Subscription implementation, templated on the type of message this subscription receives. More...

#include <rclcpp/subscription.hpp>

Inheritance diagram for rclcpp::Subscription< MessageT, AllocatorT, SubscribedT, ROSMessageT, MessageMemoryStrategyT >:

Collaboration diagram for rclcpp::Subscription< MessageT, AllocatorT, SubscribedT, ROSMessageT, MessageMemoryStrategyT >:

[legend]

Public Types
using	SubscribedType = SubscribedT

using	ROSMessageType = ROSMessageT

using	MessageMemoryStrategyType = MessageMemoryStrategyT

using	SubscribedTypeAllocatorTraits = allocator::AllocRebind< SubscribedType, AllocatorT >

using	SubscribedTypeAllocator = typename SubscribedTypeAllocatorTraits::allocator_type

using	SubscribedTypeDeleter = allocator::Deleter< SubscribedTypeAllocator, SubscribedType >

using	ROSMessageTypeAllocatorTraits = allocator::AllocRebind< ROSMessageType, AllocatorT >

using	ROSMessageTypeAllocator = typename ROSMessageTypeAllocatorTraits::allocator_type

using	ROSMessageTypeDeleter = allocator::Deleter< ROSMessageTypeAllocator, ROSMessageType >

using	MessageAllocatorTraits = ROSMessageTypeAllocatorTraits

using	MessageAllocator = ROSMessageTypeAllocator

using	MessageDeleter = ROSMessageTypeDeleter

using	ConstMessageSharedPtr = std::shared_ptr< const ROSMessageType >

using	MessageUniquePtr = std::unique_ptr< ROSMessageType, ROSMessageTypeDeleter >

Public Types inherited from rclcpp::SubscriptionBase
using	IntraProcessManagerWeakPtr = std::weak_ptr< rclcpp::experimental::IntraProcessManager >

Public Member Functions
	Subscription (rclcpp::node_interfaces::NodeBaseInterface *node_base, const rosidl_message_type_support_t &type_support_handle, const std::string &topic_name, const rclcpp::QoS &qos, AnySubscriptionCallback< MessageT, AllocatorT > callback, const rclcpp::SubscriptionOptionsWithAllocator< AllocatorT > &options, typename MessageMemoryStrategyT::SharedPtr message_memory_strategy, SubscriptionTopicStatisticsSharedPtr subscription_topic_statistics=nullptr)
	Default constructor. More...

void	post_init_setup (rclcpp::node_interfaces::NodeBaseInterface *node_base, const rclcpp::QoS &qos, const rclcpp::SubscriptionOptionsWithAllocator< AllocatorT > &options)
	Called after construction to continue setup that requires shared_from_this().

bool	take (ROSMessageType &message_out, rclcpp::MessageInfo &message_info_out)
	Take the next message from the inter-process subscription. More...

template<typename TakeT >
std::enable_if_t< !rosidl_generator_traits::is_message< TakeT >::value &&std::is_same_v< TakeT, SubscribedType >, bool >	take (TakeT &message_out, rclcpp::MessageInfo &message_info_out)
	Take the next message from the inter-process subscription. More...

std::shared_ptr< void >	create_message () override
	Borrow a new message. More...

std::shared_ptr< rclcpp::SerializedMessage >	create_serialized_message () override
	Borrow a new serialized message. More...

void	handle_message (std::shared_ptr< void > &message, const rclcpp::MessageInfo &message_info) override
	Check if we need to handle the message, and execute the callback if we do. More...

void	handle_serialized_message (const std::shared_ptr< rclcpp::SerializedMessage > &serialized_message, const rclcpp::MessageInfo &message_info) override

void	handle_loaned_message (void *loaned_message, const rclcpp::MessageInfo &message_info) override

void	return_message (std::shared_ptr< void > &message) override
	Return the borrowed message. More...

void	return_serialized_message (std::shared_ptr< rclcpp::SerializedMessage > &message) override
	Return the borrowed serialized message. More...

bool	use_take_shared_method () const

rclcpp::dynamic_typesupport::DynamicMessageType::SharedPtr	get_shared_dynamic_message_type () override

rclcpp::dynamic_typesupport::DynamicMessage::SharedPtr	get_shared_dynamic_message () override

rclcpp::dynamic_typesupport::DynamicSerializationSupport::SharedPtr	get_shared_dynamic_serialization_support () override

rclcpp::dynamic_typesupport::DynamicMessage::SharedPtr	create_dynamic_message () override
	Borrow a new serialized message (this clones!) More...

void	return_dynamic_message (rclcpp::dynamic_typesupport::DynamicMessage::SharedPtr &message) override

void	handle_dynamic_message (const rclcpp::dynamic_typesupport::DynamicMessage::SharedPtr &message, const rclcpp::MessageInfo &message_info) override

Public Member Functions inherited from rclcpp::SubscriptionBase
RCLCPP_PUBLIC	SubscriptionBase (rclcpp::node_interfaces::NodeBaseInterface *node_base, const rosidl_message_type_support_t &type_support_handle, const std::string &topic_name, const rcl_subscription_options_t &subscription_options, const SubscriptionEventCallbacks &event_callbacks, bool use_default_callbacks, DeliveredMessageKind delivered_message_kind=DeliveredMessageKind::ROS_MESSAGE)
	Constructor. More...

virtual RCLCPP_PUBLIC	~SubscriptionBase ()
	Destructor.

RCLCPP_PUBLIC void	bind_event_callbacks (const SubscriptionEventCallbacks &event_callbacks, bool use_default_callbacks)
	Add event handlers for passed in event_callbacks.

RCLCPP_PUBLIC const char *	get_topic_name () const
	Get the topic that this subscription is subscribed on.

RCLCPP_PUBLIC std::shared_ptr< rcl_subscription_t >	get_subscription_handle ()

RCLCPP_PUBLIC std::shared_ptr< const rcl_subscription_t >	get_subscription_handle () const

RCLCPP_PUBLIC const std::unordered_map< rcl_subscription_event_type_t, std::shared_ptr< rclcpp::EventHandlerBase > > &	get_event_handlers () const
	Get all the QoS event handlers associated with this subscription. More...

RCLCPP_PUBLIC rclcpp::QoS	get_actual_qos () const
	Get the actual QoS settings, after the defaults have been determined. More...

RCLCPP_PUBLIC bool	take_type_erased (void *message_out, rclcpp::MessageInfo &message_info_out)
	Take the next inter-process message from the subscription as a type erased pointer. More...

RCLCPP_PUBLIC bool	take_serialized (rclcpp::SerializedMessage &message_out, rclcpp::MessageInfo &message_info_out)
	Take the next inter-process message, in its serialized form, from the subscription. More...

RCLCPP_PUBLIC const rosidl_message_type_support_t &	get_message_type_support_handle () const

RCLCPP_PUBLIC bool	is_serialized () const
	Return if the subscription is serialized. More...

RCLCPP_PUBLIC DeliveredMessageKind	get_delivered_message_kind () const
	Return the delivered message kind. More...

RCLCPP_PUBLIC size_t	get_publisher_count () const
	Get matching publisher count. More...

RCLCPP_PUBLIC bool	can_loan_messages () const
	Check if subscription instance can loan messages. More...

RCLCPP_PUBLIC void	setup_intra_process (uint64_t intra_process_subscription_id, IntraProcessManagerWeakPtr weak_ipm)
	Implemenation detail.

RCLCPP_PUBLIC rclcpp::Waitable::SharedPtr	get_intra_process_waitable () const
	Return the waitable for intra-process. More...

RCLCPP_PUBLIC bool	exchange_in_use_by_wait_set_state (void *pointer_to_subscription_part, bool in_use_state)
	Exchange state of whether or not a part of the subscription is used by a wait set. More...

RCLCPP_PUBLIC std::vector< rclcpp::NetworkFlowEndpoint >	get_network_flow_endpoints () const
	Get network flow endpoints. More...

void	set_on_new_message_callback (std::function< void(size_t)> callback)
	Set a callback to be called when each new message is received. More...

void	clear_on_new_message_callback ()
	Unset the callback registered for new messages, if any.

void	set_on_new_intra_process_message_callback (std::function< void(size_t)> callback)
	Set a callback to be called when each new intra-process message is received. More...

void	clear_on_new_intra_process_message_callback ()
	Unset the callback registered for new intra-process messages, if any.

void	set_on_new_qos_event_callback (std::function< void(size_t)> callback, rcl_subscription_event_type_t event_type)
	Set a callback to be called when each new qos event instance occurs. More...

void	clear_on_new_qos_event_callback (rcl_subscription_event_type_t event_type)
	Unset the callback registered for new qos events, if any.

RCLCPP_PUBLIC bool	is_cft_enabled () const
	Check if content filtered topic feature of the subscription instance is enabled. More...

RCLCPP_PUBLIC void	set_content_filter (const std::string &filter_expression, const std::vector< std::string > &expression_parameters={})
	Set the filter expression and expression parameters for the subscription. More...

RCLCPP_PUBLIC rclcpp::ContentFilterOptions	get_content_filter () const
	Get the filter expression and expression parameters for the subscription. More...

RCLCPP_PUBLIC bool	take_dynamic_message (rclcpp::dynamic_typesupport::DynamicMessage &message_out, rclcpp::MessageInfo &message_info_out)

Friends
class	rclcpp::node_interfaces::NodeTopicsInterface

Additional Inherited Members
Protected Member Functions inherited from rclcpp::SubscriptionBase
template<typename EventCallbackT >
void	add_event_handler (const EventCallbackT &callback, const rcl_subscription_event_type_t event_type)

RCLCPP_PUBLIC void	default_incompatible_qos_callback (QOSRequestedIncompatibleQoSInfo &info) const

RCLCPP_PUBLIC void	default_incompatible_type_callback (IncompatibleTypeInfo &info) const

RCLCPP_PUBLIC bool	matches_any_intra_process_publishers (const rmw_gid_t *sender_gid) const

RCLCPP_PUBLIC void	set_on_new_message_callback (rcl_event_callback_t callback, const void *user_data)

Protected Attributes inherited from rclcpp::SubscriptionBase
rclcpp::node_interfaces::NodeBaseInterface *const	node_base_

std::shared_ptr< rcl_node_t >	node_handle_

std::recursive_mutex	callback_mutex_

std::function< void(size_t)>	on_new_message_callback_ {nullptr}

std::shared_ptr< rcl_subscription_t >	subscription_handle_

std::shared_ptr< rcl_subscription_t >	intra_process_subscription_handle_

rclcpp::Logger	node_logger_

std::unordered_map< rcl_subscription_event_type_t, std::shared_ptr< rclcpp::EventHandlerBase > >	event_handlers_

bool	use_intra_process_

IntraProcessManagerWeakPtr	weak_ipm_

uint64_t	intra_process_subscription_id_

std::shared_ptr< rclcpp::experimental::SubscriptionIntraProcessBase >	subscription_intra_process_

const SubscriptionEventCallbacks	event_callbacks_

Detailed Description

template<typename MessageT, typename AllocatorT = std::allocator<void>, typename SubscribedT = typename rclcpp::TypeAdapter<MessageT>::custom_type, typename ROSMessageT = typename rclcpp::TypeAdapter<MessageT>::ros_message_type, typename MessageMemoryStrategyT = rclcpp::message_memory_strategy::MessageMemoryStrategy< ROSMessageT, AllocatorT >>
class rclcpp::Subscription< MessageT, AllocatorT, SubscribedT, ROSMessageT, MessageMemoryStrategyT >

Subscription implementation, templated on the type of message this subscription receives.

Definition at line 75 of file subscription.hpp.

Constructor & Destructor Documentation

◆ Subscription()

template<typename MessageT , typename AllocatorT = std::allocator<void>, typename SubscribedT = typename rclcpp::TypeAdapter<MessageT>::custom_type, typename ROSMessageT = typename rclcpp::TypeAdapter<MessageT>::ros_message_type, typename MessageMemoryStrategyT = rclcpp::message_memory_strategy::MessageMemoryStrategy< ROSMessageT, AllocatorT >>

rclcpp::Subscription< MessageT, AllocatorT, SubscribedT, ROSMessageT, MessageMemoryStrategyT >::Subscription	(	rclcpp::node_interfaces::NodeBaseInterface *	node_base,
		const rosidl_message_type_support_t &	type_support_handle,
		const std::string &	topic_name,
		const rclcpp::QoS &	qos,
		AnySubscriptionCallback< MessageT, AllocatorT >	callback,
		const rclcpp::SubscriptionOptionsWithAllocator< AllocatorT > &	options,
		typename MessageMemoryStrategyT::SharedPtr	message_memory_strategy,
		SubscriptionTopicStatisticsSharedPtr	subscription_topic_statistics = `nullptr`
	)

inline

Default constructor.

The constructor for a subscription is almost never called directly. Instead, subscriptions should be instantiated through the function rclcpp::create_subscription().

Parameters

[in]	node_base	NodeBaseInterface pointer that is used in part of the setup.
[in]	type_support_handle	rosidl type support struct, for the Message type of the topic.
[in]	topic_name	Name of the topic to subscribe to.
[in]	qos	QoS profile for Subcription.
[in]	callback	User defined callback to call when a message is received.
[in]	options	Options for the subscription.
[in]	message_memory_strategy	The memory strategy to be used for managing message memory.
[in]	subscription_topic_statistics	Optional pointer to a topic statistics subcription.

Exceptions

std::invalid_argument if the QoS is uncompatible with intra-process (if one of the following conditions are true: qos_profile.history == RMW_QOS_POLICY_HISTORY_KEEP_ALL, qos_profile.depth == 0 or qos_profile.durability != RMW_QOS_POLICY_DURABILITY_VOLATILE).

Definition at line 131 of file subscription.hpp.

References rclcpp::SubscriptionBase::get_actual_qos(), and rclcpp::SubscriptionBase::setup_intra_process().

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Member Function Documentation

◆ create_dynamic_message()

template<typename MessageT , typename AllocatorT = std::allocator<void>, typename SubscribedT = typename rclcpp::TypeAdapter<MessageT>::custom_type, typename ROSMessageT = typename rclcpp::TypeAdapter<MessageT>::ros_message_type, typename MessageMemoryStrategyT = rclcpp::message_memory_strategy::MessageMemoryStrategy< ROSMessageT, AllocatorT >>

rclcpp::dynamic_typesupport::DynamicMessage::SharedPtr rclcpp::Subscription< MessageT, AllocatorT, SubscribedT, ROSMessageT, MessageMemoryStrategyT >::create_dynamic_message ( )

inlineoverridevirtual

Borrow a new serialized message (this clones!)

Returns: Shared pointer to a rclcpp::dynamic_typesupport::DynamicMessage.

Implements rclcpp::SubscriptionBase.

Definition at line 429 of file subscription.hpp.

◆ create_message()

template<typename MessageT , typename AllocatorT = std::allocator<void>, typename SubscribedT = typename rclcpp::TypeAdapter<MessageT>::custom_type, typename ROSMessageT = typename rclcpp::TypeAdapter<MessageT>::ros_message_type, typename MessageMemoryStrategyT = rclcpp::message_memory_strategy::MessageMemoryStrategy< ROSMessageT, AllocatorT >>

std::shared_ptr<void> rclcpp::Subscription< MessageT, AllocatorT, SubscribedT, ROSMessageT, MessageMemoryStrategyT >::create_message ( )

inlineoverridevirtual

Borrow a new message.

Returns: Shared pointer to the fresh message.

Implements rclcpp::SubscriptionBase.

Definition at line 281 of file subscription.hpp.

◆ create_serialized_message()

template<typename MessageT , typename AllocatorT = std::allocator<void>, typename SubscribedT = typename rclcpp::TypeAdapter<MessageT>::custom_type, typename ROSMessageT = typename rclcpp::TypeAdapter<MessageT>::ros_message_type, typename MessageMemoryStrategyT = rclcpp::message_memory_strategy::MessageMemoryStrategy< ROSMessageT, AllocatorT >>

std::shared_ptr<rclcpp::SerializedMessage> rclcpp::Subscription< MessageT, AllocatorT, SubscribedT, ROSMessageT, MessageMemoryStrategyT >::create_serialized_message ( )

inlineoverridevirtual

Borrow a new serialized message.

Returns: Shared pointer to a rcl_message_serialized_t.

Implements rclcpp::SubscriptionBase.

Definition at line 291 of file subscription.hpp.

◆ handle_message()

template<typename MessageT , typename AllocatorT = std::allocator<void>, typename SubscribedT = typename rclcpp::TypeAdapter<MessageT>::custom_type, typename ROSMessageT = typename rclcpp::TypeAdapter<MessageT>::ros_message_type, typename MessageMemoryStrategyT = rclcpp::message_memory_strategy::MessageMemoryStrategy< ROSMessageT, AllocatorT >>

void rclcpp::Subscription< MessageT, AllocatorT, SubscribedT, ROSMessageT, MessageMemoryStrategyT >::handle_message	(	std::shared_ptr< void > &	message,
		const rclcpp::MessageInfo &	message_info
	)

inlineoverridevirtual

Check if we need to handle the message, and execute the callback if we do.

Parameters

[in]	message	Shared pointer to the message to handle.
[in]	message_info	Metadata associated with this message.

Implements rclcpp::SubscriptionBase.

Definition at line 297 of file subscription.hpp.

References rclcpp::MessageInfo::get_rmw_message_info().

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◆ return_message()

template<typename MessageT , typename AllocatorT = std::allocator<void>, typename SubscribedT = typename rclcpp::TypeAdapter<MessageT>::custom_type, typename ROSMessageT = typename rclcpp::TypeAdapter<MessageT>::ros_message_type, typename MessageMemoryStrategyT = rclcpp::message_memory_strategy::MessageMemoryStrategy< ROSMessageT, AllocatorT >>

void rclcpp::Subscription< MessageT, AllocatorT, SubscribedT, ROSMessageT, MessageMemoryStrategyT >::return_message ( std::shared_ptr< void > & message )

inlineoverridevirtual

Return the borrowed message.

Parameters

[in,out] message message to be returned

Implements rclcpp::SubscriptionBase.

Definition at line 382 of file subscription.hpp.

◆ return_serialized_message()

template<typename MessageT , typename AllocatorT = std::allocator<void>, typename SubscribedT = typename rclcpp::TypeAdapter<MessageT>::custom_type, typename ROSMessageT = typename rclcpp::TypeAdapter<MessageT>::ros_message_type, typename MessageMemoryStrategyT = rclcpp::message_memory_strategy::MessageMemoryStrategy< ROSMessageT, AllocatorT >>

void rclcpp::Subscription< MessageT, AllocatorT, SubscribedT, ROSMessageT, MessageMemoryStrategyT >::return_serialized_message ( std::shared_ptr< rclcpp::SerializedMessage > & message )

inlineoverridevirtual

Return the borrowed serialized message.

Parameters

[in,out] message serialized message to be returned

Implements rclcpp::SubscriptionBase.

Definition at line 393 of file subscription.hpp.

◆ take() [1/2]

template<typename MessageT , typename AllocatorT = std::allocator<void>, typename SubscribedT = typename rclcpp::TypeAdapter<MessageT>::custom_type, typename ROSMessageT = typename rclcpp::TypeAdapter<MessageT>::ros_message_type, typename MessageMemoryStrategyT = rclcpp::message_memory_strategy::MessageMemoryStrategy< ROSMessageT, AllocatorT >>

bool rclcpp::Subscription< MessageT, AllocatorT, SubscribedT, ROSMessageT, MessageMemoryStrategyT >::take	(	ROSMessageType &	message_out,
		rclcpp::MessageInfo &	message_info_out
	)

inline

Take the next message from the inter-process subscription.

Data may be taken (written) into the message_out and message_info_out even if false is returned. Specifically in the case of dropping redundant intra-process data, where data is received via both intra-process and inter-process (due to the underlying middleware being unabled to avoid this duplicate delivery) and so inter-process data from those intra-process publishers is ignored, but it has to be taken to know if it came from an intra-process publisher or not, and therefore could be dropped.

See also: SubscriptionBase::take_type_erased()

Parameters

[out]	message_out	The message into which take will copy the data.
[out]	message_info_out	The message info for the taken message.

Returns: true if data was taken and is valid, otherwise false

Exceptions

any	rcl errors from rcl_take,

See also: rclcpp::exceptions::throw_from_rcl_error()

Definition at line 252 of file subscription.hpp.

References rclcpp::SubscriptionBase::take_type_erased().

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◆ take() [2/2]

template<typename MessageT , typename AllocatorT = std::allocator<void>, typename SubscribedT = typename rclcpp::TypeAdapter<MessageT>::custom_type, typename ROSMessageT = typename rclcpp::TypeAdapter<MessageT>::ros_message_type, typename MessageMemoryStrategyT = rclcpp::message_memory_strategy::MessageMemoryStrategy< ROSMessageT, AllocatorT >>

template<typename TakeT >

std::enable_if_t< !rosidl_generator_traits::is_message<TakeT>::value && std::is_same_v<TakeT, SubscribedType>, bool > rclcpp::Subscription< MessageT, AllocatorT, SubscribedT, ROSMessageT, MessageMemoryStrategyT >::take	(	TakeT &	message_out,
		rclcpp::MessageInfo &	message_info_out
	)

inline

Take the next message from the inter-process subscription.

This version takes a SubscribedType which is different from the ROSMessageType when a rclcpp::TypeAdapter is in used.

See also: take(ROSMessageType &, rclcpp::MessageInfo &)

Definition at line 270 of file subscription.hpp.

References rclcpp::SubscriptionBase::take_type_erased().

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

rclcpp/include/rclcpp/subscription.hpp

Public Types

Public Member Functions

Friends

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ Subscription()

Member Function Documentation

◆ create_dynamic_message()

◆ create_message()

◆ create_serialized_message()

◆ handle_message()

◆ return_message()

◆ return_serialized_message()

◆ take() [1/2]

◆ take() [2/2]