ros_ign_gazebo- ign_args launch arg not respected in ign_gazebo.launch.py

[mwcondino]

Environment

• OS Version: Ubuntu 22.04
• Source or binary build?
  ros-humble-ros-ign-gazebo at 0.244.6-1jammy.20220916.172640
libignition-gazebo6:amd64 at 6.12.0-1~jammy

Description

It looks like the ign_gazebo.launch.py launch file may not respect ign_args in a humble environment with Ignition Fortress installed.

Steps to reproduce

1. Ensure ros-humble-ros-ign-gazebo is installed
2. Try running a gazebo session headless through the launch file:

ros2 launch ros_ign_gazebo ign_gazebo.launch.py ign_args:="-s"

3. You should see a gui pop up after this - this indicates the ign_args parameter is not set.

Workaround

Using gz_args instead of ign_args appears to be working. In addition, I think if you force the ignition version like this....

ros2 launch ros_ign_gazebo ign_gazebo.launch.py ign_args:="-s" ign_version:=6

the bug is no longer evident.

It's probably best to update launch files to use gz_args as a fix here, since that is more future facing and ign_* args are deprecated.

[mjcarroll]

@mwcondino please look at #309 and see if this resolves the issue.

[mjcarroll]

It's probably best to update launch files to use gz_args as a fix here, since that is more future facing and ign_* args are deprecated.

This is ideal long-term, but there should be some middle ground with deprecation warnings, that is what I have implemented.

[mjcarroll]

#309 has been released to humble and will be available in the next sync. If this doesn't resolve it, please feel free to reopen.

[mwcondino]

Thanks @mjcarroll, that fix looks good to me!