[ros2] Port spawn model to ROS2

gazebo_ros/CMakeLists.txt

@@ -129,6 +129,12 @@ install(
   LIBRARY DESTINATION lib
   RUNTIME DESTINATION bin)
 
+install(
+  PROGRAMS
+    scripts/spawn_entity.py
+    DESTINATION lib/${PROJECT_NAME}/
+)
+
 install(DIRECTORY
   launch
   DESTINATION share/${PROJECT_NAME}/

gazebo_ros/launch/spawn_entity_demo.launch.py

@@ -0,0 +1,42 @@
+# Copyright 2019 Open Source Robotics Foundation, Inc.
+#
+# 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.
+
+"""
+Demo for spawn_entity.
+
+Launches Gazebo and spawns a model
+"""
+
+from launch import LaunchDescription
+from launch.actions import IncludeLaunchDescription
+from launch.launch_description_sources import PythonLaunchDescriptionSource
+from launch.substitutions import ThisLaunchFileDir
+from launch_ros.actions import Node
+
+
+def generate_launch_description():
+    gazebo = IncludeLaunchDescription(
+                PythonLaunchDescriptionSource([ThisLaunchFileDir(), '/gazebo.launch.py']),
+             )
+
+    # GAZEBO_MODEL_PATH has to be correctly set for Gazebo to be able to find the model
+    spawn_entity = Node(package='gazebo_ros', node_executable='spawn_entity.py',
+                        arguments=['-entity', 'demo', '-database', 'double_pendulum_with_base'],
+                        output='screen')
+
+    return LaunchDescription([
+        gazebo,
+
+        spawn_entity,
+    ])

gazebo_ros/package.xml

@@ -25,6 +25,7 @@
   <depend>gazebo_dev</depend>
   <depend>gazebo_msgs</depend>
   <depend>rclcpp</depend>
+  <depend>rclpy</depend>
   <depend>std_srvs</depend>
   <depend>tinyxml_vendor</depend>