Merge pull request #4 from ros-controls/initial_pkg_structure

Add initial package structure

.clang-format

+---
+Language:        Cpp
+BasedOnStyle:  Google
+...

.github/workflows/ci.yml

+name: CI
+on:
+  pull_request:
+  push:
+    branches:
+      - master
+  schedule:
+    # Run every morning to detect flakiness and broken dependencies
+    - cron: '28 6 * * *'
+
+jobs:
+  industrial_ci:
+    strategy:
+      matrix:
+        env:
+          - {ROS_DISTRO: foxy, ROS_REPO: testing}
+          - {ROS_DISTRO: foxy, ROS_REPO: main}
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v1
+      - uses: 'ros-industrial/industrial_ci@master'
+        env: ${{matrix.env}}

.github/workflows/code_coverage.yml

+name: Coverage
+on:
+  pull_request:
+  push:
+    branches:
+      - master
+  schedule:
+    # Run every morning to detect flakiness and broken dependencies
+    - cron: '17 8 * * *'
+
+jobs:
+  build_and_test:
+    runs-on: ubuntu-18.04
+    strategy:
+      fail-fast: false
+    steps:
+      - uses: ros-tooling/setup-ros@0.0.13
+      - uses: ros-tooling/action-ros-ci@0.0.13
+        with:
+          package-name: ros2_control_demo_communication_gazebo ros2_control_demo_communication_headless ros2_control_demo_hardware ros2_control_demo_robot
+          colcon-mixin-name: coverage-gcc
+          colcon-mixin-repository: https://raw.githubusercontent.com/colcon/colcon-mixin-repository/master/index.yaml
+      - uses: codecov/codecov-action@v1
+        with:
+          token: ${{ secrets.CODECOV_TOKEN }}
+          file: ros_ws/lcov/total_coverage.info
+          flags: unittests
+          name: codecov-umbrella
+          yml: ./codecov.yml
+          fail_ci_if_error: true
+#      - uses: actions/upload-artifact@master
+#        with:
+#          name: colcon-logs-${{ matrix.os }}
+#          path: ros_ws/log

.github/workflows/linters.yaml

+name: Linters
+on:
+  pull_request:
+
+jobs:
+  ament_copyright:
+    name: ament_copyright
+    runs-on: ubuntu-18.04
+    steps:
+    - uses: actions/checkout@v1
+    - uses: ros-tooling/setup-ros@0.0.13
+    - uses: ros-tooling/action-ros-lint@0.0.5
+      with:
+        linter: copyright
+        package-name: ros2_control_demo_communication_gazebo ros2_control_demo_communication_headless ros2_control_demo_hardware ros2_control_demo_robot
+
+  ament_xmllint:
+    name: ament_xmllint
+    runs-on: ubuntu-18.04
+    steps:
+    - uses: actions/checkout@v1
+    - uses: ros-tooling/setup-ros@0.0.13
+    - uses: ros-tooling/action-ros-lint@0.0.5
+      with:
+        linter: xmllint
+        package-name: ros2_control_demo_communication_gazebo ros2_control_demo_communication_headless ros2_control_demo_hardware ros2_control_demo_robot
+
+  ament_lint_cpp:
+    name: ament_${{ matrix.linter }}
+    runs-on: ubuntu-18.04
+    strategy:
+      fail-fast: false
+      matrix:
+          linter: [cppcheck, cpplint, uncrustify]
+    steps:
+    - uses: actions/checkout@v1
+    - uses: ros-tooling/setup-ros@0.0.13
+    - uses: ros-tooling/action-ros-lint@0.0.5
+      with:
+        linter: ${{ matrix.linter }}
+        package-name: ros2_control_demo_communication_gazebo ros2_control_demo_communication_headless ros2_control_demo_hardware ros2_control_demo_robot

.gitignore

+.kdev4/
+
+
+*~
+*.kate-swp
+*.kdev4

CONTRIBUTING.md

+# Contributing Guidelines
+Thank you for your interest in contributing to `ros2_control_demos`.
+Whether it's a bug report, new feature, correction, or additional
+documentation, we greatly value feedback and contributions from our community.
+
+Please read through this document before submitting any issues or pull requests to ensure we have all the necessary
+information to effectively respond to your bug report or contribution.
+
+
+## Reporting Bugs/Feature Requests
+We welcome you to use the GitHub issue tracker to report bugs or suggest features.
+
+When filing an issue, please check [existing open][issues], or [recently closed][closed-issues], issues to make sure 
+ somebody else hasn't already reported the issue.
+Please try to include as much information as you can. Details like these are incredibly useful:
+
+* A reproducible test case or series of steps
+* The version of our code being used
+* Any modifications you've made relevant to the bug
+* Anything unusual about your environment or deployment
+
+
+## Contributing via Pull Requests
+Contributions via pull requests are much appreciated.
+Before sending us a pull request, please ensure that:
+
+1. You are working against the latest source on the *master* branch.
+2. You check existing open, and recently merged, pull requests to make sure someone else hasn't addressed the problem already.
+3. You open an issue to discuss any significant work - we would hate for your time to be wasted.
+
+To send us a pull request, please:
+
+1. Fork the repository.
+2. Modify the source; please focus on the specific change you are contributing.
+  If you also reformat all the code, it will be hard for us to focus on your change.
+3. Ensure local tests pass.
+4. Commit to your fork using clear commit messages.
+5. Send a pull request, answering any default questions in the pull request interface.
+6. Pay attention to any automated CI failures reported in the pull request, and stay involved in the conversation.
+
+GitHub provides additional documentation on [forking a repository](https://help.github.com/articles/fork-a-repo/) and
+[creating a pull request](https://help.github.com/articles/creating-a-pull-request/).
+
+
+## Finding contributions to work on
+Looking at the existing issues is a great way to find something to contribute on.
+As this project, by default, uses the default GitHub issue labels
+  (enhancement/bug/duplicate/help wanted/invalid/question/wontfix), looking at any ['help wanted'][help-wanted] issues 
+  is a great place to start.
+
+
+## Licensing
+Any contribution that you make to this repository will be under the Apache 2 License, as dictated by that [license]:
+
+~~~
+5. Submission of Contributions. Unless You explicitly state otherwise,
+   any Contribution intentionally submitted for inclusion in the Work
+   by You to the Licensor shall be under the terms and conditions of
+   this License, without any additional terms or conditions.
+   Notwithstanding the above, nothing herein shall supersede or modify
+   the terms of any separate license agreement you may have executed
+   with Licensor regarding such Contributions.
+~~~
+
+[issues]: https://github.com/ros-controls/ros2_control_demos/issues
+[closed-issues]: https://github.com/ros-controls/ros2_control_demos/issues?utf8=%E2%9C%93&q=is%3Aissue%20is%3Aclosed%20
+[help-wanted]: https://github.com/ros-controls/ros2_control_demos/issues?q=is%3Aopen+is%3Aissue+label%3A%22help+wanted%22
+[license]: http://www.apache.org/licenses/LICENSE-2.0.html

LICENSE

+
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README.md

-# ros2_control_demos
\ No newline at end of file
+# ROS2 Control Demos
+
+[![Build Status](https://github.com/ros-controls/ros2_control_demos/workflows/CI/badge.svg?branch=master)](https://github.com/ros-controls/ros2_control_demos/actions?query=workflow%3ACI)
+[![Linters Status](https://github.com/ros-controls/ros2_control_demos/workflows/Linters/badge.svg?branch=master)](https://github.com/ros-controls/ros2_control_demos/actions?query=workflow%3ALinters)
+[![Coverage Status](https://github.com/ros-controls/ros2_control_demos/workflows/Coverage/badge.svg?branch=master)](https://github.com/ros-controls/ros2_control_demos/actions?query=workflow%3ACoverage)
+[![Licence](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://opensource.org/licenses/Apache-2.0)
+
+This repository provides templates for the development of `ros2_control`-enabled robots and a simple simulation of a robot to demonstrate and prove `ros2_control` concepts.
+
+## Goals
+
+The repository has two goals:
+
+1. It provides templates for faster start of implementing own hardware and controllers;
+2. The repository is a validation environment for `ros2_control` concepts, which can only be tested during run-time (e.g., execution of controllers by the controller manager,  communication between robot hardware and controllers).
+
+
+## Description
+
+The repository is inspired by [ros_control_boilerplate](https://github.com/PickNikRobotics/ros_control_boilerplate) repository from Dave Coleman.
+The simulation has three parts/packages:
+1. The first package, `ros2_control_demo_communication_headless`, uses scripts to simulate communication to and movements of virtual hardware.
+This package does not have any dependencies except on the `ros2` core packages and can, therefore, be used on SoC-hardware of headless systems.
+2. The second package, `ros2_control_demo_communication_gazebo`, uses a gazebo simulator to simulate the *RRBot* and its physics.
+This package is useful to test the connection of `ros2_control` to the gazebo simulator and to detect any missing plugins.
+3. The third package holds template/example files for `ros2_control` enabled robots and controllers.
+The intention of those files is to simplify start with `ros2_control` and to enable faster integration of new robots and controllers.
+
+This repository demonstrates the following `ros2_control` concepts:
+
+* Creating of `hardware_interface` for a Robot, Sensor, and Actor
+* Creating a robot description in the form of YAML files
+* Loading configuration and starting robot using launch files 
+* Control of two joints of *RRBot*
+* Using simulated robots and starting `ros_control` with gazebo simulator
+* Implementing of controller switching strategy for a robot
+* Using joint limits and transmission concepts in `ros2_control`
+* TBD
+
+# Getting Started with ROS2 Control
+
+ To test `demo_robot` start launch file with:
+```
+ros2 launch ros2_control_demo_robot demo_robot_launch.py
+```
+for headless version of the `demo_robot` or
+```
+ros2 launch ros2_control_demo_robot demo_robot_modular_launch.py
+```
+for headless modular version of the `demo_robot` which uses separate interfaces for its sensors and actuators.
+
+## Class Diagram of `demo_robot`
+
+The figure hereunder depicts the class diagram of `ros2_control_demos` metapackage, i.e., `demo_robot`, together with used interfaces and classes from `ros2_control` package.
+Diagram gives an overview of the components needed for a robot that is ROS2-Control compatible.
+In the middle of the diagram (no color), entities are core components of `ros2_control`.
+Green colored entities are "ROS2-Control"-standardized data structures, hardware representations, and communication interfaces.
+Blue colored is the implementation of `demo_robot`.
+A large amount of classes is for the exemplary purpose, therefore __don't worry__ you probably don't need so many different interfaces and classes.
+
+![ROS2 Control Demo Robot - Class Diagram][ros2_control_demo_robot_class_diagram]
+
+
+# Making a Robot for ROS2-Control Compatible
+
+Before starting the implementation of your robot, please check the following diagram:
+
+![ROS2 Control - Enabling a new Robot][ros2_control_new_robot]
+
+
+
+<!-- References -->
+[ros2_control_demo_robot_class_diagram]: docs/ros2_control_demo_robot_class_diagram.svg "ROS2 Control Demo Robot - Class Diagram"
+[ros2_control_new_robot]: docs/ros2_control_new_robot.svg "ROS2 Control - Enabling a new Robot"

codecov.yml

+fixes:
+  - "ros_ws/src/ros2_control_demos/::"

ros2_control_demo_communication_gazebo/CMakeLists.txt

+cmake_minimum_required(VERSION 3.5)
+project(ros2_control_demo_communication_gazebo)
+
+# Default to C99
+if(NOT CMAKE_C_STANDARD)
+  set(CMAKE_C_STANDARD 99)
+endif()
+
+# Default to C++14
+if(NOT CMAKE_CXX_STANDARD)
+  set(CMAKE_CXX_STANDARD 14)
+endif()
+
+if(CMAKE_COMPILER_IS_GNUCXX OR CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+  add_compile_options(-Wall -Wextra -Wpedantic)
+endif()
+
+# find dependencies
+find_package(ament_cmake REQUIRED)
+
+install(DIRECTORY include/
+  DESTINATION include)
+
+if(BUILD_TESTING)
+  find_package(ament_lint_auto REQUIRED)
+  ament_lint_auto_find_test_dependencies()
+
+  ament_add_gtest(test_dummy test/test_dummy.cpp)
+  target_include_directories(test_dummy PRIVATE include)
+#   ament_target_dependencies(test_dummy rcpputils)
+endif()
+
+ament_export_libraries(${PROJECT_NAME})
+ament_export_include_directories(include)
+ament_package()

ros2_control_demo_communication_gazebo/include/ros2_control_demo_communication_gazebo/visibility_control.h

+// Copyright 2017 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.
+
+/* This header must be included by all rclcpp headers which declare symbols
+ * which are defined in the rclcpp library. When not building the rclcpp
+ * library, i.e. when using the headers in other package's code, the contents
+ * of this header change the visibility of certain symbols which the rclcpp
+ * library cannot have, but the consuming code must have inorder to link.
+ */
+
+#ifndef ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO__VISIBILITY_CONTROL_H_
+#define ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO__VISIBILITY_CONTROL_H_
+
+// This logic was borrowed (then namespaced) from the examples on the gcc wiki:
+//     https://gcc.gnu.org/wiki/Visibility
+
+#if defined _WIN32 || defined __CYGWIN__
+#ifdef __GNUC__
+#define ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO_EXPORT __attribute__((dllexport))
+#define ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO_IMPORT __attribute__((dllimport))
+#else
+#define ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO_EXPORT __declspec(dllexport)
+#define ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO_IMPORT __declspec(dllimport)
+#endif
+#ifdef ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO_BUILDING_DLL
+#define ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO_PUBLIC \
+  ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO_EXPORT
+#else
+#define ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO_PUBLIC \
+  ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO_IMPORT
+#endif
+#define ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO_PUBLIC_TYPE \
+  ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO_PUBLIC
+#define ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO_LOCAL
+#else
+#define ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO_EXPORT \
+  __attribute__((visibility("default")))
+#define ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO_IMPORT
+#if __GNUC__ >= 4
+#define ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO_PUBLIC \
+  __attribute__((visibility("default")))
+#define ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO_LOCAL \
+  __attribute__((visibility("hidden")))
+#else
+#define ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO_PUBLIC
+#define ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO_LOCAL
+#endif
+#define ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO_PUBLIC_TYPE
+#endif
+
+#endif  // ROS2_CONTROL_DEMO_COMMUNICATION_GAZEBO__VISIBILITY_CONTROL_H_

ros2_control_demo_communication_gazebo/package.xml

+<?xml version="1.0"?>
+<?xml-model href="http://download.ros.org/schema/package_format3.xsd" schematypens="http://www.w3.org/2001/XMLSchema"?>
+<package format="3">
+  <name>ros2_control_demo_communication_gazebo</name>
+  <version>0.0.0</version>
+  <description>Demo package of `ros2_control` Gazebo communication interface. This interface is used with `demo_robot` from package `ros2_control_demo_robot`.</description>
+
+  <maintainer email="ostasse@laas.fr">Olivier Stasse</maintainer>
+  <maintainer email="denis@stogl.de">Denis Štogl</maintainer>
+
+  <license>Apache License 2.0</license>
+
+  <buildtool_depend>ament_cmake</buildtool_depend>
+
+  <test_depend>ament_cmake_gtest</test_depend>
+  <test_depend>ament_lint_auto</test_depend>
+  <test_depend>ament_lint_common</test_depend>
+
+  <export>
+    <build_type>ament_cmake</build_type>
+  </export>
+</package>

ros2_control_demo_communication_gazebo/test/test_dummy.cpp

+// Copyright 2017 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.
+
+#include <gtest/gtest.h>
+
+class TestDummy : public ::testing::Test
+{
+protected:
+  static void SetUpTestCase()
+  {
+  }
+};

ros2_control_demo_communication_headless/CMakeLists.txt

+cmake_minimum_required(VERSION 3.5)
+project(ros2_control_demo_communication_headless)
+
+# Default to C99
+if(NOT CMAKE_C_STANDARD)
+  set(CMAKE_C_STANDARD 99)
+endif()
+
+# Default to C++14