记录一个ROS2 colcon编译时的bug

本教程作者：小鱼 公众号：鱼香ROS QQ交流群：139707339 教学视频地址：小鱼的B站 官网：鱼香ROS官网 版权声明：如非允许禁止转载与商业用途。

一、核心错误

  File "/opt/ros/foxy/lib/python3.8/site-packages/rosidl_parser/parser.py", line 20, in 
    from lark import Lark
ModuleNotFoundError: No module named 'lark'

二、解决方法

pipi install  lark

三、原始报错

root@d4864f4ccde3:~/code/turtlebot3_ws# colcon build --packages-select turtlebot3_msgs
Starting >>> turtlebot3_msgs
--- stderr: turtlebot3_msgs                            
Traceback (most recent call last):
  File "/opt/ros/foxy/share/rosidl_generator_c/cmake/../../../lib/rosidl_generator_c/rosidl_generator_c", line 8, in 
    from rosidl_generator_c import generate_c
  File "/opt/ros/foxy/lib/python3.8/site-packages/rosidl_generator_c/__init__.py", line 15, in 
    from rosidl_cmake import convert_camel_case_to_lower_case_underscore
  File "/opt/ros/foxy/lib/python3.8/site-packages/rosidl_cmake/__init__.py", line 24, in 
    from rosidl_parser.parser import parse_idl_file
  File "/opt/ros/foxy/lib/python3.8/site-packages/rosidl_parser/parser.py", line 20, in 
    from lark import Lark
ModuleNotFoundError: No module named 'lark'
make[2]: *** [CMakeFiles/turtlebot3_msgs__rosidl_generator_c.dir/build.make:117: rosidl_generator_c/turtlebot3_msgs/msg/sensor_state.h] Error 1
make[1]: *** [CMakeFiles/Makefile2:300: CMakeFiles/turtlebot3_msgs__rosidl_generator_c.dir/all] Error 2
make[1]: *** Waiting for unfinished jobs....
Traceback (most recent call last):
  File "/opt/ros/foxy/share/rosidl_generator_cpp/cmake/../../../lib/rosidl_generator_cpp/rosidl_generator_cpp", line 8, in 
    from rosidl_generator_cpp import generate_cpp
  File "/opt/ros/foxy/lib/python3.8/site-packages/rosidl_generator_cpp/__init__.py", line 17, in 
    from rosidl_cmake import generate_files
  File "/opt/ros/foxy/lib/python3.8/site-packages/rosidl_cmake/__init__.py", line 24, in 
    from rosidl_parser.parser import parse_idl_file
  File "/opt/ros/foxy/lib/python3.8/site-packages/rosidl_parser/parser.py", line 20, in 
    from lark import Lark
ModuleNotFoundError: No module named 'lark'
make[2]: *** [CMakeFiles/turtlebot3_msgs__cpp.dir/build.make:141: rosidl_generator_cpp/turtlebot3_msgs/msg/sensor_state.hpp] Error 1
make[1]: *** [CMakeFiles/Makefile2:409: CMakeFiles/turtlebot3_msgs__cpp.dir/all] Error 2
make: *** [Makefile:141: all] Error 2
---
Failed