Launch file for combined gzserver + bridge

[caguero]

🎉 New feature

Part of #544

Summary

This patch lets you combine the functionality from #530 and #532 into a single launch file.

How to test it?

Use the provided ros_gz_sim.launch.py (modify config_file accordingly) to run the bridge as an executable

ros2 launch ros_gz_sim ros_gz_sim.launch.py world_sdf_file:=empty.sdf config_file:=/home/caguero/ros_gz_ws/src/ros_gz/ros_gz_bridge/test/config/full.yaml

You should see messages of gzserver loading. Additionally, verify that you see the /ros_chatter topic:

caguero@cold:~/ros_gz_ws$ ros2 topic list
/parameter_events
/ros_chatter
/rosout

Confirm that no container has been created:

caguero@cold:~/ros_gz_ws$ ros2 component list

Now CTRL-C to stop all nodes and try the composable version:

ros2 launch ros_gz_sim ros_gz_sim.launch.py world_sdf_file:=empty.sdf use_composition:=True config_file:=/home/caguero/ros_gz_ws/src/ros_gz/ros_gz_bridge/test/config/full.yaml

gzserver should be running. Verify that you also see the /ros_chatter topic:

caguero@cold:~/ros_gz_ws$ ros2 topic list
/parameter_events
/ros_chatter
/rosout

And confirm that a container has been created with both nodes:

caguero@cold:~/ros_gz_ws$ ros2 component list
/ros_gz_container
  1  /ros_gz_bridge
  2  /gzserver

Test it

Checklist

• Signed all commits for DCO
• Added tests
• Added example and/or tutorial
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• While waiting for a review on your PR, please help review another open pull request to support the maintainers

Note to maintainers: Remember to use Squash-Merge and edit the commit message to match the pull request summary while retaining Signed-off-by messages.

[azeey]

I imagine we'll have a log_level parameter for gz_sever as well at some point. How would we distinguish parameters for the server and parameters for the bridge? Should we rename this to bridge_log_level?

[caguero]

Renamed in 66e74f8

[azeey]

Any luck with refactoring these into a separate Python module so we don't have to duplicate code?

[caguero]

Any luck with refactoring these into a separate Python module so we don't have to duplicate code?

Apparently this is possible by creating a separate launch file for the common parts. I'll do it in a separate PR.

[caguero]

@ahcorde, is CI supposed to pass right now with 24.04?

[ahcorde]

@caguero yes, I think it should pass