Following

[ajtudela]

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Basic Info

Info	Please fill out this column
Ticket(s) this addresses
Primary OS tested on	Ubuntu 24.04
Robotic platform tested on	Morphia
Does this PR contain AI generated software?	Nope
Was this PR description generated by AI software?	Out of respect for maintainers, AI for human-to-human communications are banned

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Description of contribution in a few bullet points

This PR introduces a new following_server, which provides a dynamic object-following task server.

Description of documentation updates required from your changes

• New configuration and migration docs its needed.

Description of how this change was tested

• I wrote unit tests that cover ~90% of changes and tested on my physical robot.
• Performed linting validation using pre-commit run --all or colcon test

---

Future work that may be required in bullet points

For Maintainers:

• Check that any new parameters added are updated in docs.nav2.org
• Check that any significant change is added to the migration guide
• Check that any new features OR changes to existing behaviors are reflected in the tuning guide
• Check that any new functions have Doxygen added
• Check that any new features have test coverage
• Check that any new plugins is added to the plugins page
• If BT Node, Additionally: add to BT's XML index of nodes for groot, BT package's readme table, and BT library lists
• Should this be backported to current distributions? If so, tag with backport-*.

[mergify]

@ajtudela, your PR has failed to build. Please check CI outputs and resolve issues.
You may need to rebase or pull in main due to API changes (or your contribution genuinely fails).

[ajtudela]

I'm not sure why the build failed :S

[SteveMacenski]

Starting >>> opennav_following
[3407.392s] ERROR:colcon.colcon_cmake.task.cmake.build:Failed to find the following files:
- /opt/overlay_ws/install/opennav_docking_core/share/opennav_docking_core/package.sh
- /opt/overlay_ws/install/opennav_docking/share/opennav_docking/package.sh
Check that the following packages have been built:
- opennav_docking_core
- opennav_docking
Failed   <<< opennav_following [0.01s, exited with code 1]

Perhaps these are missing from the following server's package xml?

[SteveMacenski]

Oh I see, add the package(s) to https://github.com/ros-navigation/navigation2/blob/main/.circleci/config.yml#L535 regex list (we split the build jobs into 2 now because we have so much fucking code now)

[SteveMacenski]

Also, adding the Python API to call the Following Server would be nice! As well as bringup using Nav2 Bringup's navigation.launch.py so its out-of-the-box

[ajtudela]

I have a problem with mypy I can't fix:

nav2_simple_commander/nav2_simple_commander/robot_navigator.py: note: In member "__init__" of class "BasicNavigator":
nav2_simple_commander/nav2_simple_commander/robot_navigator.py:110: error: Name "NavigateThroughPoses.Goal" is not defined  [name-defined]
nav2_simple_commander/nav2_simple_commander/robot_navigator.py:110: error: Name "NavigateThroughPoses.Result" is not defined  [name-defined]
nav2_simple_commander/nav2_simple_commander/robot_navigator.py:110: error: Name "NavigateThroughPoses.Feedback" is not defined  [name-defined

Using the line '# type: ignore[name-defined]' passes the pre-commit, but an error is shown in the build.

[SteveMacenski]

@leander-dsouza can you look at the linting issue? Can this static analysis be lightened up? I think we're hitting a point that its more a bother than a help

[SteveMacenski]

@ajtudela you have a couple of tests failing in appear to look like real ways as part of the test python code

[SteveMacenski]

One more thing... Add the error code prefix default to bt_action_server_impl.hpp as well as in the nav2_params.yaml so the following error codes are considered

  std::vector<std::string> error_code_name_prefixes = {
    "assisted_teleop",
    "backup",
    "compute_path",
    "dock_robot",
    "drive_on_heading",
    "follow_path",
    "nav_thru_poses",
    "nav_to_pose",
    "spin",
    "undock_robot",
    "wait",
  };

[leander-dsouza]

@leander-dsouza can you look at the linting issue? Can this static analysis be lightened up? I think we're hitting a point that its more a bother than a help

Yes, I'll make a PR shortly to fix all the ament_mypy issues.
I think we can drop the --strict flag henceforth if the CI fails again.

[ajtudela]

@ajtudela you have a couple of tests failing in appear to look like real ways as part of the test python code

I fixed the tests but the CI fail in other tests, I think...

[SteveMacenski]

@ajtudela can you pull in main? We have CI green again so anything failing after that point should be things only from this PR. the speed/keepout are something in CI that was fixed. The error codes I think may actually be real given this PR's changes (but TBD)

[ajtudela]

Everything is working now, except for mypy.

Also, it seems that the code coverage is looking for the old opennav_following_bt files.

[SteveMacenski]

Ah, that'll happen. Update the v39 to v40 in the 3 places within this highlighted block and that should be fixed: https://github.com/ros-navigation/navigation2/blob/main/.circleci/config.yml#L36-L61

[SteveMacenski]

Make sure to add them here: https://github.com/ros-navigation/navigation2/blob/main/navigation2/package.xml so they're part of the nav2 metapackage for installation!

[mergify]

@ajtudela, your PR has failed to build. Please check CI outputs and resolve issues.
You may need to rebase or pull in main due to API changes (or your contribution genuinely fails).

[mergify]

This pull request is in conflict. Could you fix it @ajtudela?

[SteveMacenski]

@ajtudela I think just getting CI to turn over and the merge conflict is all that's needed to merge!

[SteveMacenski]

Retriggering CI, if it doesn't build when I look tomorrow I'll investigate more. Seems like a timing issue

Though mypy has one pedantic real issue left:

Error: nav2_simple_commander/nav2_simple_commander/robot_navigator.py:27:1: error: Module "nav2_msgs.action" has no attribute "FollowObject" [attr-defined]

[mergify]

@ajtudela, your PR has failed to build. Please check CI outputs and resolve issues.
You may need to rebase or pull in main due to API changes (or your contribution genuinely fails).

[mergify]

@ajtudela, your PR has failed to build. Please check CI outputs and resolve issues.
You may need to rebase or pull in main due to API changes (or your contribution genuinely fails).