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composition package from demos repo

action_tutorials_cpp action_tutorials_interfaces action_tutorials_py composition demo_nodes_cpp demo_nodes_cpp_native demo_nodes_py dummy_map_server dummy_robot_bringup dummy_sensors image_tools intra_process_demo lifecycle lifecycle_py logging_demo pendulum_control pendulum_msgs quality_of_service_demo_cpp quality_of_service_demo_py topic_monitor topic_statistics_demo

API Docs
Browse Code

Package Summary

Tags No category tags.
Version 0.20.5
License Apache License 2.0
Build type AMENT_CMAKE
Use RECOMMENDED

Repository Summary

Checkout URI https://github.com/ros2/demos.git
VCS Type git
VCS Version humble
Last Updated 2024-07-26
Dev Status DEVELOPED
CI status No Continuous Integration
Released RELEASED
Tags No category tags.
Contributing Help Wanted (0)
Good First Issues (0)
Pull Requests to Review (0)

Package Description

Examples for composing multiple nodes in a single process.

Additional Links

No additional links.

Maintainers

  • Audrow Nash
  • Michael Jeronimo

Authors

  • Dirk Thomas
  • Mabel Zhang
composition/README.md

What Is This?

This demo provides examples of three different ways to use the rclcpp_components API to compose multiple nodes in a single process.

This ROS 2 package consists of the following demo applications:

  1. dlopen_composition
  2. linktime_composition
  3. manual_composition

Build

Run the commands below to build the ROS 2 package:

colcon build --packages-up-to composition

Run

Manual Composition

Running manual_composition compiles an executable that runs the following 4 components:

  • Talker: A ROS 2 component that publishes a string
  • Listener: A ROS 2 component that prints the received string from Talker
  • Server: A ROS 2 component that adds two integers and outputs its result to Client
  • Client: A ROS 2 component that sends two integers to Server and prints the received result from Server 
ros2 run composition manual_composition

DlOpen Composition

This runs dlopen_composition which is an alternative to run-time composition by creating a generic container process and explicitly passing the libraries to load without using ROS interfaces.

The process will open each library and create one instance of each “rclcpp::Node” class in the library.

ros2 run composition dlopen_composition `ros2 pkg prefix composition`/lib/libtalker_component.so `ros2 pkg prefix composition`/lib/liblistener_component.so

Linktime Composition

Similar to previous, this runs linktime_composition which links all classes from libraries that are registered under the library_path with the linker.

ros2 run composition linktime_composition

Composition Using Launch Actions

Rather than using the command line tool to run each composition, we can automate this action with ros2 launch functionality:

ros2 launch composition composition_demo.launch.py

Verify

Manual Composition

When executed correctly, strings should be printed to terminal similar to what is shown below:

[INFO] [1674528188.026468320] [talker]: Publishing: 'Hello World: 1'
[INFO] [1674528188.027043857] [listener]: I heard: [Hello World: 1]
[INFO] [1674528189.026414368] [talker]: Publishing: 'Hello World: 2'
[INFO] [1674528189.026742015] [listener]: I heard: [Hello World: 2]
[INFO] [1674528189.032512995] [Server]: Incoming request: [a: 2, b: 3]
[INFO] [1674528189.032815843] [Client]: Got result: [5]
[INFO] [1674528190.026455807] [talker]: Publishing: 'Hello World: 3'
[INFO] [1674528190.026795770] [listener]: I heard: [Hello World: 3]
[INFO] [1674528191.026457639] [talker]: Publishing: 'Hello World: 4'
[INFO] [1674528191.026801926] [listener]: I heard: [Hello World: 4]
[INFO] [1674528191.032377264] [Server]: Incoming request: [a: 2, b: 3]
[INFO] [1674528191.032604427] [Client]: Got result: [5]
[INFO] [1674528192.026428269] [talker]: Publishing: 'Hello World: 5'
[INFO] [1674528192.026537974] [listener]: I heard: [Hello World: 5]
[INFO] [1674528193.026437034] [talker]: Publishing: 'Hello World: 6'
[INFO] [1674528193.026767708] [listener]: I heard: [Hello World: 6]
[INFO] [1674528193.032377748] [Server]: Incoming request: [a: 2, b: 3]
[INFO] [1674528193.032603036] [Client]: Got result: [5]
#...

:warning:

Note that manually-composed components will not be reflected in the ros2 component list command line tool output.

DlOpen Composition

When executed correctly, strings should be printed to terminal similar to what is shown below:

INFO] [1674529118.496557668] [dlopen_composition]: Load library /opt/ros/humble/lib/libtalker_component.so
[INFO] [1674529118.496774575] [dlopen_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Talker>
[INFO] [1674529118.503388909] [dlopen_composition]: Load library /opt/ros/humble/lib/liblistener_component.so
[INFO] [1674529118.503739855] [dlopen_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Listener>
[INFO] [1674529119.503505873] [talker]: Publishing: 'Hello World: 1'
[INFO] [1674529119.503770137] [listener]: I heard: [Hello World: 1]
[INFO] [1674529120.503572362] [talker]: Publishing: 'Hello World: 2'
[INFO] [1674529120.503888374] [listener]: I heard: [Hello World: 2]
[INFO] [1674529121.503503459] [talker]: Publishing: 'Hello World: 3'
[INFO] [1674529121.503628269] [listener]: I heard: [Hello World: 3]
[INFO] [1674529122.503557862] [talker]: Publishing: 'Hello World: 4'
[INFO] [1674529122.503894772] [listener]: I heard: [Hello World: 4]
[INFO] [1674529123.503574524] [talker]: Publishing: 'Hello World: 5'
[INFO] [1674529123.503884894] [listener]: I heard: [Hello World: 5]
#...

:warning:

Note that dlopen-composed components will not be reflected in the ros2 component list command line tool output.

Linktime Composition

When executed correctly, strings should be printed to terminal similar to what is shown below:

[INFO] [1674528568.091949637] [linktime_composition]: Load library
[INFO] [1674528568.091995119] [linktime_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Client>
[INFO] [1674528568.098833910] [linktime_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Listener>
[INFO] [1674528568.100669644] [linktime_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Server>
[INFO] [1674528568.102665704] [linktime_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Talker>
[INFO] [1674528569.104717098] [talker]: Publishing: 'Hello World: 1'
[INFO] [1674528569.105206993] [listener]: I heard: [Hello World: 1]
[INFO] [1674528570.099206827] [Server]: Incoming request: [a: 2, b: 3]
[INFO] [1674528570.099376432] [Client]: Got result: [5]
[INFO] [1674528570.104656875] [talker]: Publishing: 'Hello World: 2'
[INFO] [1674528570.105069514] [listener]: I heard: [Hello World: 2]
[INFO] [1674528571.104710545] [talker]: Publishing: 'Hello World: 3'
[INFO] [1674528571.105150094] [listener]: I heard: [Hello World: 3]
[INFO] [1674528572.099350955] [Server]: Incoming request: [a: 2, b: 3]
[INFO] [1674528572.099628903] [Client]: Got result: [5]
[INFO] [1674528572.104631322] [talker]: Publishing: 'Hello World: 4'
[INFO] [1674528572.104911174] [listener]: I heard: [Hello World: 4]
[INFO] [1674528573.104596009] [talker]: Publishing: 'Hello World: 5'
[INFO] [1674528573.104751214] [listener]: I heard: [Hello World: 5]
#...

:warning:

Note that linktime-composed components will not be reflected in the ros2 component list command line tool output.

Composition Using Launch Actions

When executed correctly, strings should be printed to terminal similar to what is shown below:

[INFO] [launch]: All log files can be found below /root/.ros/log/2024-05-04-23-37-06-363020-d8ff93e471d7-9387
[INFO] [launch]: Default logging verbosity is set to INFO
[INFO] [component_container-1]: process started with pid [9402]
[component_container-1] [INFO] [1714865826.695090046] [my_container]: Load Library: /opt/ros/jazzy/lib/libtalker_component.so
[component_container-1] [INFO] [1714865826.696388047] [my_container]: Found class: rclcpp_components::NodeFactoryTemplate<composition::Talker>
[component_container-1] [INFO] [1714865826.696435882] [my_container]: Instantiate class: rclcpp_components::NodeFactoryTemplate<composition::Talker>
[INFO] [launch_ros.actions.load_composable_nodes]: Loaded node '/talker' in container '/my_container'
[component_container-1] [INFO] [1714865826.702958710] [my_container]: Load Library: /opt/ros/jazzy/lib/liblistener_component.so
[component_container-1] [INFO] [1714865826.703401061] [my_container]: Found class: rclcpp_components::NodeFactoryTemplate<composition::Listener>
[component_container-1] [INFO] [1714865826.703414344] [my_container]: Instantiate class: rclcpp_components::NodeFactoryTemplate<composition::Listener>
[INFO] [launch_ros.actions.load_composable_nodes]: Loaded node '/listener' in container '/my_container'
[component_container-1] [INFO] [1714865827.701941449] [talker]: Publishing: 'Hello World: 1'
[component_container-1] [INFO] [1714865827.702047599] [listener]: I heard: [Hello World: 1]
[component_container-1] [INFO] [1714865828.701984118] [talker]: Publishing: 'Hello World: 2'
[component_container-1] [INFO] [1714865828.702154523] [listener]: I heard: [Hello World: 2]
[component_container-1] [INFO] [1714865829.702004471] [talker]: Publishing: 'Hello World: 3'
[component_container-1] [INFO] [1714865829.702176059] [listener]: I heard: [Hello World: 3]
[component_container-1] [INFO] [1714865830.701876733] [talker]: Publishing: 'Hello World: 4'
[component_container-1] [INFO] [1714865830.701965546] [listener]: I heard: [Hello World: 4]
[component_container-1] [INFO] [1714865831.701885355] [talker]: Publishing: 'Hello World: 5'
[component_container-1] [INFO] [1714865831.701984823] [listener]: I heard: [Hello World: 5]

FAQ

Q: Why use node composition?

A: Node composition avoids the overhead of marshalling and unmarshaling messages by allowing nodes to be instantiated within the same process.

References

  1. Composing multiple nodes in a single process
  2. About Composition
CHANGELOG

Changelog for package composition

0.20.5 (2024-07-26)

0.20.4 (2024-05-15)

  • [composition] add launch action console output in the verify section (#677) (#682)
  • Contributors: mergify[bot]

0.20.3 (2023-01-10)

0.20.2 (2022-05-10)

0.20.1 (2022-04-08)

0.20.0 (2022-03-01)

0.19.0 (2022-01-14)

0.18.0 (2021-12-17)

  • Update maintainers to Audrow Nash and Michael Jeronimo (#543)
  • Additional fixes for documentation in demos. (#538)
  • Contributors: Audrow Nash, Chris Lalancette

0.17.0 (2021-10-18)

  • Fixing deprecated subscriber callback warnings (#532)
  • Contributors: Abrar Rahman Protyasha

0.16.0 (2021-08-11)

0.15.0 (2021-05-14)

0.14.2 (2021-04-26)

0.14.1 (2021-04-19)

0.14.0 (2021-04-06)

0.13.0 (2021-03-25)

0.12.1 (2021-03-18)

0.12.0 (2021-01-25)

  • Fix leak(#480) (#481)
  • Contributors: y-okumura-isp

0.11.0 (2020-12-10)

  • Update the package.xml files with the latest Open Robotics maintainers (#466)
  • Contributors: Michael Jeronimo

0.10.1 (2020-09-21)

0.10.0 (2020-06-17)

0.9.3 (2020-06-01)

0.9.2 (2020-05-26)

0.9.1 (2020-05-12)

0.9.0 (2020-04-30)

  • Replace deprecated launch_ros usage (#437)
  • Update launch_ros action usage (#431)
  • code style only: wrap after open parenthesis if not in one line (#429)
  • Contributors: Dirk Thomas, Jacob Perron

0.8.4 (2019-11-19)

0.8.3 (2019-11-11)

0.8.2 (2019-11-08)

0.8.1 (2019-10-23)

  • Replace ready_fn with ReadyToTest action (#404)
  • Contributors: Peter Baughman

0.8.0 (2019-09-26)

  • Add an demo component not inherited from rclcpp::Node (#393)
  • Contributors: Michael Carroll

0.7.6 (2019-05-30)

0.7.5 (2019-05-29)

0.7.4 (2019-05-20)

0.7.3 (2019-05-10)

0.7.2 (2019-05-08)

  • changes to avoid deprecated API's (#332)
  • Corrected publish calls with shared_ptr signature (#327)
  • Migrate launch tests to new launch_testing features & API (#318)
  • Contributors: Michel Hidalgo, William Woodall, ivanpauno

0.7.1 (2019-04-26)

  • Renamed launch file, updated to avoid redundant default actions, and set output to screen. (#326)
  • Updated constructor to const ref to NodeOptions. (#323)
  • Added basic composition launch demo. (#324)
  • Contributors: Michael Carroll, William Woodall

0.7.0 (2019-04-14)

  • Updated for new rclcpp_components package. (#319)
  • Added launch along with launch_testing as test dependencies. (#313)
  • Dropped legacy launch API usage. (#311)
  • Contributors: Michael Carroll, Michel Hidalgo

0.6.2 (2019-01-15)

0.6.1 (2018-12-13)

0.6.0 (2018-12-07)

  • Added semicolons to all RCLCPP and RCUTILS macros. (#278)
  • Contributors: Chris Lalancette

0.5.1 (2018-06-28)

0.5.0 (2018-06-27)

  • Updated launch files to account for the "old launch" getting renamespaced as launch -> launch.legacy. (#239)
  • Updated to avoid newly deprecated class loader headers. (#229)
  • Added a periodic log message while waiting for a service response.
  • Contributors: Dirk Thomas, Michael Carroll, Mikael Arguedas, William Woodall

Wiki Tutorials

This package does not provide any links to tutorials in it's rosindex metadata. You can check on the ROS Wiki Tutorials page for the package.

Launch files

No launch files found

Messages

No message files found.

Services

No service files found

Plugins

No plugins found.

Recent questions tagged composition at Robotics Stack Exchange

composition package from demos repo

action_tutorials_cpp action_tutorials_interfaces action_tutorials_py composition demo_nodes_cpp demo_nodes_cpp_native demo_nodes_py dummy_map_server dummy_robot_bringup dummy_sensors image_tools intra_process_demo lifecycle lifecycle_py logging_demo pendulum_control pendulum_msgs quality_of_service_demo_cpp quality_of_service_demo_py topic_monitor topic_statistics_demo

API Docs
Browse Code

Package Summary

Tags No category tags.
Version 0.27.2
License Apache License 2.0
Build type AMENT_CMAKE
Use RECOMMENDED

Repository Summary

Checkout URI https://github.com/ros2/demos.git
VCS Type git
VCS Version iron
Last Updated 2024-07-11
Dev Status DEVELOPED
CI status No Continuous Integration
Released RELEASED
Tags No category tags.
Contributing Help Wanted (0)
Good First Issues (0)
Pull Requests to Review (0)

Package Description

Examples for composing multiple nodes in a single process.

Additional Links

No additional links.

Maintainers

  • Aditya Pande
  • Audrow Nash
  • Michael Jeronimo

Authors

  • Dirk Thomas
  • Mabel Zhang
composition/README.md

What Is This?

This demo provides examples of three different ways to use the rclcpp_components API to compose multiple nodes in a single process.

This ROS 2 package consists of the following demo applications:

  1. dlopen_composition
  2. linktime_composition
  3. manual_composition

Build

Run the commands below to build the ROS 2 package:

colcon build --packages-up-to composition

Run

Manual Composition

Running manual_composition compiles an executable that runs the following 4 components:

  • Talker: A ROS 2 component that publishes a string
  • Listener: A ROS 2 component that prints the received string from Talker
  • Server: A ROS 2 component that adds two integers and outputs its result to Client
  • Client: A ROS 2 component that sends two integers to Server and prints the received result from Server 
ros2 run composition manual_composition

DlOpen Composition

This runs dlopen_composition which is an alternative to run-time composition by creating a generic container process and explicitly passing the libraries to load without using ROS interfaces.

The process will open each library and create one instance of each “rclcpp::Node” class in the library.

ros2 run composition dlopen_composition `ros2 pkg prefix composition`/lib/libtalker_component.so `ros2 pkg prefix composition`/lib/liblistener_component.so

Linktime Composition

Similar to previous, this runs linktime_composition which links all classes from libraries that are registered under the library_path with the linker.

ros2 run composition linktime_composition

Composition Using Launch Actions

Rather than using the command line tool to run each composition, we can automate this action with ros2 launch functionality:

ros2 launch composition composition_demo_launch.py

Verify

Manual Composition

When executed correctly, strings should be printed to terminal similar to what is shown below:

[INFO] [1674528188.026468320] [talker]: Publishing: 'Hello World: 1'
[INFO] [1674528188.027043857] [listener]: I heard: [Hello World: 1]
[INFO] [1674528189.026414368] [talker]: Publishing: 'Hello World: 2'
[INFO] [1674528189.026742015] [listener]: I heard: [Hello World: 2]
[INFO] [1674528189.032512995] [Server]: Incoming request: [a: 2, b: 3]
[INFO] [1674528189.032815843] [Client]: Got result: [5]
[INFO] [1674528190.026455807] [talker]: Publishing: 'Hello World: 3'
[INFO] [1674528190.026795770] [listener]: I heard: [Hello World: 3]
[INFO] [1674528191.026457639] [talker]: Publishing: 'Hello World: 4'
[INFO] [1674528191.026801926] [listener]: I heard: [Hello World: 4]
[INFO] [1674528191.032377264] [Server]: Incoming request: [a: 2, b: 3]
[INFO] [1674528191.032604427] [Client]: Got result: [5]
[INFO] [1674528192.026428269] [talker]: Publishing: 'Hello World: 5'
[INFO] [1674528192.026537974] [listener]: I heard: [Hello World: 5]
[INFO] [1674528193.026437034] [talker]: Publishing: 'Hello World: 6'
[INFO] [1674528193.026767708] [listener]: I heard: [Hello World: 6]
[INFO] [1674528193.032377748] [Server]: Incoming request: [a: 2, b: 3]
[INFO] [1674528193.032603036] [Client]: Got result: [5]
#...

:warning:

Note that manually-composed components will not be reflected in the ros2 component list command line tool output.

DlOpen Composition

When executed correctly, strings should be printed to terminal similar to what is shown below:

INFO] [1674529118.496557668] [dlopen_composition]: Load library /opt/ros/rolling/lib/libtalker_component.so
[INFO] [1674529118.496774575] [dlopen_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Talker>
[INFO] [1674529118.503388909] [dlopen_composition]: Load library /opt/ros/rolling/lib/liblistener_component.so
[INFO] [1674529118.503739855] [dlopen_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Listener>
[INFO] [1674529119.503505873] [talker]: Publishing: 'Hello World: 1'
[INFO] [1674529119.503770137] [listener]: I heard: [Hello World: 1]
[INFO] [1674529120.503572362] [talker]: Publishing: 'Hello World: 2'
[INFO] [1674529120.503888374] [listener]: I heard: [Hello World: 2]
[INFO] [1674529121.503503459] [talker]: Publishing: 'Hello World: 3'
[INFO] [1674529121.503628269] [listener]: I heard: [Hello World: 3]
[INFO] [1674529122.503557862] [talker]: Publishing: 'Hello World: 4'
[INFO] [1674529122.503894772] [listener]: I heard: [Hello World: 4]
[INFO] [1674529123.503574524] [talker]: Publishing: 'Hello World: 5'
[INFO] [1674529123.503884894] [listener]: I heard: [Hello World: 5]
#...

:warning:

Note that dlopen-composed components will not be reflected in the ros2 component list command line tool output.

Linktime Composition

When executed correctly, strings should be printed to terminal similar to what is shown below:

[INFO] [1674528568.091949637] [linktime_composition]: Load library
[INFO] [1674528568.091995119] [linktime_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Client>
[INFO] [1674528568.098833910] [linktime_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Listener>
[INFO] [1674528568.100669644] [linktime_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Server>
[INFO] [1674528568.102665704] [linktime_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Talker>
[INFO] [1674528569.104717098] [talker]: Publishing: 'Hello World: 1'
[INFO] [1674528569.105206993] [listener]: I heard: [Hello World: 1]
[INFO] [1674528570.099206827] [Server]: Incoming request: [a: 2, b: 3]
[INFO] [1674528570.099376432] [Client]: Got result: [5]
[INFO] [1674528570.104656875] [talker]: Publishing: 'Hello World: 2'
[INFO] [1674528570.105069514] [listener]: I heard: [Hello World: 2]
[INFO] [1674528571.104710545] [talker]: Publishing: 'Hello World: 3'
[INFO] [1674528571.105150094] [listener]: I heard: [Hello World: 3]
[INFO] [1674528572.099350955] [Server]: Incoming request: [a: 2, b: 3]
[INFO] [1674528572.099628903] [Client]: Got result: [5]
[INFO] [1674528572.104631322] [talker]: Publishing: 'Hello World: 4'
[INFO] [1674528572.104911174] [listener]: I heard: [Hello World: 4]
[INFO] [1674528573.104596009] [talker]: Publishing: 'Hello World: 5'
[INFO] [1674528573.104751214] [listener]: I heard: [Hello World: 5]
#...

:warning:

Note that linktime-composed components will not be reflected in the ros2 component list command line tool output.

Composition Using Launch Actions

When executed correctly, strings should be printed to terminal similar to what is shown below:

[INFO] [launch]: All log files can be found below /root/.ros/log/2024-05-04-23-37-06-363020-d8ff93e471d7-9387
[INFO] [launch]: Default logging verbosity is set to INFO
[INFO] [component_container-1]: process started with pid [9402]
[component_container-1] [INFO] [1714865826.695090046] [my_container]: Load Library: /opt/ros/iron/lib/libtalker_component.so
[component_container-1] [INFO] [1714865826.696388047] [my_container]: Found class: rclcpp_components::NodeFactoryTemplate<composition::Talker>
[component_container-1] [INFO] [1714865826.696435882] [my_container]: Instantiate class: rclcpp_components::NodeFactoryTemplate<composition::Talker>
[INFO] [launch_ros.actions.load_composable_nodes]: Loaded node '/talker' in container '/my_container'
[component_container-1] [INFO] [1714865826.702958710] [my_container]: Load Library: /opt/ros/iron/lib/liblistener_component.so
[component_container-1] [INFO] [1714865826.703401061] [my_container]: Found class: rclcpp_components::NodeFactoryTemplate<composition::Listener>
[component_container-1] [INFO] [1714865826.703414344] [my_container]: Instantiate class: rclcpp_components::NodeFactoryTemplate<composition::Listener>
[INFO] [launch_ros.actions.load_composable_nodes]: Loaded node '/listener' in container '/my_container'
[component_container-1] [INFO] [1714865827.701941449] [talker]: Publishing: 'Hello World: 1'
[component_container-1] [INFO] [1714865827.702047599] [listener]: I heard: [Hello World: 1]
[component_container-1] [INFO] [1714865828.701984118] [talker]: Publishing: 'Hello World: 2'
[component_container-1] [INFO] [1714865828.702154523] [listener]: I heard: [Hello World: 2]
[component_container-1] [INFO] [1714865829.702004471] [talker]: Publishing: 'Hello World: 3'
[component_container-1] [INFO] [1714865829.702176059] [listener]: I heard: [Hello World: 3]
[component_container-1] [INFO] [1714865830.701876733] [talker]: Publishing: 'Hello World: 4'
[component_container-1] [INFO] [1714865830.701965546] [listener]: I heard: [Hello World: 4]
[component_container-1] [INFO] [1714865831.701885355] [talker]: Publishing: 'Hello World: 5'
[component_container-1] [INFO] [1714865831.701984823] [listener]: I heard: [Hello World: 5]

FAQ

Q: Why use node composition?

A: Node composition avoids the overhead of marshalling and unmarshaling messages by allowing nodes to be instantiated within the same process.

References

  1. Composing multiple nodes in a single process
  2. About Composition
CHANGELOG

Changelog for package composition

0.27.2 (2024-07-10)

  • Add launch action console output in the verify section (#683)
  • Contributors: Mikael Arguedas

0.27.1 (2023-05-11)

0.27.0 (2023-04-13)

  • Change all ROS2 -> ROS 2. (#610)
  • Contributors: Chris Lalancette

0.26.0 (2023-04-11)

  • update launch file name format to match documentation (#588)
  • Contributors: Patrick Wspanialy

0.25.0 (2023-03-01)

0.24.1 (2023-02-24)

0.24.0 (2023-02-14)

  • Added README.md for composition (#598)
  • Update the demos to C++17. (#594)
  • [rolling] Update maintainers - 2022-11-07 (#589)
  • Contributors: Audrow Nash, Chris Lalancette, Gary Bey

0.23.0 (2022-11-02)

  • fix memory leak (#585)
  • Contributors: Chen Lihui

0.22.0 (2022-09-13)

0.21.0 (2022-04-29)

0.20.1 (2022-04-08)

0.20.0 (2022-03-01)

0.19.0 (2022-01-14)

0.18.0 (2021-12-17)

  • Update maintainers to Audrow Nash and Michael Jeronimo (#543)
  • Additional fixes for documentation in demos. (#538)
  • Contributors: Audrow Nash, Chris Lalancette

0.17.0 (2021-10-18)

  • Fixing deprecated subscriber callback warnings (#532)
  • Contributors: Abrar Rahman Protyasha

0.16.0 (2021-08-11)

0.15.0 (2021-05-14)

0.14.2 (2021-04-26)

0.14.1 (2021-04-19)

0.14.0 (2021-04-06)

0.13.0 (2021-03-25)

0.12.1 (2021-03-18)

0.12.0 (2021-01-25)

  • Fix leak(#480) (#481)
  • Contributors: y-okumura-isp

0.11.0 (2020-12-10)

  • Update the package.xml files with the latest Open Robotics maintainers (#466)
  • Contributors: Michael Jeronimo

0.10.1 (2020-09-21)

0.10.0 (2020-06-17)

0.9.3 (2020-06-01)

0.9.2 (2020-05-26)

0.9.1 (2020-05-12)

0.9.0 (2020-04-30)

  • Replace deprecated launch_ros usage (#437)
  • Update launch_ros action usage (#431)
  • code style only: wrap after open parenthesis if not in one line (#429)
  • Contributors: Dirk Thomas, Jacob Perron

0.8.4 (2019-11-19)

0.8.3 (2019-11-11)

0.8.2 (2019-11-08)

0.8.1 (2019-10-23)

  • Replace ready_fn with ReadyToTest action (#404)
  • Contributors: Peter Baughman

0.8.0 (2019-09-26)

  • Add an demo component not inherited from rclcpp::Node (#393)
  • Contributors: Michael Carroll

0.7.6 (2019-05-30)

0.7.5 (2019-05-29)

0.7.4 (2019-05-20)

0.7.3 (2019-05-10)

0.7.2 (2019-05-08)

  • changes to avoid deprecated API's (#332)
  • Corrected publish calls with shared_ptr signature (#327)
  • Migrate launch tests to new launch_testing features & API (#318)
  • Contributors: Michel Hidalgo, William Woodall, ivanpauno

0.7.1 (2019-04-26)

  • Renamed launch file, updated to avoid redundant default actions, and set output to screen. (#326)
  • Updated constructor to const ref to NodeOptions. (#323)
  • Added basic composition launch demo. (#324)
  • Contributors: Michael Carroll, William Woodall

0.7.0 (2019-04-14)

  • Updated for new rclcpp_components package. (#319)
  • Added launch along with launch_testing as test dependencies. (#313)
  • Dropped legacy launch API usage. (#311)
  • Contributors: Michael Carroll, Michel Hidalgo

0.6.2 (2019-01-15)

0.6.1 (2018-12-13)

0.6.0 (2018-12-07)

  • Added semicolons to all RCLCPP and RCUTILS macros. (#278)
  • Contributors: Chris Lalancette

0.5.1 (2018-06-28)

0.5.0 (2018-06-27)

  • Updated launch files to account for the "old launch" getting renamespaced as launch -> launch.legacy. (#239)
  • Updated to avoid newly deprecated class loader headers. (#229)
  • Added a periodic log message while waiting for a service response.
  • Contributors: Dirk Thomas, Michael Carroll, Mikael Arguedas, William Woodall

Wiki Tutorials

This package does not provide any links to tutorials in it's rosindex metadata. You can check on the ROS Wiki Tutorials page for the package.

Launch files

No launch files found

Messages

No message files found.

Services

No service files found

Plugins

No plugins found.

Recent questions tagged composition at Robotics Stack Exchange

composition package from demos repo

action_tutorials_cpp action_tutorials_interfaces action_tutorials_py composition demo_nodes_cpp demo_nodes_cpp_native demo_nodes_py dummy_map_server dummy_robot_bringup dummy_sensors image_tools intra_process_demo lifecycle lifecycle_py logging_demo pendulum_control pendulum_msgs quality_of_service_demo_cpp quality_of_service_demo_py topic_monitor topic_statistics_demo

API Docs
Browse Code

Package Summary

Tags No category tags.
Version 0.33.5
License Apache License 2.0
Build type AMENT_CMAKE
Use RECOMMENDED

Repository Summary

Checkout URI https://github.com/ros2/demos.git
VCS Type git
VCS Version jazzy
Last Updated 2024-09-06
Dev Status DEVELOPED
CI status No Continuous Integration
Released RELEASED
Tags No category tags.
Contributing Help Wanted (0)
Good First Issues (0)
Pull Requests to Review (0)

Package Description

Examples for composing multiple nodes in a single process.

Additional Links

No additional links.

Maintainers

  • Aditya Pande
  • Audrow Nash

Authors

  • Dirk Thomas
  • Mabel Zhang
composition/README.md

What Is This?

This demo provides examples of three different ways to use the rclcpp_components API to compose multiple nodes in a single process.

This ROS 2 package consists of the following demo applications:

  1. dlopen_composition
  2. linktime_composition
  3. manual_composition

Build

Run the commands below to build the ROS 2 package:

colcon build --packages-up-to composition

Run

Manual Composition

Running manual_composition compiles an executable that runs the following 4 components:

  • Talker: A ROS 2 component that publishes a string
  • Listener: A ROS 2 component that prints the received string from Talker
  • Server: A ROS 2 component that adds two integers and outputs its result to Client
  • Client: A ROS 2 component that sends two integers to Server and prints the received result from Server 
ros2 run composition manual_composition

DlOpen Composition

This runs dlopen_composition which is an alternative to run-time composition by creating a generic container process and explicitly passing the libraries to load without using ROS interfaces.

The process will open each library and create one instance of each “rclcpp::Node” class in the library.

ros2 run composition dlopen_composition `ros2 pkg prefix composition`/lib/libtalker_component.so `ros2 pkg prefix composition`/lib/liblistener_component.so

Linktime Composition

Similar to previous, this runs linktime_composition which links all classes from libraries that are registered under the library_path with the linker.

ros2 run composition linktime_composition

Composition Using Launch Actions

Rather than using the command line tool to run each composition, we can automate this action with ros2 launch functionality:

ros2 launch composition composition_demo_launch.py

Verify

Manual Composition

When executed correctly, strings should be printed to terminal similar to what is shown below:

[INFO] [1674528188.026468320] [talker]: Publishing: 'Hello World: 1'
[INFO] [1674528188.027043857] [listener]: I heard: [Hello World: 1]
[INFO] [1674528189.026414368] [talker]: Publishing: 'Hello World: 2'
[INFO] [1674528189.026742015] [listener]: I heard: [Hello World: 2]
[INFO] [1674528189.032512995] [Server]: Incoming request: [a: 2, b: 3]
[INFO] [1674528189.032815843] [Client]: Got result: [5]
[INFO] [1674528190.026455807] [talker]: Publishing: 'Hello World: 3'
[INFO] [1674528190.026795770] [listener]: I heard: [Hello World: 3]
[INFO] [1674528191.026457639] [talker]: Publishing: 'Hello World: 4'
[INFO] [1674528191.026801926] [listener]: I heard: [Hello World: 4]
[INFO] [1674528191.032377264] [Server]: Incoming request: [a: 2, b: 3]
[INFO] [1674528191.032604427] [Client]: Got result: [5]
[INFO] [1674528192.026428269] [talker]: Publishing: 'Hello World: 5'
[INFO] [1674528192.026537974] [listener]: I heard: [Hello World: 5]
[INFO] [1674528193.026437034] [talker]: Publishing: 'Hello World: 6'
[INFO] [1674528193.026767708] [listener]: I heard: [Hello World: 6]
[INFO] [1674528193.032377748] [Server]: Incoming request: [a: 2, b: 3]
[INFO] [1674528193.032603036] [Client]: Got result: [5]
#...

:warning:

Note that manually-composed components will not be reflected in the ros2 component list command line tool output.

DlOpen Composition

When executed correctly, strings should be printed to terminal similar to what is shown below:

INFO] [1674529118.496557668] [dlopen_composition]: Load library /opt/ros/rolling/lib/libtalker_component.so
[INFO] [1674529118.496774575] [dlopen_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Talker>
[INFO] [1674529118.503388909] [dlopen_composition]: Load library /opt/ros/rolling/lib/liblistener_component.so
[INFO] [1674529118.503739855] [dlopen_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Listener>
[INFO] [1674529119.503505873] [talker]: Publishing: 'Hello World: 1'
[INFO] [1674529119.503770137] [listener]: I heard: [Hello World: 1]
[INFO] [1674529120.503572362] [talker]: Publishing: 'Hello World: 2'
[INFO] [1674529120.503888374] [listener]: I heard: [Hello World: 2]
[INFO] [1674529121.503503459] [talker]: Publishing: 'Hello World: 3'
[INFO] [1674529121.503628269] [listener]: I heard: [Hello World: 3]
[INFO] [1674529122.503557862] [talker]: Publishing: 'Hello World: 4'
[INFO] [1674529122.503894772] [listener]: I heard: [Hello World: 4]
[INFO] [1674529123.503574524] [talker]: Publishing: 'Hello World: 5'
[INFO] [1674529123.503884894] [listener]: I heard: [Hello World: 5]
#...

:warning:

Note that dlopen-composed components will not be reflected in the ros2 component list command line tool output.

Linktime Composition

When executed correctly, strings should be printed to terminal similar to what is shown below:

[INFO] [1674528568.091949637] [linktime_composition]: Load library
[INFO] [1674528568.091995119] [linktime_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Client>
[INFO] [1674528568.098833910] [linktime_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Listener>
[INFO] [1674528568.100669644] [linktime_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Server>
[INFO] [1674528568.102665704] [linktime_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Talker>
[INFO] [1674528569.104717098] [talker]: Publishing: 'Hello World: 1'
[INFO] [1674528569.105206993] [listener]: I heard: [Hello World: 1]
[INFO] [1674528570.099206827] [Server]: Incoming request: [a: 2, b: 3]
[INFO] [1674528570.099376432] [Client]: Got result: [5]
[INFO] [1674528570.104656875] [talker]: Publishing: 'Hello World: 2'
[INFO] [1674528570.105069514] [listener]: I heard: [Hello World: 2]
[INFO] [1674528571.104710545] [talker]: Publishing: 'Hello World: 3'
[INFO] [1674528571.105150094] [listener]: I heard: [Hello World: 3]
[INFO] [1674528572.099350955] [Server]: Incoming request: [a: 2, b: 3]
[INFO] [1674528572.099628903] [Client]: Got result: [5]
[INFO] [1674528572.104631322] [talker]: Publishing: 'Hello World: 4'
[INFO] [1674528572.104911174] [listener]: I heard: [Hello World: 4]
[INFO] [1674528573.104596009] [talker]: Publishing: 'Hello World: 5'
[INFO] [1674528573.104751214] [listener]: I heard: [Hello World: 5]
#...

:warning:

Note that linktime-composed components will not be reflected in the ros2 component list command line tool output.

Composition Using Launch Actions

When executed correctly, strings should be printed to terminal similar to what is shown below:

[INFO] [launch]: All log files can be found below /root/.ros/log/2024-05-04-23-37-06-363020-d8ff93e471d7-9387
[INFO] [launch]: Default logging verbosity is set to INFO
[INFO] [component_container-1]: process started with pid [9402]
[component_container-1] [INFO] [1714865826.695090046] [my_container]: Load Library: /opt/ros/jazzy/lib/libtalker_component.so
[component_container-1] [INFO] [1714865826.696388047] [my_container]: Found class: rclcpp_components::NodeFactoryTemplate<composition::Talker>
[component_container-1] [INFO] [1714865826.696435882] [my_container]: Instantiate class: rclcpp_components::NodeFactoryTemplate<composition::Talker>
[INFO] [launch_ros.actions.load_composable_nodes]: Loaded node '/talker' in container '/my_container'
[component_container-1] [INFO] [1714865826.702958710] [my_container]: Load Library: /opt/ros/jazzy/lib/liblistener_component.so
[component_container-1] [INFO] [1714865826.703401061] [my_container]: Found class: rclcpp_components::NodeFactoryTemplate<composition::Listener>
[component_container-1] [INFO] [1714865826.703414344] [my_container]: Instantiate class: rclcpp_components::NodeFactoryTemplate<composition::Listener>
[INFO] [launch_ros.actions.load_composable_nodes]: Loaded node '/listener' in container '/my_container'
[component_container-1] [INFO] [1714865827.701941449] [talker]: Publishing: 'Hello World: 1'
[component_container-1] [INFO] [1714865827.702047599] [listener]: I heard: [Hello World: 1]
[component_container-1] [INFO] [1714865828.701984118] [talker]: Publishing: 'Hello World: 2'
[component_container-1] [INFO] [1714865828.702154523] [listener]: I heard: [Hello World: 2]
[component_container-1] [INFO] [1714865829.702004471] [talker]: Publishing: 'Hello World: 3'
[component_container-1] [INFO] [1714865829.702176059] [listener]: I heard: [Hello World: 3]
[component_container-1] [INFO] [1714865830.701876733] [talker]: Publishing: 'Hello World: 4'
[component_container-1] [INFO] [1714865830.701965546] [listener]: I heard: [Hello World: 4]
[component_container-1] [INFO] [1714865831.701885355] [talker]: Publishing: 'Hello World: 5'
[component_container-1] [INFO] [1714865831.701984823] [listener]: I heard: [Hello World: 5]

FAQ

Q: Why use node composition?

A: Node composition avoids the overhead of marshalling and unmarshaling messages by allowing nodes to be instantiated within the same process.

References

  1. Composing multiple nodes in a single process
  2. About Composition
CHANGELOG

Changelog for package composition

0.33.5 (2024-09-06)

0.33.4 (2024-06-27)

0.33.3 (2024-05-13)

  • [composition] add launch action console output in the verify section (#677) (#681) (cherry picked from commit 34d29db73e78a84a174ad8699a2d646b0eeb1cdf) Co-authored-by: Mikael Arguedas <<mikael.arguedas@gmail.com>>
  • Contributors: mergify[bot]

0.33.2 (2024-03-28)

  • Update maintainer list in package.xml files (#665)
  • Contributors: Michael Jeronimo

0.33.1 (2024-02-07)

0.33.0 (2024-01-24)

  • Migrate std::bind calls to lambda expressions (#659)
  • Contributors: Felipe Gomes de Melo

0.32.1 (2023-12-26)

0.32.0 (2023-11-06)

0.31.1 (2023-09-07)

0.31.0 (2023-08-21)

0.30.1 (2023-07-11)

0.30.0 (2023-06-12)

0.29.0 (2023-06-07)

0.28.1 (2023-05-11)

0.28.0 (2023-04-27)

0.27.0 (2023-04-13)

  • Change all ROS2 -> ROS 2. (#610)
  • Contributors: Chris Lalancette

0.26.0 (2023-04-11)

  • update launch file name format to match documentation (#588)
  • Contributors: Patrick Wspanialy

0.25.0 (2023-03-01)

0.24.1 (2023-02-24)

0.24.0 (2023-02-14)

  • Added README.md for composition (#598)
  • Update the demos to C++17. (#594)
  • [rolling] Update maintainers - 2022-11-07 (#589)
  • Contributors: Audrow Nash, Chris Lalancette, Gary Bey

0.23.0 (2022-11-02)

  • fix memory leak (#585)
  • Contributors: Chen Lihui

0.22.0 (2022-09-13)

0.21.0 (2022-04-29)

0.20.1 (2022-04-08)

0.20.0 (2022-03-01)

0.19.0 (2022-01-14)

0.18.0 (2021-12-17)

  • Update maintainers to Audrow Nash and Michael Jeronimo (#543)
  • Additional fixes for documentation in demos. (#538)
  • Contributors: Audrow Nash, Chris Lalancette

0.17.0 (2021-10-18)

  • Fixing deprecated subscriber callback warnings (#532)
  • Contributors: Abrar Rahman Protyasha

0.16.0 (2021-08-11)

0.15.0 (2021-05-14)

0.14.2 (2021-04-26)

0.14.1 (2021-04-19)

0.14.0 (2021-04-06)

0.13.0 (2021-03-25)

0.12.1 (2021-03-18)

0.12.0 (2021-01-25)

  • Fix leak(#480) (#481)
  • Contributors: y-okumura-isp

0.11.0 (2020-12-10)

  • Update the package.xml files with the latest Open Robotics maintainers (#466)
  • Contributors: Michael Jeronimo

0.10.1 (2020-09-21)

0.10.0 (2020-06-17)

0.9.3 (2020-06-01)

0.9.2 (2020-05-26)

0.9.1 (2020-05-12)

0.9.0 (2020-04-30)

  • Replace deprecated launch_ros usage (#437)
  • Update launch_ros action usage (#431)
  • code style only: wrap after open parenthesis if not in one line (#429)
  • Contributors: Dirk Thomas, Jacob Perron

0.8.4 (2019-11-19)

0.8.3 (2019-11-11)

0.8.2 (2019-11-08)

0.8.1 (2019-10-23)

  • Replace ready_fn with ReadyToTest action (#404)
  • Contributors: Peter Baughman

0.8.0 (2019-09-26)

  • Add an demo component not inherited from rclcpp::Node (#393)
  • Contributors: Michael Carroll

0.7.6 (2019-05-30)

0.7.5 (2019-05-29)

0.7.4 (2019-05-20)

0.7.3 (2019-05-10)

0.7.2 (2019-05-08)

  • changes to avoid deprecated API's (#332)
  • Corrected publish calls with shared_ptr signature (#327)
  • Migrate launch tests to new launch_testing features & API (#318)
  • Contributors: Michel Hidalgo, William Woodall, ivanpauno

0.7.1 (2019-04-26)

  • Renamed launch file, updated to avoid redundant default actions, and set output to screen. (#326)
  • Updated constructor to const ref to NodeOptions. (#323)
  • Added basic composition launch demo. (#324)
  • Contributors: Michael Carroll, William Woodall

0.7.0 (2019-04-14)

  • Updated for new rclcpp_components package. (#319)
  • Added launch along with launch_testing as test dependencies. (#313)
  • Dropped legacy launch API usage. (#311)
  • Contributors: Michael Carroll, Michel Hidalgo

0.6.2 (2019-01-15)

0.6.1 (2018-12-13)

0.6.0 (2018-12-07)

  • Added semicolons to all RCLCPP and RCUTILS macros. (#278)
  • Contributors: Chris Lalancette

0.5.1 (2018-06-28)

0.5.0 (2018-06-27)

  • Updated launch files to account for the "old launch" getting renamespaced as launch -> launch.legacy. (#239)
  • Updated to avoid newly deprecated class loader headers. (#229)
  • Added a periodic log message while waiting for a service response.
  • Contributors: Dirk Thomas, Michael Carroll, Mikael Arguedas, William Woodall

Wiki Tutorials

This package does not provide any links to tutorials in it's rosindex metadata. You can check on the ROS Wiki Tutorials page for the package.

Launch files

No launch files found

Messages

No message files found.

Services

No service files found

Plugins

No plugins found.

Recent questions tagged composition at Robotics Stack Exchange

composition package from demos repo

action_tutorials_cpp action_tutorials_py composition demo_nodes_cpp demo_nodes_cpp_native demo_nodes_py dummy_map_server dummy_robot_bringup dummy_sensors image_tools intra_process_demo lifecycle lifecycle_py logging_demo pendulum_control pendulum_msgs quality_of_service_demo_cpp quality_of_service_demo_py topic_monitor topic_statistics_demo

API Docs
Browse Code

Package Summary

Tags No category tags.
Version 0.35.1
License Apache License 2.0
Build type AMENT_CMAKE
Use RECOMMENDED

Repository Summary

Checkout URI https://github.com/ros2/demos.git
VCS Type git
VCS Version rolling
Last Updated 2024-11-20
Dev Status DEVELOPED
CI status No Continuous Integration
Released RELEASED
Tags No category tags.
Contributing Help Wanted (0)
Good First Issues (0)
Pull Requests to Review (0)

Package Description

Examples for composing multiple nodes in a single process.

Additional Links

No additional links.

Maintainers

  • Aditya Pande
  • Audrow Nash

Authors

  • Dirk Thomas
  • Mabel Zhang
composition/README.md

What Is This?

This demo provides examples of three different ways to use the rclcpp_components API to compose multiple nodes in a single process.

This ROS 2 package consists of the following demo applications:

  1. dlopen_composition
  2. linktime_composition
  3. manual_composition

Build

Run the commands below to build the ROS 2 package:

colcon build --packages-up-to composition

Run

Manual Composition

Running manual_composition compiles an executable that runs the following 4 components:

  • Talker: A ROS 2 component that publishes a string
  • Listener: A ROS 2 component that prints the received string from Talker
  • Server: A ROS 2 component that adds two integers and outputs its result to Client
  • Client: A ROS 2 component that sends two integers to Server and prints the received result from Server 
ros2 run composition manual_composition

DlOpen Composition

This runs dlopen_composition which is an alternative to run-time composition by creating a generic container process and explicitly passing the libraries to load without using ROS interfaces.

The process will open each library and create one instance of each “rclcpp::Node” class in the library.

ros2 run composition dlopen_composition `ros2 pkg prefix composition`/lib/libtalker_component.so `ros2 pkg prefix composition`/lib/liblistener_component.so

Linktime Composition

Similar to previous, this runs linktime_composition which links all classes from libraries that are registered under the library_path with the linker.

ros2 run composition linktime_composition

Composition Using Launch Actions

Rather than using the command line tool to run each composition, we can automate this action with ros2 launch functionality:

ros2 launch composition composition_demo_launch.py

Verify

Manual Composition

When executed correctly, strings should be printed to terminal similar to what is shown below:

[INFO] [1674528188.026468320] [talker]: Publishing: 'Hello World: 1'
[INFO] [1674528188.027043857] [listener]: I heard: [Hello World: 1]
[INFO] [1674528189.026414368] [talker]: Publishing: 'Hello World: 2'
[INFO] [1674528189.026742015] [listener]: I heard: [Hello World: 2]
[INFO] [1674528189.032512995] [Server]: Incoming request: [a: 2, b: 3]
[INFO] [1674528189.032815843] [Client]: Got result: [5]
[INFO] [1674528190.026455807] [talker]: Publishing: 'Hello World: 3'
[INFO] [1674528190.026795770] [listener]: I heard: [Hello World: 3]
[INFO] [1674528191.026457639] [talker]: Publishing: 'Hello World: 4'
[INFO] [1674528191.026801926] [listener]: I heard: [Hello World: 4]
[INFO] [1674528191.032377264] [Server]: Incoming request: [a: 2, b: 3]
[INFO] [1674528191.032604427] [Client]: Got result: [5]
[INFO] [1674528192.026428269] [talker]: Publishing: 'Hello World: 5'
[INFO] [1674528192.026537974] [listener]: I heard: [Hello World: 5]
[INFO] [1674528193.026437034] [talker]: Publishing: 'Hello World: 6'
[INFO] [1674528193.026767708] [listener]: I heard: [Hello World: 6]
[INFO] [1674528193.032377748] [Server]: Incoming request: [a: 2, b: 3]
[INFO] [1674528193.032603036] [Client]: Got result: [5]
#...

:warning:

Note that manually-composed components will not be reflected in the ros2 component list command line tool output.

DlOpen Composition

When executed correctly, strings should be printed to terminal similar to what is shown below:

INFO] [1674529118.496557668] [dlopen_composition]: Load library /opt/ros/rolling/lib/libtalker_component.so
[INFO] [1674529118.496774575] [dlopen_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Talker>
[INFO] [1674529118.503388909] [dlopen_composition]: Load library /opt/ros/rolling/lib/liblistener_component.so
[INFO] [1674529118.503739855] [dlopen_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Listener>
[INFO] [1674529119.503505873] [talker]: Publishing: 'Hello World: 1'
[INFO] [1674529119.503770137] [listener]: I heard: [Hello World: 1]
[INFO] [1674529120.503572362] [talker]: Publishing: 'Hello World: 2'
[INFO] [1674529120.503888374] [listener]: I heard: [Hello World: 2]
[INFO] [1674529121.503503459] [talker]: Publishing: 'Hello World: 3'
[INFO] [1674529121.503628269] [listener]: I heard: [Hello World: 3]
[INFO] [1674529122.503557862] [talker]: Publishing: 'Hello World: 4'
[INFO] [1674529122.503894772] [listener]: I heard: [Hello World: 4]
[INFO] [1674529123.503574524] [talker]: Publishing: 'Hello World: 5'
[INFO] [1674529123.503884894] [listener]: I heard: [Hello World: 5]
#...

:warning:

Note that dlopen-composed components will not be reflected in the ros2 component list command line tool output.

Linktime Composition

When executed correctly, strings should be printed to terminal similar to what is shown below:

[INFO] [1674528568.091949637] [linktime_composition]: Load library
[INFO] [1674528568.091995119] [linktime_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Client>
[INFO] [1674528568.098833910] [linktime_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Listener>
[INFO] [1674528568.100669644] [linktime_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Server>
[INFO] [1674528568.102665704] [linktime_composition]: Instantiate class rclcpp_components::NodeFactoryTemplate<composition::Talker>
[INFO] [1674528569.104717098] [talker]: Publishing: 'Hello World: 1'
[INFO] [1674528569.105206993] [listener]: I heard: [Hello World: 1]
[INFO] [1674528570.099206827] [Server]: Incoming request: [a: 2, b: 3]
[INFO] [1674528570.099376432] [Client]: Got result: [5]
[INFO] [1674528570.104656875] [talker]: Publishing: 'Hello World: 2'
[INFO] [1674528570.105069514] [listener]: I heard: [Hello World: 2]
[INFO] [1674528571.104710545] [talker]: Publishing: 'Hello World: 3'
[INFO] [1674528571.105150094] [listener]: I heard: [Hello World: 3]
[INFO] [1674528572.099350955] [Server]: Incoming request: [a: 2, b: 3]
[INFO] [1674528572.099628903] [Client]: Got result: [5]
[INFO] [1674528572.104631322] [talker]: Publishing: 'Hello World: 4'
[INFO] [1674528572.104911174] [listener]: I heard: [Hello World: 4]
[INFO] [1674528573.104596009] [talker]: Publishing: 'Hello World: 5'
[INFO] [1674528573.104751214] [listener]: I heard: [Hello World: 5]
#...

:warning:

Note that linktime-composed components will not be reflected in the ros2 component list command line tool output.

Composition Using Launch Actions

When executed correctly, strings should be printed to terminal similar to what is shown below:

[INFO] [launch]: All log files can be found below /root/.ros/log/2024-05-04-23-37-06-363020-d8ff93e471d7-9387
[INFO] [launch]: Default logging verbosity is set to INFO
[INFO] [component_container-1]: process started with pid [9402]
[component_container-1] [INFO] [1714865826.695090046] [my_container]: Load Library: /opt/ros/rolling/lib/libtalker_component.so
[component_container-1] [INFO] [1714865826.696388047] [my_container]: Found class: rclcpp_components::NodeFactoryTemplate<composition::Talker>
[component_container-1] [INFO] [1714865826.696435882] [my_container]: Instantiate class: rclcpp_components::NodeFactoryTemplate<composition::Talker>
[INFO] [launch_ros.actions.load_composable_nodes]: Loaded node '/talker' in container '/my_container'
[component_container-1] [INFO] [1714865826.702958710] [my_container]: Load Library: /opt/ros/rolling/lib/liblistener_component.so
[component_container-1] [INFO] [1714865826.703401061] [my_container]: Found class: rclcpp_components::NodeFactoryTemplate<composition::Listener>
[component_container-1] [INFO] [1714865826.703414344] [my_container]: Instantiate class: rclcpp_components::NodeFactoryTemplate<composition::Listener>
[INFO] [launch_ros.actions.load_composable_nodes]: Loaded node '/listener' in container '/my_container'
[component_container-1] [INFO] [1714865827.701941449] [talker]: Publishing: 'Hello World: 1'
[component_container-1] [INFO] [1714865827.702047599] [listener]: I heard: [Hello World: 1]
[component_container-1] [INFO] [1714865828.701984118] [talker]: Publishing: 'Hello World: 2'
[component_container-1] [INFO] [1714865828.702154523] [listener]: I heard: [Hello World: 2]
[component_container-1] [INFO] [1714865829.702004471] [talker]: Publishing: 'Hello World: 3'
[component_container-1] [INFO] [1714865829.702176059] [listener]: I heard: [Hello World: 3]
[component_container-1] [INFO] [1714865830.701876733] [talker]: Publishing: 'Hello World: 4'
[component_container-1] [INFO] [1714865830.701965546] [listener]: I heard: [Hello World: 4]
[component_container-1] [INFO] [1714865831.701885355] [talker]: Publishing: 'Hello World: 5'
[component_container-1] [INFO] [1714865831.701984823] [listener]: I heard: [Hello World: 5]

FAQ

Q: Why use node composition?

A: Node composition avoids the overhead of marshalling and unmarshaling messages by allowing nodes to be instantiated within the same process.

References

  1. Composing multiple nodes in a single process
  2. About Composition
CHANGELOG

Changelog for package composition

0.35.1 (2024-11-20)

0.35.0 (2024-10-03)

  • Fix typo in composition comment (#703)
  • Contributors: Christophe Bedard

0.34.2 (2024-07-29)

0.34.1 (2024-06-17)

  • Change references from "jazzy" to "rolling" on the rolling branch. (#687)
  • [composition] add launch action console output in the verify section (#677)
  • Contributors: Chris Lalancette, Mikael Arguedas

0.34.0 (2024-04-26)

0.33.2 (2024-03-28)

  • Update maintainer list in package.xml files (#665)
  • Contributors: Michael Jeronimo

0.33.1 (2024-02-07)

0.33.0 (2024-01-24)

  • Migrate std::bind calls to lambda expressions (#659)
  • Contributors: Felipe Gomes de Melo

0.32.1 (2023-12-26)

0.32.0 (2023-11-06)

0.31.1 (2023-09-07)

0.31.0 (2023-08-21)

0.30.1 (2023-07-11)

0.30.0 (2023-06-12)

0.29.0 (2023-06-07)

0.28.1 (2023-05-11)

0.28.0 (2023-04-27)

0.27.0 (2023-04-13)

  • Change all ROS2 -> ROS 2. (#610)
  • Contributors: Chris Lalancette

0.26.0 (2023-04-11)

  • update launch file name format to match documentation (#588)
  • Contributors: Patrick Wspanialy

0.25.0 (2023-03-01)

0.24.1 (2023-02-24)

0.24.0 (2023-02-14)

  • Added README.md for composition (#598)
  • Update the demos to C++17. (#594)
  • [rolling] Update maintainers - 2022-11-07 (#589)
  • Contributors: Audrow Nash, Chris Lalancette, Gary Bey

0.23.0 (2022-11-02)

  • fix memory leak (#585)
  • Contributors: Chen Lihui

0.22.0 (2022-09-13)

0.21.0 (2022-04-29)

0.20.1 (2022-04-08)

0.20.0 (2022-03-01)

0.19.0 (2022-01-14)

0.18.0 (2021-12-17)

  • Update maintainers to Audrow Nash and Michael Jeronimo (#543)
  • Additional fixes for documentation in demos. (#538)
  • Contributors: Audrow Nash, Chris Lalancette

0.17.0 (2021-10-18)

  • Fixing deprecated subscriber callback warnings (#532)
  • Contributors: Abrar Rahman Protyasha

0.16.0 (2021-08-11)

0.15.0 (2021-05-14)

0.14.2 (2021-04-26)

0.14.1 (2021-04-19)

0.14.0 (2021-04-06)

0.13.0 (2021-03-25)

0.12.1 (2021-03-18)

0.12.0 (2021-01-25)

  • Fix leak(#480) (#481)
  • Contributors: y-okumura-isp

0.11.0 (2020-12-10)

  • Update the package.xml files with the latest Open Robotics maintainers (#466)
  • Contributors: Michael Jeronimo

0.10.1 (2020-09-21)

0.10.0 (2020-06-17)

0.9.3 (2020-06-01)

0.9.2 (2020-05-26)

0.9.1 (2020-05-12)

0.9.0 (2020-04-30)

  • Replace deprecated launch_ros usage (#437)
  • Update launch_ros action usage (#431)
  • code style only: wrap after open parenthesis if not in one line (#429)
  • Contributors: Dirk Thomas, Jacob Perron

0.8.4 (2019-11-19)

0.8.3 (2019-11-11)

0.8.2 (2019-11-08)

0.8.1 (2019-10-23)

  • Replace ready_fn with ReadyToTest action (#404)
  • Contributors: Peter Baughman

0.8.0 (2019-09-26)

  • Add an demo component not inherited from rclcpp::Node (#393)
  • Contributors: Michael Carroll

0.7.6 (2019-05-30)

0.7.5 (2019-05-29)

0.7.4 (2019-05-20)

0.7.3 (2019-05-10)

0.7.2 (2019-05-08)

  • changes to avoid deprecated API's (#332)
  • Corrected publish calls with shared_ptr signature (#327)
  • Migrate launch tests to new launch_testing features & API (#318)
  • Contributors: Michel Hidalgo, William Woodall, ivanpauno

0.7.1 (2019-04-26)

  • Renamed launch file, updated to avoid redundant default actions, and set output to screen. (#326)
  • Updated constructor to const ref to NodeOptions. (#323)
  • Added basic composition launch demo. (#324)
  • Contributors: Michael Carroll, William Woodall

0.7.0 (2019-04-14)

  • Updated for new rclcpp_components package. (#319)
  • Added launch along with launch_testing as test dependencies. (#313)
  • Dropped legacy launch API usage. (#311)
  • Contributors: Michael Carroll, Michel Hidalgo

0.6.2 (2019-01-15)

0.6.1 (2018-12-13)

0.6.0 (2018-12-07)

  • Added semicolons to all RCLCPP and RCUTILS macros. (#278)
  • Contributors: Chris Lalancette

0.5.1 (2018-06-28)

0.5.0 (2018-06-27)

  • Updated launch files to account for the "old launch" getting renamespaced as launch -> launch.legacy. (#239)
  • Updated to avoid newly deprecated class loader headers. (#229)
  • Added a periodic log message while waiting for a service response.
  • Contributors: Dirk Thomas, Michael Carroll, Mikael Arguedas, William Woodall

Wiki Tutorials

This package does not provide any links to tutorials in it's rosindex metadata. You can check on the ROS Wiki Tutorials page for the package.

Launch files

No launch files found

Messages

No message files found.

Services

No service files found

Plugins

No plugins found.

Recent questions tagged composition at Robotics Stack Exchange

composition package from demos repo

action_tutorials_cpp action_tutorials_interfaces action_tutorials_py composition demo_nodes_cpp demo_nodes_cpp_native demo_nodes_py dummy_map_server dummy_robot_bringup dummy_sensors image_tools intra_process_demo lifecycle logging_demo pendulum_control pendulum_msgs quality_of_service_demo_cpp quality_of_service_demo_py topic_monitor topic_statistics_demo

API Docs
Browse Code

Package Summary

Tags No category tags.
Version 0.14.4
License Apache License 2.0
Build type AMENT_CMAKE
Use RECOMMENDED

Repository Summary

Checkout URI https://github.com/ros2/demos.git
VCS Type git
VCS Version galactic
Last Updated 2022-12-07
Dev Status DEVELOPED
CI status No Continuous Integration
Released RELEASED
Tags No category tags.
Contributing Help Wanted (0)
Good First Issues (0)
Pull Requests to Review (0)

Package Description

Examples for composing multiple nodes in a single process.

Additional Links

No additional links.

Maintainers

  • Mabel Zhang
  • Michael Jeronimo

Authors

  • Dirk Thomas
README
No README found. No README in repository either.
CHANGELOG

Changelog for package composition

0.14.4 (2022-12-06)

0.14.3 (2021-05-10)

0.14.2 (2021-04-26)

0.14.1 (2021-04-19)

0.14.0 (2021-04-06)

0.13.0 (2021-03-25)

0.12.1 (2021-03-18)

0.12.0 (2021-01-25)

  • Fix leak(#480) (#481)
  • Contributors: y-okumura-isp

0.11.0 (2020-12-10)

  • Update the package.xml files with the latest Open Robotics maintainers (#466)
  • Contributors: Michael Jeronimo

0.10.1 (2020-09-21)

0.10.0 (2020-06-17)

0.9.3 (2020-06-01)

0.9.2 (2020-05-26)

0.9.1 (2020-05-12)

0.9.0 (2020-04-30)

  • Replace deprecated launch_ros usage (#437)
  • Update launch_ros action usage (#431)
  • code style only: wrap after open parenthesis if not in one line (#429)
  • Contributors: Dirk Thomas, Jacob Perron

0.8.4 (2019-11-19)

0.8.3 (2019-11-11)

0.8.2 (2019-11-08)

0.8.1 (2019-10-23)

  • Replace ready_fn with ReadyToTest action (#404)
  • Contributors: Peter Baughman

0.8.0 (2019-09-26)

  • Add an demo component not inherited from rclcpp::Node (#393)
  • Contributors: Michael Carroll

0.7.6 (2019-05-30)

0.7.5 (2019-05-29)

0.7.4 (2019-05-20)

0.7.3 (2019-05-10)

0.7.2 (2019-05-08)

  • changes to avoid deprecated API's (#332)
  • Corrected publish calls with shared_ptr signature (#327)
  • Migrate launch tests to new launch_testing features & API (#318)
  • Contributors: Michel Hidalgo, William Woodall, ivanpauno

0.7.1 (2019-04-26)

  • Renamed launch file, updated to avoid redundant default actions, and set output to screen. (#326)
  • Updated constructor to const ref to NodeOptions. (#323)
  • Added basic composition launch demo. (#324)
  • Contributors: Michael Carroll, William Woodall

0.7.0 (2019-04-14)

  • Updated for new rclcpp_components package. (#319)
  • Added launch along with launch_testing as test dependencies. (#313)
  • Dropped legacy launch API usage. (#311)
  • Contributors: Michael Carroll, Michel Hidalgo

0.6.2 (2019-01-15)

0.6.1 (2018-12-13)

0.6.0 (2018-12-07)

  • Added semicolons to all RCLCPP and RCUTILS macros. (#278)
  • Contributors: Chris Lalancette

0.5.1 (2018-06-28)

0.5.0 (2018-06-27)

  • Updated launch files to account for the "old launch" getting renamespaced as launch -> launch.legacy. (#239)
  • Updated to avoid newly deprecated class loader headers. (#229)
  • Added a periodic log message while waiting for a service response.
  • Contributors: Dirk Thomas, Michael Carroll, Mikael Arguedas, William Woodall

Wiki Tutorials

This package does not provide any links to tutorials in it's rosindex metadata. You can check on the ROS Wiki Tutorials page for the package.

Launch files

No launch files found

Messages

No message files found.

Services

No service files found

Plugins

No plugins found.

Recent questions tagged composition at Robotics Stack Exchange