Hi Bojan,

Dear Sirs,

I have a hard time to cross-compile and to properly include the custom ROS2 foxy package into the Yocto image. I properly added meta-ros layer and ROS2 foxy distro to our Yocto build by following instructions from here (Sanity Tests pass successfully).

I wanted to use a devtool and build a simple custom ROS2 package containing publisher and subscriber nodes. The source code of the package is on the git - link.

I used tips and tricks from here to create ROS2 recipes with the devtool. My custom bitbake recipe for the simple ROS2 package looks like this (my-first-yocto-pkg_git.bb file):

DESCRIPTION = "Example of minimal publisher/subscriber using rclcpp."
LICENSE = "Apache-2.0"
LIC_FILES_CHKSUM = "file://package.xml;beginline=8;endline=8;md5=3a75fd635766e2f76c3d90ee6495f310"

SRC_URI = "git://github.com/bojankoce/ros2pkg;protocol=https"

# Modify these as desired
PV = "0.1.0"
SRCREV = "1312445de2e6861d9561c0f89f4827b94c2ff6b1"

DEPENDS = "rclcpp std-msgs"

S = "${WORKDIR}/git"

# NOTE: unable to map the following CMake package dependencies: rclcpp ament_lint_auto std_msgs ros_ament_cmake
inherit ros_ament_cmake

However, when I tried to build the package with the devtool build my-first-yocto-pkg command, I get the following error:

CMake Error at CMakeLists.txt:19 (find_package):
  By not providing "Findament_cmake.cmake" in CMAKE_MODULE_PATH this project
  has asked CMake to find a package configuration file provided by
  "ament_cmake", but CMake did not find one.

  Could not find a package configuration file provided by "ament_cmake" with
  any of the following names:

    ament_cmakeConfig.cmake
    ament_cmake-config.cmake

  Add the installation prefix of "ament_cmake" to CMAKE_PREFIX_PATH or set
  "ament_cmake_DIR" to a directory containing one of the above files.  If
  "ament_cmake" provides a separate development package or SDK, be sure it
  has been installed.

The issue is around ament_cmake. I included the inherit ros_ament_cmake line into the recipe but this does not help. Do you have any idea about what I am missing here? Is there any better way to cross-compile and include a custom ROS2 foxy package into the Yocto image?

You are missing a DEPENDS, ros_ament_cmake does not add it. Try adding ament-cmake-native to your DEPENDS and see if that works (or give you a different error message, since I guess you might be missing out more stuff).

Regards,

   Matthias