rosidl_adapter/cmake/rosidl_adapt_interfaces.cmake: Make ament free

[yashi]

The module FindPython3 already provides the interpreter executable path via Python3_EXECUTABLE. No need to use ament.

Less loaded module means faster execution. And easier for out of tree build system to reuse this function.

Signed-off-by: Yasushi SHOJI yashi@spacecubics.com

[aditya2592]

Hi, thanks for raising this PR. Can it be merged and backported to humble? We are having issues with building ROS2 on top of a custom python installation because of this line get_executable_path(python_interpreter Python3::Interpreter CONFIGURE) which is removed in this PR

[yashi]

Hi, I'm not clear what I'm asked to do. The PR is obviously not merged. But are you trying to use it on Humble? Am I asked to test it or port it on Humble? How can I reproduce the problem you are seeing here?

[aditya2592]

I think I just wanted to ask in general how to get this merged. Do you know the maintainers for this repo at all? Maybe we could tag them?

[aditya2592]

@clalancette could you help us figure out what we need to do in order to get this PR merged? It would help us in our project

[sloretz]

We are having issues with building ROS2 on top of a custom python installation because of this line get_executable_path(python_interpreter Python3::Interpreter CONFIGURE) which is removed in this PR

@aditya2592 This PR is getting the path to the Python interpreter from FindPython3 with one less step, but I would not expect a difference in the path returned. That is I would assume the path returned by get_executable_path(... Python3::Interpreter CONFIGURE) is always the same as Python3_EXECUTABLE. If your build is finding the wrong version of python then this PR is probably not going to fix it. The solution you're probably looking for are the HINT variables use by the FindPython3 module.

[sloretz]

LGTM with full CI

[sloretz]

And easier for out of tree build system to reuse this function.

@yashi if you're looking to convert .msg, .srv, or .action files to .idl without using ament_cmake then I'd recommend the rosidl translate command.

Here's a quick manual example:

sloretz@rolling-jammy:~$ cd /opt/ros/rolling/share/
sloretz@rolling-jammy:/opt/ros/rolling/share$ rosidl translate --to idl sensor_msgs std_msgs/msg/Header.msg -o /tmp/
Reading input file: /opt/ros/rolling/share/std_msgs/msg/Header.msg
Writing output file: /tmp/std_msgs/msg/Header.idl
sloretz@rolling-jammy:/opt/ros/rolling/share$ cat /tmp/std_msgs/msg/Header.idl 
// generated from rosidl_adapter/resource/msg.idl.em
// with input from sensor_msgs/std_msgs/msg/Header.msg
// generated code does not contain a copyright notice

#include "builtin_interfaces/msg/Time.idl"

module sensor_msgs {
  module msg {
    @verbatim (language="comment", text=
      "Standard metadata for higher-level stamped data types." "\n"
      "This is generally used to communicate timestamped data" "\n"
      "in a particular coordinate frame.")
    struct Header {
      @verbatim (language="comment", text=
        "Two-integer timestamp that is expressed as seconds and nanoseconds.")
      builtin_interfaces::msg::Time stamp;

      @verbatim (language="comment", text=
        "Transform frame with which this data is associated.")
      string frame_id;
    };
  };
};

For a real example, see how it's used to build ROS 2 interfaces with bazel: There's an example that uses it for building interfaces with bazel here: https://github.com/RobotLocomotion/drake-ros/blob/7c1429806547dadc7209f3784eecf3cf5106c45f/bazel_ros2_rules/ros2/rosidl.bzl#L117

[sloretz]

CI (repos file build: everything test: everything)

• Linux
• Linux-aarch64
• Windows

[adityapande-1995]

CI can't find service_msgs on jammy it seems ?

[clalancette]

CI can't find service_msgs on jammy it seems ?

For the Rpr job, yeah, that is going to be the case currently. We need to do a round of releases on Rolling (hopefully this week).