Bug: Unable to Get Model Pose Info When publish_model_pose Is Set to True in Gazebo Harmonic

[Kametor]

Environment

• OS Version: Ubuntu 22.04
• Source or binary build: Binary build (Gazebo Harmonic)

Description

• Expected behavior:
  I am trying to get the model position info with respect to the Gazebo world frame. Based on my understanding, the pose publisher system should be used for this purpose. However, when I call the system with the publish_model_pose parameter set to true, I am unable to get the pose information. I checked it using the command:
  gz topic -e -t "topic name"
  After examining the source code of the system, I noticed that the publish_model_pose parameter is not being used. Instead, the publish_nested_model parameter is being checked, and it is set to false by default. When I changed the publish_nested_model parameter to true, I was successfully able to get the model pose information.
  It seems that the nested_model_pose is used when there is no model_pose parameter. However, there doesn't appear to be a conditional check for this in the code. I believe this condition may be missing and could be causing the issue.

• Actual behavior:
  The model pose is not publishing unless you set True for publish_nested_model_pose

Steps to reproduce

1. Use pose publisher system in a basic gazebo world.
2. Set the publish_model_pose parameter to true.
3. Try to get the model pose information via the appropriate topic.
4. Observe that no pose information is received.
5. Change the publish_nested_model parameter to true to successfully retrieve the model pose info.

Output

Using pose publisher system with correct parameters

The missing if condition part in code

[iche033]

fixed in #2697, will backport to harmonic once merged.