A wrapper for rclcpp_lifecycle::LifecycleNode to simplify application composition through unified component interfaces while supporting lifecycle states and transitions. More...

#include <LifecycleComponent.hpp>

Inheritance diagram for modulo_components::LifecycleComponent:

Public Member Functions
	LifecycleComponent (const rclcpp::NodeOptions &node_options, const std::string &fallback_name="LifecycleComponent")
	Constructor from node options.

virtual	~LifecycleComponent ()=default
	Virtual default destructor.

Public Member Functions inherited from modulo_components::ComponentInterface
virtual	~ComponentInterface ()
	Virtual destructor.

template<>
double	get_period () const

template<>
std::chrono::nanoseconds	get_period () const

template<>
rclcpp::Duration	get_period () const

Protected Member Functions
std::shared_ptr< state_representation::ParameterInterface >	get_parameter (const std::string &name) const
	Get a parameter by name.

virtual bool	on_configure_callback ()
	Steps to execute when configuring the component.

virtual bool	on_cleanup_callback ()
	Steps to execute when cleaning up the component.

virtual bool	on_activate_callback ()
	Steps to execute when activating the component.

virtual bool	on_deactivate_callback ()
	Steps to execute when deactivating the component.

virtual bool	on_shutdown_callback ()
	Steps to execute when shutting down the component.

virtual bool	on_error_callback ()
	Steps to execute when handling errors.

template<typename DataT >
void	add_output (const std::string &signal_name, const std::shared_ptr< DataT > &data, const std::string &default_topic="", bool fixed_topic=false, bool publish_on_step=true)
	Add an output signal of the component.

rclcpp_lifecycle::State	get_lifecycle_state () const
	Get the current lifecycle state of the component.

Protected Member Functions inherited from modulo_components::ComponentInterface
	ComponentInterface (const std::shared_ptr< rclcpp::node_interfaces::NodeInterfaces< ALL_RCLCPP_NODE_INTERFACES > > &interfaces)
	Constructor with all node interfaces.

double	get_rate () const
	Get the component rate in Hertz.

template<typename T >
T	get_period () const
	Get the component period.

virtual void	on_step_callback ()
	Steps to execute periodically. To be redefined by derived Component classes.

void	add_parameter (const std::shared_ptr< state_representation::ParameterInterface > &parameter, const std::string &description, bool read_only=false)
	Add a parameter.

template<typename T >
void	add_parameter (const std::string &name, const T &value, const std::string &description, bool read_only=false)
	Add a parameter.

std::shared_ptr< state_representation::ParameterInterface >	get_parameter (const std::string &name) const
	Get a parameter by name.

template<typename T >
T	get_parameter_value (const std::string &name) const
	Get a parameter value by name.

template<typename T >
void	set_parameter_value (const std::string &name, const T &value)
	Set the value of a parameter.

virtual bool	on_validate_parameter_callback (const std::shared_ptr< state_representation::ParameterInterface > &parameter)
	Parameter validation function to be redefined by derived Component classes.

void	add_predicate (const std::string &predicate_name, bool predicate_value)
	Add a predicate to the map of predicates.

void	add_predicate (const std::string &predicate_name, const std::function< bool(void)> &predicate_function)
	Add a predicate to the map of predicates based on a function to periodically call.

bool	get_predicate (const std::string &predicate_name) const
	Get the logical value of a predicate.

void	set_predicate (const std::string &predicate_name, bool predicate_value)
	Set the value of the predicate given as parameter, if the predicate is not found does not do anything.

void	set_predicate (const std::string &predicate_name, const std::function< bool(void)> &predicate_function)
	Set the value of the predicate given as parameter, if the predicate is not found does not do anything.

void	add_trigger (const std::string &trigger_name)
	Add a trigger to the component. Triggers are predicates that are always false except when it's triggered in which case it is set back to false immediately after it is read.

void	trigger (const std::string &trigger_name)
	Latch the trigger with the provided name.

void	declare_input (const std::string &signal_name, const std::string &default_topic="", bool fixed_topic=false)
	Declare an input to create the topic parameter without adding it to the map of inputs yet.

void	declare_output (const std::string &signal_name, const std::string &default_topic="", bool fixed_topic=false)
	Declare an output to create the topic parameter without adding it to the map of outputs yet.

template<typename DataT >
void	add_input (const std::string &signal_name, const std::shared_ptr< DataT > &data, const std::string &default_topic="", bool fixed_topic=false)
	Add and configure an input signal of the component.

template<typename DataT >
void	add_input (const std::string &signal_name, const std::shared_ptr< DataT > &data, const std::function< void()> &callback, const std::string &default_topic="", bool fixed_topic=false)
	Add and configure an input signal of the component.

template<typename MsgT >
void	add_input (const std::string &signal_name, const std::function< void(const std::shared_ptr< MsgT >)> &callback, const std::string &default_topic="", bool fixed_topic=false)
	Add and configure an input signal of the component.

template<typename DataT >
std::string	create_output (modulo_core::communication::PublisherType publisher_type, const std::string &signal_name, const std::shared_ptr< DataT > &data, const std::string &default_topic, bool fixed_topic, bool publish_on_step)
	Helper function to parse the signal name and add an unconfigured PublisherInterface to the map of outputs.

void	publish_output (const std::string &signal_name)
	Trigger the publishing of an output.

void	remove_input (const std::string &signal_name)
	Remove an input from the map of inputs.

void	remove_output (const std::string &signal_name)
	Remove an output from the map of outputs.

void	add_service (const std::string &service_name, const std::function< ComponentServiceResponse(void)> &callback)
	Add a service to trigger a callback function with no input arguments.

void	add_service (const std::string &service_name, const std::function< ComponentServiceResponse(const std::string &string)> &callback)
	Add a service to trigger a callback function with a string payload.

void	add_periodic_callback (const std::string &name, const std::function< void(void)> &callback)
	Add a periodic callback function.

void	add_tf_broadcaster ()
	Configure a transform broadcaster.

void	add_static_tf_broadcaster ()
	Configure a static transform broadcaster.

void	add_tf_listener ()
	Configure a transform buffer and listener.

void	send_transform (const state_representation::CartesianPose &transform)
	Send a transform to TF.

void	send_transforms (const std::vector< state_representation::CartesianPose > &transforms)
	Send a vector of transforms to TF.

void	send_static_transform (const state_representation::CartesianPose &transform)
	Send a static transform to TF.

void	send_static_transforms (const std::vector< state_representation::CartesianPose > &transforms)
	Send a vector of static transforms to TF.

state_representation::CartesianPose	lookup_transform (const std::string &frame, const std::string &reference_frame, const tf2::TimePoint &time_point, const tf2::Duration &duration)
	Look up a transform from TF.

state_representation::CartesianPose	lookup_transform (const std::string &frame, const std::string &reference_frame="world", double validity_period=-1.0, const tf2::Duration &duration=tf2::Duration(std::chrono::microseconds(10)))
	Look up a transform from TF.

rclcpp::QoS	get_qos () const
	Getter of the Quality of Service attribute.

void	set_qos (const rclcpp::QoS &qos)
	Set the Quality of Service for ROS publishers and subscribers.

virtual void	raise_error ()
	Put the component in error state by setting the 'in_error_state' predicate to true.

void	publish_predicates ()
	Helper function to publish all predicates.

void	publish_outputs ()
	Helper function to publish all output signals.

void	evaluate_periodic_callbacks ()
	Helper function to evaluate all periodic function callbacks.

Friends
class	LifecycleComponentPublicInterface

Additional Inherited Members
Protected Attributes inherited from modulo_components::ComponentInterface
std::map< std::string, std::shared_ptr< modulo_core::communication::SubscriptionInterface > >	inputs_
	Map of inputs.

std::map< std::string, std::shared_ptr< modulo_core::communication::PublisherInterface > >	outputs_
	Map of outputs.

std::map< std::string, bool >	periodic_outputs_
	Map of outputs with periodic publishing flag.

Detailed Description

A wrapper for rclcpp_lifecycle::LifecycleNode to simplify application composition through unified component interfaces while supporting lifecycle states and transitions.

This class is intended for direct inheritance to implement custom state-based components that perform different behaviors based on their state and on state transitions. An example of state-based behaviour is a signal component that requires configuration steps to determine which inputs to register and subsequently should publish outputs only when the component is activated. Developers should override on_validate_parameter_callback() if any parameters are added. In addition, the following state transition callbacks should be overridden whenever custom transition behavior is needed:

Definition at line 29 of file LifecycleComponent.hpp.

Constructor & Destructor Documentation

◆ LifecycleComponent()

modulo_components::LifecycleComponent::LifecycleComponent	(	const rclcpp::NodeOptions &	node_options,
		const std::string &	fallback_name = `"LifecycleComponent"`
	)

explicit

Constructor from node options.

Parameters

node_options	Node options as used in ROS2 LifecycleNode
fallback_name	The name of the component if it was not provided through the node options

Definition at line 8 of file LifecycleComponent.cpp.

Member Function Documentation

◆ add_output()

template<typename DataT >

void modulo_components::LifecycleComponent::add_output	(	const std::string &	signal_name,
		const std::shared_ptr< DataT > &	data,
		const std::string &	default_topic = `""`,
		bool	fixed_topic = `false`,
		bool	publish_on_step = `true`
	)

inlineprotected

Add an output signal of the component.

Template Parameters

DataT Type of the data pointer

Parameters

signal_name	Name of the output signal
data	Data to transmit on the output signal
default_topic	If set, the default value for the topic name to use
fixed_topic	If true, the topic name of the output signal is fixed
publish_on_step	If true, the output is published periodically on step

Definition at line 284 of file LifecycleComponent.hpp.

◆ get_lifecycle_state()

rclcpp_lifecycle::State modulo_components::LifecycleComponent::get_lifecycle_state ( ) const

protected

Get the current lifecycle state of the component.

Definition at line 343 of file LifecycleComponent.cpp.

◆ get_parameter()

std::shared_ptr< state_representation::ParameterInterface > modulo_components::LifecycleComponent::get_parameter ( const std::string & name ) const

protected

Get a parameter by name.

Parameters

name	The name of the parameter

Exceptions

modulo_core::exceptions::ParameterException if the parameter could not be found

Returns: The ParameterInterface pointer to a Parameter instance

Definition at line 19 of file LifecycleComponent.cpp.

◆ on_activate_callback()

bool modulo_components::LifecycleComponent::on_activate_callback ( )

protectedvirtual

Steps to execute when activating the component.

This method can be overridden by derived Component classes. Activation generally involves final setup steps before the on_step callback is periodically evaluated.

Returns: True if activation is successful, false otherwise

Definition at line 131 of file LifecycleComponent.cpp.

◆ on_cleanup_callback()

bool modulo_components::LifecycleComponent::on_cleanup_callback ( )

protectedvirtual

Steps to execute when cleaning up the component.

This method can be overridden by derived Component classes. Cleanup generally involves resetting the properties and states to initial conditions.

Returns: True if cleanup is successful, false otherwise

Definition at line 96 of file LifecycleComponent.cpp.

◆ on_configure_callback()

bool modulo_components::LifecycleComponent::on_configure_callback ( )

protectedvirtual

Steps to execute when configuring the component.

This method can be overridden by derived Component classes. Configuration generally involves reading parameters and adding inputs and outputs.

Returns: True if configuration is successful, false otherwise

Definition at line 70 of file LifecycleComponent.cpp.

◆ on_deactivate_callback()

bool modulo_components::LifecycleComponent::on_deactivate_callback ( )

protectedvirtual

Steps to execute when deactivating the component.

This method can be overridden by derived Component classes. Deactivation generally involves any steps to reset the component to an inactive state.

Returns: True if deactivation is successful, false otherwise

Definition at line 158 of file LifecycleComponent.cpp.

◆ on_error_callback()

bool modulo_components::LifecycleComponent::on_error_callback ( )

protectedvirtual

Steps to execute when handling errors.

This method can be overridden by derived Component classes. Error handling generally involves recovering and resetting the component to an unconfigured state.

Returns: True if error handling is successful, false otherwise

Definition at line 235 of file LifecycleComponent.cpp.

◆ on_shutdown_callback()

bool modulo_components::LifecycleComponent::on_shutdown_callback ( )

protectedvirtual

Steps to execute when shutting down the component.

This method can be overridden by derived Component classes. Shutdown generally involves the destruction of any threads or properties not handled by the base class.

Returns: True if shutdown is successful, false otherwise

Definition at line 208 of file LifecycleComponent.cpp.

Friends And Related Symbol Documentation

◆ LifecycleComponentPublicInterface

friend class LifecycleComponentPublicInterface

friend

Definition at line 31 of file LifecycleComponent.hpp.

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

/github/workspace/source/modulo_components/include/modulo_components/LifecycleComponent.hpp
/github/workspace/source/modulo_components/src/LifecycleComponent.cpp

Public Member Functions

Protected Member Functions

Friends

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ LifecycleComponent()

Member Function Documentation

◆ add_output()

◆ get_lifecycle_state()

◆ get_parameter()

◆ on_activate_callback()

◆ on_cleanup_callback()

◆ on_configure_callback()

◆ on_deactivate_callback()

◆ on_error_callback()

◆ on_shutdown_callback()

Friends And Related Symbol Documentation

◆ LifecycleComponentPublicInterface