Copy nav2 launch file from rolling branch

with added headless LaunchConfiguration
as this hasn't been back ported to  humble
- ros-navigation/navigation2#3527

.dockerignore

@@ -6,3 +6,6 @@
 # Files
 .dockerignore
 .gitignore
+
+# Python
+__pycache__/

.gitignore

@@ -1,2 +1,5 @@
 # Visual Studio Code files
 .vscode
+
+# Python
+__pycache__/

launch/security_demo_launch.py

@@ -0,0 +1,98 @@
+# Copyright (c) 2021 Samsung Research America
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import os
+
+from ament_index_python.packages import get_package_share_directory
+
+from launch import LaunchDescription
+from launch.actions import DeclareLaunchArgument, ExecuteProcess, IncludeLaunchDescription
+from launch.conditions import IfCondition
+from launch.launch_description_sources import PythonLaunchDescriptionSource
+from launch.substitutions import LaunchConfiguration, PythonExpression
+from launch_ros.actions import Node
+
+
+def generate_launch_description():
+    warehouse_dir = get_package_share_directory('aws_robomaker_small_warehouse_world')
+    nav2_bringup_dir = get_package_share_directory('nav2_bringup')
+    python_commander_dir = get_package_share_directory('nav2_simple_commander')
+
+    map_yaml_file = os.path.join(warehouse_dir, 'maps', '005', 'map.yaml')
+    world = os.path.join(python_commander_dir, 'warehouse.world')
+
+    # Launch configuration variables
+    use_rviz = LaunchConfiguration('use_rviz')
+    headless = LaunchConfiguration('headless')
+
+    # Declare the launch arguments
+    declare_use_rviz_cmd = DeclareLaunchArgument(
+        'use_rviz',
+        default_value='True',
+        description='Whether to start RVIZ')
+
+    declare_simulator_cmd = DeclareLaunchArgument(
+        'headless',
+        default_value='False',
+        description='Whether to execute gzclient)')
+
+    # start the simulation
+    start_gazebo_server_cmd = ExecuteProcess(
+        cmd=['gzserver', '-s', 'libgazebo_ros_factory.so', world],
+        cwd=[warehouse_dir], output='screen')
+
+    start_gazebo_client_cmd = ExecuteProcess(
+        condition=IfCondition(PythonExpression(['not ', headless])),
+        cmd=['gzclient'],
+        cwd=[warehouse_dir], output='screen')
+
+    urdf = os.path.join(nav2_bringup_dir, 'urdf', 'turtlebot3_waffle.urdf')
+    start_robot_state_publisher_cmd = Node(
+        package='robot_state_publisher',
+        executable='robot_state_publisher',
+        name='robot_state_publisher',
+        output='screen',
+        arguments=[urdf])
+
+    # start the visualization
+    rviz_cmd = IncludeLaunchDescription(
+        PythonLaunchDescriptionSource(
+            os.path.join(nav2_bringup_dir, 'launch', 'rviz_launch.py')),
+        condition=IfCondition(use_rviz),
+        launch_arguments={'namespace': '',
+                          'use_namespace': 'False'}.items())
+
+    # start navigation
+    bringup_cmd = IncludeLaunchDescription(
+        PythonLaunchDescriptionSource(
+            os.path.join(nav2_bringup_dir, 'launch', 'bringup_launch.py')),
+        launch_arguments={'map': map_yaml_file}.items())
+
+    # start the demo autonomy task
+    demo_cmd = Node(
+        package='nav2_simple_commander',
+        executable='demo_security',
+        emulate_tty=True,
+        output='screen')
+
+    ld = LaunchDescription()
+    ld.add_action(declare_use_rviz_cmd)
+    ld.add_action(declare_simulator_cmd)
+    ld.add_action(start_gazebo_server_cmd)
+    ld.add_action(start_gazebo_client_cmd)
+    ld.add_action(start_robot_state_publisher_cmd)
+    ld.add_action(rviz_cmd)
+    ld.add_action(bringup_cmd)
+    ld.add_action(demo_cmd)
+    return ld