Cpp code genrators for ROS2 nodes

[ipa-nhg]

These changes creates for the RosModel model:

PackageSet { 
	CatkinPackage test_ros2{ Artifact  test_ros2 {
	  Node { name test_ros2 
		Publishers {
			Publisher { name string_pub message "std_msgs.String"},
			Publisher { name battery_pub message "sensor_msgs.BatteryState"}}
		Subscribers {
			Subscriber {name bool_sub message "std_msgs.Bool"},
			Subscriber {name image_sub message "sensor_msgs.Image"}}
		}
	}}}

the following ROS package:

https://github.com/ipa-nhg/test_ros2_code_extractor/tree/master/test_ros2

To test it I used the ros-model-extractors and its foxy docker container with the commands:

docker build --tag=haros_foxy -f foxy/Dockerfile .
docker run -it haros_foxy:latest /haros_runner.sh test_ros2 test_ros2 node . /root/ws https://github.com/ipa-nhg/test_ros2_code_extractor

The resulted model was:

## Init HAROS ##
[HAROS] Running setup operations...

## Call the HAROS plugin to extract the ros-models ##
###########
~~~~~~~~~~~
Print of the model: test_ros2.ros:
~~~~~~~~~~~
PackageSet {
  CatkinPackage test_ros2 { 
    Artifact test_ros2 {
      Node { name test_ros2
        Publishers {
          Publisher { name 'string_pub' message 'std_msgsString'},
          Publisher { name 'battery_pub' message 'sensor_msgsBatteryState'}}
        Subscribers {
          Subscriber { name 'bool_sub' message 'std_msgsBool'},
          Subscriber { name 'image_sub' message 'sensor_msgsImage'}}}}
}}
~~~~~~~~~~~
###########

[ipa-nhg]

Comments from @ipa-hsd of potential improvements for the code template:

• I would avoid having a main() in the node cpp. maybe a separate main.cpp with all the nodes in that package are added to executor. (this would be just an example). https://github.com/ros2/examples/blob/master/rclcpp/executors/multithreaded_executor/multithreaded_executor.cpp#L167-L175
• Instead use nodes as components: https://github.com/ros2/demos/blob/master/composition/src/listener_component.cpp#L55
  this will give and option to load nodes as components (available only for rclcpp)
  https://docs.ros.org/en/foxy/Tutorials/Composition.html
• Quality attributes can be used for Qos? This one uses only history QoS (with default 10)
  https://github.com/ipa320/ros-model/blob/master/plugins/de.fraunhofer.ipa.roscode.generator/src/de/fraunhofer/ipa/roscode/generator/Ros2CodeGenerator.xtend#L74
  Example: https://github.com/ros2/demos/blob/master/image_tools/src/cam2image.cpp#L65-L81
  https://github.com/ros2/demos/blob/master/image_tools/src/cam2image.cpp#L65-L81
• Parameters and actions are missed

[hsd-dev]

rclcpp is missing I think

[ipa-nhg]

updated to add rclcpp 76dc766#diff-d93fff18e9ce55d7368dd228b37f783b3a3821a4e16da3885bb636a29a43819eR97

[ipa-nhg]

I updated here also the ROS1 code generator to generate also a full package.

For testing I added the autogenerated example to: https://github.com/ipa-nhg/test_ros_code_extractor and I am using the cpp code that we are generating to test the extractors: ipa320/ros-model-extractors@dbfc5a6#diff-3722d9ba8feb2d3feac8ce71a209a638d4b404e1c53f937188761181594023e2R23

All the tests are successful: https://github.com/ipa320/ros-model-extractors/actions 👏🏽 👏🏽

@ipa-hsd thanks for your help! should we merge this version and continue the improvements of the ROS2 code generation in #135 ?

[hsd-dev]

LGTM let's merge this one!