string> > rclcpp::Node::get_service_names_and_types

(

)

const

count_publishers()

size_t rclcpp::Node::count_publishers

(

const std::string &

topic_name

)

const

count_subscribers()

size_t rclcpp::Node::count_subscribers

(

const std::string &

topic_name

)

const

get_graph_event()

rclcpp::Event::SharedPtr rclcpp::Node::get_graph_event

(

)

Return a graph event, which will be set anytime a graph change occurs.

wait_for_graph_change()

void rclcpp::Node::wait_for_graph_change	(	rclcpp::Event::SharedPtr	event,
		std::chrono::nanoseconds	timeout
	)

Wait for a graph event to occur by waiting on an Event to become set.

The given Event must be acquire through the get_graph_event() method.

Exceptions

InvalidEventError	if the given event is nullptr
EventNotRegisteredError	if the given event was not acquired with get_graph_event().

get_clock()

rclcpp::Clock::SharedPtr rclcpp::Node::get_clock

(

)

now()

Time rclcpp::Node::now

(

)

get_node_base_interface()

rclcpp::node_interfaces::NodeBaseInterface::SharedPtr rclcpp::Node::get_node_base_interface

(

)

Return the Node's internal NodeBaseInterface implementation.

get_node_clock_interface()

rclcpp::node_interfaces::NodeClockInterface::SharedPtr rclcpp::Node::get_node_clock_interface

(

)

Return the Node's internal NodeClockInterface implementation.

get_node_graph_interface()

rclcpp::node_interfaces::NodeGraphInterface::SharedPtr rclcpp::Node::get_node_graph_interface

(

)

Return the Node's internal NodeGraphInterface implementation.

get_node_logging_interface()

rclcpp::node_interfaces::NodeLoggingInterface::SharedPtr rclcpp::Node::get_node_logging_interface

(

)

Return the Node's internal NodeLoggingInterface implementation.

get_node_timers_interface()

rclcpp::node_interfaces::NodeTimersInterface::SharedPtr rclcpp::Node::get_node_timers_interface

(

)

Return the Node's internal NodeTimersInterface implementation.

get_node_topics_interface()

rclcpp::node_interfaces::NodeTopicsInterface::SharedPtr rclcpp::Node::get_node_topics_interface

(

)

Return the Node's internal NodeTopicsInterface implementation.

get_node_services_interface()

rclcpp::node_interfaces::NodeServicesInterface::SharedPtr rclcpp::Node::get_node_services_interface

(

)

Return the Node's internal NodeServicesInterface implementation.

get_node_waitables_interface()

rclcpp::node_interfaces::NodeWaitablesInterface::SharedPtr rclcpp::Node::get_node_waitables_interface

(

)

Return the Node's internal NodeWaitablesInterface implementation.

get_node_parameters_interface()

rclcpp::node_interfaces::NodeParametersInterface::SharedPtr rclcpp::Node::get_node_parameters_interface

(

)

Return the Node's internal NodeParametersInterface implementation.

get_node_time_source_interface()

rclcpp::node_interfaces::NodeTimeSourceInterface::SharedPtr rclcpp::Node::get_node_time_source_interface

(

)

Return the Node's internal NodeParametersInterface implementation.

create_client() [2/2]

template<typename ServiceT >

Client<ServiceT>::SharedPtr rclcpp::Node::create_client	(	const std::string &	service_name,
		const rmw_qos_profile_t &	qos_profile,
		rclcpp::callback_group::CallbackGroup::SharedPtr	group
	)

---

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

• include/rclcpp/node.hpp
• include/rclcpp/node_impl.hpp