Error in ros2genmsg (line 467) buildPackage(builder, [], ' --merge-install', colconMakeArgs);

I received this error when using the ros2genmsg function (the image shows the structure of the folder containing the action interface, I was currently in the folder "ros2CustomMessages":

>> ros2genmsg(pwd)

Identifying message files in folder 'C:/Studium/TUM/Master/2. Semester/MTT Tutor/ROS2Interface/ros2CustomMessages'..Validating message files in folder 'C:/Studium/TUM/Master/2. Semester/MTT Tutor/ROS2Interface/ros2CustomMessages'..Done.

Done.

[1/1] Generating MATLAB interfaces for custom message packages... Done.

Running colcon build in folder 'C:/Studium/TUM/Master/2. Semester/MTT Tutor/ROS2Interface/ros2CustomMessages/matlab_msg_gen/win64'.

Build in progress. This may take several minutes...Error using ros.internal.ROSProjectBuilder/buildPackage

Error building package: build_log.

Error in ros2genmsg (line 467)

buildPackage(builder, [], ' --merge-install', colconMakeArgs);

The build_log said the following:

Traceback (most recent call last): File "C:/Program Files/MATLAB/R2023b/sys/ros2/win64/ros2/share/ament_cmake_core/cmake/core/package_xml_2_cmake.py", line 150, in <module> main() File "C:/Program Files/MATLAB/R2023b/sys/ros2/win64/ros2/share/ament_cmake_core/cmake/core/package_xml_2_cmake.py", line 53, in main raise e File "C:/Program Files/MATLAB/R2023b/sys/ros2/win64/ros2/share/ament_cmake_core/cmake/core/package_xml_2_cmake.py", line 49, in main package = parse_package_string( ^^^^^^^^^^^^^^^^^^^^^ File "C:\Users\paqua\AppData\Roaming\MathWorks\MATLAB\R2023b\ros2\win64\venv\lib\site-packages\catkin_pkg\package.py", line 788, in parse_package_string pkg.validate(warnings=warnings) File "C:\Users\paqua\AppData\Roaming\MathWorks\MATLAB\R2023b\ros2\win64\venv\lib\site-packages\catkin_pkg\package.py", line 330, in validate raise InvalidPackage('\n'.join(errors), self.filename) catkin_pkg.package.InvalidPackage: Error(s) in package 'C:/Studium/TUM/Master/2. Semester/MTT Tutor/ROS2Interface/ros2CustomMessages/matlab_msg_gen/win64/src/action_msgs/package.xml': The package "action_msgs" must not "build_depend" on a package with the same name as this package The package "action_msgs" must not "build_export_depend" on a package with the same name as this package The package "action_msgs" must not "exec_depend" on a package with the same name as this package

Answer 1

[Josh Chen]

Hi Quan,

As the build log message mentioned, the culprit is that the package name of your custom message is "action_msgs", which is exactly the same as one of the ROS(2) Package that any custom message generation for action requires (See this page for the "action_msgs" package). Hence, during the code generation process, CMake got confused.

To address this issue, please rename your package to another name.

e.g. change the folder "action_msgs" to "my_action_msgs".

Hope this helps,

Thanks,

Josh