RosPublisherNode< MessageT > Class Template Reference

Generic behavior tree node wrapper for a ROS 2 publisher. More...

#include <auto_apms_behavior_tree_core/node/ros_publisher_node.hpp>

Public Member Functions
	RosPublisherNode (const std::string &instance_name, const Config &config, Context context, const rclcpp::QoS &qos={10})
	Constructor.
virtual bool	setMessage (MessageT &msg)
	Callback invoked when ticked to define the message to be published.
bool	createPublisher (const std::string &topic_name)
	Create the ROS 2 publisher.
std::string	getTopicName () const
	Get the name of the topic name this node publishes to.

Static Public Member Functions
static BT::PortsList	providedBasicPorts (BT::PortsList addition)
	Derived nodes implementing the static method RosPublisherNode::providedPorts may call this method to also include the default port for ROS 2 behavior tree nodes.
static BT::PortsList	providedPorts ()
	If a behavior tree requires input/output data ports, the developer must define this method accordingly.

Detailed Description

template<class MessageT>
class auto_apms_behavior_tree::core::RosPublisherNode< MessageT >

Generic behavior tree node wrapper for a ROS 2 publisher.

When ticked, this node publishes a single message to a topic. Inheriting classes must reimplement the virtual methods as described below.

By default, the name of the topic will be determined as follows:

1. If a value is passed using the input port named topic, use that.
2. Otherwise, use the value from NodeRegistrationOptions::topic passed on construction as part of RosNodeContext.

It is possible to customize which data port is used to determine the topic name and also extend the input's value with a prefix or suffix. This is achieved by including the special pattern (input:<port_name>) in NodeRegistrationOptions::topic and replacing <port_name> with the desired input port name.

Example: Given the user implements an input port BT::InputPort<std::string>("my_port"), one may create a client for the topic "foo/bar" by defining NodeRegistrationOptions::topic as (input:my_port)/bar and providing the string "foo" to the port with name my_port.

Additionally, the following characteristics depend on NodeRegistrationOptions:

• wait_timeout: Period [s] (measured since tree construction) after the we abort waiting for a subscriber.
• allow_unreachable: Flag whether to tolerate when no subscriber is connected. If set to true, a warning is logged. Otherwise, an exception is raised.
• logger_level: Minimum severity level enabled for logging using the ROS 2 Logger API.

Template Parameters

MessageT

Type of the ROS 2 message.

Definition at line 63 of file ros_publisher_node.hpp.

Constructor & Destructor Documentation

RosPublisherNode()

template<class MessageT>

RosPublisherNode ( const std::string & instance_name, const Config & config, Context context, const rclcpp::QoS & qos = {10} )

inlineexplicit

Constructor.

Derived nodes are automatically created by TreeBuilder::instantiate when included inside a node manifest associated with the behavior tree resource.

Parameters

instance_name	Name given to this specific node instance.
config	Structure of internal data determined at runtime by BT::BehaviorTreeFactory.
context	Additional parameters specific to ROS 2 determined at runtime by TreeBuilder.
qos	Quality of service settings forwarded to the publisher.

Definition at line 150 of file ros_publisher_node.hpp.

Member Function Documentation

providedBasicPorts()

template<class MessageT>

static BT::PortsList providedBasicPorts ( BT::PortsList addition )

inlinestatic

Derived nodes implementing the static method RosPublisherNode::providedPorts may call this method to also include the default port for ROS 2 behavior tree nodes.

Parameters

addition

Additional ports to add to the ports list.

Returns

List of ports containing the default port along with node-specific ports.

Definition at line 94 of file ros_publisher_node.hpp.

providedPorts()

template<class MessageT>

static BT::PortsList providedPorts ( )

inlinestatic

If a behavior tree requires input/output data ports, the developer must define this method accordingly.

Returns

List of ports used by this node.

Definition at line 105 of file ros_publisher_node.hpp.

setMessage()

template<class MessageT>

bool setMessage ( MessageT & msg )

inlinevirtual

Callback invoked when ticked to define the message to be published.

The node may deny to publish a message by returning false. Otherwise, this method should return true.

By default, this callback simply returns true and sends an empty message.

Parameters

msg	Reference to the message.

Returns

false if no message should be published. In that case, the return status of this node will be BT::NodeStatus::FAILURE. Otherwise, the message will be published and the node returns BT::NodeStatus::SUCCESS.

Definition at line 271 of file ros_publisher_node.hpp.

createPublisher()

template<class MessageT>

bool createPublisher ( const std::string & topic_name )

inline

Create the ROS 2 publisher.

Parameters

topic_name

Name of the topic.

Returns

true if the publisher was created successfully, false otherwise.

Definition at line 171 of file ros_publisher_node.hpp.

getTopicName()

template<class MessageT>

std::string getTopicName ( ) const

inline

Get the name of the topic name this node publishes to.

Returns

String representing the topic name.

Definition at line 277 of file ros_publisher_node.hpp.

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

• auto_apms_behavior_tree_core/include/auto_apms_behavior_tree_core/node/ros_publisher_node.hpp