Can we include launch file descriptions that are written in some other langauge?

asked 2022-01-25 02:06:43 -0600

Raza Rizvi
95 ●3 ●9 ●15

Is there a possibility to include launch file description written in, for example, XML or YAML, into a launch file description written in Python?

For example, doing something like this in a Python launch file description?

def generate_launch_description():

   turtlesim_world_1 = IncludeLaunchDescription(
      PythonLaunchDescriptionSource([os.path.join(
         get_package_share_directory('launch_tutorial'), 'launch'),
         '/turtlesim_world_1.xml'])
      )

   return LaunchDescription([
      turtlesim_world_1,
   ])

answered 2022-04-12 13:49:30 -0600

omers
1 ●1 ●1

Hi,

So after digging into the source code a little, I found there is a FrontendLaunchDescriptionSource class that can be used to include .yaml/.xml files inside a python launch file, example:

import os
from launch import LaunchDescription
from launch.launch_description_sources import FrontendLaunchDescriptionSource
from launch_ros.actions import Node
from launch.actions import IncludeLaunchDescription
from ament_index_python.packages import get_package_share_directory

def generate_launch_description():
  return LaunchDescription([      
    Node(
        package='turtlesim',
        executable='mimic',
        name='mimic',
        remappings=[
            ('/input/pose', '/turtlesim1/turtle1/pose'),
            ('/output/cmd_vel', '/turtlesim2/turtle1/cmd_vel'),
        ]
    ),
    IncludeLaunchDescription(
        FrontendLaunchDescriptionSource(os.path.join(get_package_share_directory('rosbridge_server'), 'launch', 'rosbridge_websocket_launch.xml'))
    ),
  ])