domain_bridge

A ROS 2 domain bridge. Bridges ROS communication between different ROS domain IDs.

See the design document for more details about how the bridge works.

Prerequisites

• ROS 2 (Galactic or newer)

Installation

Ubuntu 20.04

Replace $ROS_DISTRO with the ROS codename (e.g. galactic):

sudo apt install ros-$ROS_DISTRO-domain-bridge

From source

Prerequisites:

• Git
• colcon (colcon_cmake)

mkdir -p domain_bridge_ws/src
cd domain_bridge_ws
git clone https://github.com/ros2/domain_bridge.git src/
colcon build

Usage

CLI

There is a standalone executable that can be configured via a YAML file.

You must provide the path to a YAML configuration file as the last argument to the executable. For example,

ros2 run domain_bridge domain_bridge examples/example_bridge_config.yaml

There are also options to override the domain IDs set for all entities in the YAML config, for example,

ros2 run domain_bridge domain_bridge --from 7 --to 8 examples/example_bridge_config.yaml

Use the --help option for more usage information:

ros2 run domain_bridge domain_bridge --help

You can also load composable nodes alongside the domain bridge to allow for intra-process communication. Use the extra argument domain_id to set the domain ID for each loaded component:

ros2 component load /ComponentManager composition composition::Talker -e domain_id:=1
ros2 component load /ComponentManager composition composition::Listener -e domain_id:=2

Launch

You can also use the example launch script, which takes a required launch argument config:

ros2 launch domain_bridge domain_bridge.launch.xml config:=examples/example_bridge_config.yaml

You can also override domain IDs with optional launch arguments from_domain and to_domain.

To reverse the from and to domain IDs for a topic, set the reversed argument to true.

To enable bidirectional bridging of a topic, set the bidirectional argument to true.

Here is an example of including the domain bridge launch script into your own:

<launch>
  <include file="$(find-pkg-share domain_bridge)/launch/domain_bridge.launch.xml">
    <arg name="config" value="$(find-pkg-share domain_bridge)/examples/example_bridge_config.yaml" />
    <!-- Optionally override domain IDs -->
    <arg name="from_domain" value="42" />
    <arg name="to_domain" value="43" />
  </include>
</launch>

C++ library

There is a C++ API that can be integrated into your own process, you can find the API docs here.