ros2 module_error ai_generated true

[component_container_isolated]: Failed to load component: Failed to find class with name 'my_pkg::MyComponent': No matching class found in library

ID: ros2/component-container-mismatch

Also available as: JSON · Markdown · 中文
90%Fix Rate
87%Confidence
1Evidence
2023-06-22First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
ROS2 Humble active — — —
ROS2 Iron active — — —
ROS2 Jazzy active — — —

Root Cause

The component class is either not registered with the RCLCPP_COMPONENTS_REGISTER_NODE macro, or the library was not built/linked correctly, so the container cannot instantiate it at runtime.

generic

中文

组件类未使用RCLCPP_COMPONENTS_REGISTER_NODE宏注册，或者库未正确构建/链接，导致容器在运行时无法实例化它。

Official Documentation

https://docs.ros.org/en/humble/Tutorials/Intermediate/Composition.html

Workarounds

  1. 95% success Ensure the component source file includes the registration macro: 'RCLCPP_COMPONENTS_REGISTER_NODE(my_pkg::MyComponent)' and that the CMakeLists.txt uses 'add_library' with 'ament_target_dependencies' and 'pluginlib_export_plugin_description_file' if needed. 
    Ensure the component source file includes the registration macro: 'RCLCPP_COMPONENTS_REGISTER_NODE(my_pkg::MyComponent)' and that the CMakeLists.txt uses 'add_library' with 'ament_target_dependencies' and 'pluginlib_export_plugin_description_file' if needed.
  2. 85% success Check the library exports: 'nm -C libmy_component.so | grep MyComponent' to see if the symbol is present. If not, rebuild with 'colcon build --cmake-args -DCMAKE_BUILD_TYPE=Debug' and check for missing dependencies. 
    Check the library exports: 'nm -C libmy_component.so | grep MyComponent' to see if the symbol is present. If not, rebuild with 'colcon build --cmake-args -DCMAKE_BUILD_TYPE=Debug' and check for missing dependencies.
  3. 90% success Verify the component's plugin description XML file (e.g., 'my_component_plugins.xml') is correctly formatted and referenced in 'package.xml' under <export>. 
    Verify the component's plugin description XML file (e.g., 'my_component_plugins.xml') is correctly formatted and referenced in 'package.xml' under <export>.

中文步骤

  1. 确保组件源文件包含注册宏：'RCLCPP_COMPONENTS_REGISTER_NODE(my_pkg::MyComponent)'，并且CMakeLists.txt使用'add_library'，必要时包含'ament_target_dependencies'和'pluginlib_export_plugin_description_file'。
  2. 检查库导出：'nm -C libmy_component.so | grep MyComponent'以查看符号是否存在。如果不存在，使用'colcon build --cmake-args -DCMAKE_BUILD_TYPE=Debug'重新构建并检查缺失的依赖。
  3. 验证组件的插件描述XML文件（如'my_component_plugins.xml'）格式正确，并在'package.xml'的<export>部分中引用。

Dead Ends

Common approaches that don't work:

  1. Adding the component source file to a different package's CMakeLists.txt without proper registration 90% fail

    The class must be registered in the same library where it is built, using the correct macro. Moving files without registration does not help.

  2. Manually loading the library with 'dlopen' in the container to verify it exists 60% fail

    The library may exist but the class registration may still be missing. This does not fix the registration issue.