# ROS 2
## First steps
1. Install [Ubuntu 24.04](https://releases.ubuntu.com/jammy/), upgrade all packages and reboot.
2. Install **ROS 2 Jazzy** following the [official instructions](https://docs.ros.org/en/jazzy/Installation/Ubuntu-Install-Debs.html). Please use `ros-jazzy-desktop` and install the dev tools.
3. Install RoboKudo apt dependencies and tooling:
   ```bash
   sudo apt install ros-jazzy-py-trees ros-jazzy-py-trees-ros ros-jazzy-py-trees-ros-viewer
   ```
4. Creating a ROS 2 workspace:

   1. Source the ROS 2 installation:
      ```bash
      source /opt/ros/jazzy/setup.bash
      ```
      Do this once per shell instance or automate this by adding the above line at the end of your `~/.bashrc`.

   2. Create a ROS 2 workspace for RK development
      ```bash
      mkdir -p ~/robokudo_ws/src
      cd ~/robokudo_ws
      colcon build --symlink-install
      source ~/robokudo_ws/install/setup.bash
      ```
      The workspace has to be sourced after re-building it. 
      However, by using the `--symlink-install` option all python scripts are symlinked instead of copied.
      This means that changes to python scripts will not require a rebuild of the workspace and thus also does not require sourcing it again.
      When changing C++ code, you will still have to rebuild and source the workspace.
5. Clone the RoboKudo repository into the workspace:
   ```bash
   cd ~/robokudo_ws/src
   # as a user:
   git clone --recurse-submodules -b ros2_jazzy https://gitlab.informatik.uni-bremen.de/robokudo/robokudo.git
   # or as a contributing developer with privileged access to the repo:
   git clone --recurse-submodules -b ros2_jazzy git@gitlab.informatik.uni-bremen.de:robokudo/robokudo.git
   ```
6. Install python dependencies using pip:
   ```bash
   sudo apt install virtualenvwrapper python3-pip

   echo "export WORKON_HOME=~/venvs" >> ~/.bashrc
   echo "source /usr/share/virtualenvwrapper/virtualenvwrapper.sh" >> ~/.bashrc
   source ~/.bashrc
   mkdir -p $WORKON_HOME
   
   mkvirtualenv robokudo --system-site-packages

   workon robokudo

   pip install -r ~/robokudo_ws/src/robokudo/requirements.txt
   ```
   Execute `workon robokudo` in every new shell to activate the virtual environment before running robokudo commands.
7. Build the Workspace again to get RK components compiled and source workspace:
   ```bash
   cd ~/robokudo_ws
   python3 -m colcon build --symlink-install
   ```
   Using `python3 -m colcon` is necessary so that the correct python interpreter is used for ROS commands.

If you want to setup a development environment with our recommended settings, continue with the following section. You can also do this step later.

**Note:** ROS2 comes with new commands and `roscore` no longer exists. To follow the tutorials replace `rosrun` with `ros2 run`, `roslaunch` with `ros2 launch` and `rosbag` with `ros2 bag`.

## IDE Setup
- Download [Pycharm for Linux from Jetbrains](https://www.jetbrains.com/pycharm/download/#section=linux) into your home directory.
- Extract the archive to `~/pycharm-<version>`:
  ```bash
  tar -xzf ~/pycharm-<version>.tar.gz -C ~/
  ```
- Create a symlink to `~/pycharm.sh` for convenience:
  ```bash
  ln -s ~/pycharm-<version>/bin/pycharm.sh ~/pycharm.sh
  ```
- Start Pycharm:
  ```bash
  source /opt/ros/iron/setup.bash # if you don't source it automatically in your .bashrc
  source ~/robokudo_ws/install/setup.bash
  ~/pycharm.sh
  ```
- Open the workspace as by clicking `Open` on the welcome screen and selecting `~/robokudo_ws`.
- In the folder view, right-click on `build` and select *Mark Directory as* → *Excluded*. Repeat this for `install` and `log`.
- Make pycharm use the venv if created in step 6 of [First steps](#first-steps):
  - Go to *File* → *Settings* → *Project* → *Python Interpreter*.
  - Click on *Add Interpreter* and select *Add local interpreter*.
  - Select *Select Existing*, click on the small folder icon next to the current python path and select `~/venvs/robokudo/bin/python3`.
  - **Make sure to select the virtualenv interpreter as the default for the project.**
- Restart PyCharm before continuing.

## Get data for development
Currently, we are working with the standard RoboSherlock tutorial bag file.
Please download the ROS bag file from [here]() to you `~/Downloads/` folder and unpack the archive:
```bash
cd ~/Downloads
wget "<link>"
tar -xzf test.tar.gz -C ~/Downloads/test
```

## Start development
- Start PyCharm as explained above:
  ```bash
  source ~/robokudo_ws/install/setup.bash
  ~/pycharm.sh
  ```
- Open a new terminal and execute:
  ```bash
  ros2 bag play ~/Downloads/test --loop
  ```
- Open a new terminal and execute:
  ```bash
  ros2 run robokudo main _ae=demo
  ```

## PyCharm Plugins
Just a list of PyCharm plugins that might be useful for development:
- Grep Console
- IdeaVim (for all the vim lovers)
- Line Profiler