Development Container

ros2_medkit includes a ready-to-use VS Code development container (devcontainer) that provides a complete, reproducible development environment.

Overview 

The devcontainer provides:

Ubuntu 24.04 base image
ROS 2 Jazzy desktop-full installation
C++17 toolchain (GCC 13)
Development tools: CMake, colcon, rosdep, clang-format, clang-tidy
Documentation tools: Doxygen, Sphinx, PlantUML
Code coverage: lcov
VS Code extensions: C++, Python, CMake, GitHub Copilot, GitLens

Prerequisites 

VS Code with the Dev Containers extension
Docker (Docker Desktop on Windows/macOS, Docker Engine on Linux)
Git with SSH key configured (optional, for pushing to remotes)

Quick Start 

Clone the repository with submodules:

git clone --recurse-submodules https://github.com/selfpatch/ros2_medkit.git
cd ros2_medkit

If you already cloned without submodules:

git submodule update --init --recursive

Open in VS Code:
```
code .
```
Reopen in Container:

When VS Code opens, click “Reopen in Container” in the notification popup, or:
- Press F1 → “Dev Containers: Reopen in Container”
Wait for container build:

The first build takes 5-10 minutes. Subsequent opens use the cached image.
Start developing:

Once the container starts, the terminal will have ROS 2 sourced automatically.

Container Configuration 

devcontainer.json 

The .devcontainer/devcontainer.json configures:

Build Settings:

Uses custom Dockerfile for ROS 2 Jazzy setup
Passes USERNAME from host for consistent file permissions
Network mode: host for ROS 2 discovery

Workspace Mounting:

Workspace mounted at /home/<username>/workspace
SSH keys mounted read-only for git operations
Git config mounted for commit identity

VS Code Extensions:

Pre-installed extensions for C++, Python, CMake, YAML, and documentation development.

Post-Create Script:

Runs setup-env.sh to initialize rosdep and source ROS 2 environment.

Dockerfile 

The .devcontainer/Dockerfile installs:

System Packages:

ros-jazzy-desktop-full - Complete ROS 2 installation
python3-colcon-common-extensions - Build system
doxygen, graphviz, plantuml - Documentation
clang-format, clang-tidy - Code formatting/linting
lcov - Coverage reports
hadolint - Dockerfile linting

Python Packages:

sphinx, sphinx-rtd-theme, sphinx-needs - Documentation
black, flake8-* - Python linting
pytest, pytest-repeat, pytest-rerunfailures - Testing

Development Workflow 

Building the Project 

cd ~/workspace
rosdep install --from-paths src --ignore-src -r -y
colcon build --symlink-install

Running Tests 

# All tests
colcon test && colcon test-result --verbose

# Unit tests only
colcon test --ctest-args -E test_integration

# Linters only
colcon test --ctest-args -L linters

Building Documentation 

cd ~/workspace/docs
pip install -e .
sphinx-build -b html . _build/html

Generating Coverage 

colcon build --cmake-args -DCMAKE_BUILD_TYPE=Debug -DENABLE_COVERAGE=ON
colcon test
# Coverage report in build/ros2_medkit_gateway/coverage/

Customization 

Adding Extensions 

Edit the customizations.vscode.extensions array in devcontainer.json:

"extensions": [
  "ms-vscode.cpptools",
  "your.extension-id"
]

Changing Shell 

The container uses zsh with Oh My Zsh by default. To use bash, modify the features section in devcontainer.json:

"features": {
  "ghcr.io/devcontainers/features/common-utils:2": {
    "installZsh": false,
    "configureZshAsDefaultShell": false
  }
}

Persistent Storage 

Add volume mounts for data that should persist across container rebuilds:

"mounts": [
  "source=ros2-medkit-build-cache,target=/home/${localEnv:USER}/workspace/build,type=volume"
]

Troubleshooting 

Container fails to start 

SSH key issues:

If you don’t have SSH keys, remove or comment out the SSH mount:

// "source=${localEnv:HOME}/.ssh,target=/home/${localEnv:USER}/.ssh,..."

Docker socket permissions:

On Linux, ensure your user is in the docker group:

sudo usermod -aG docker $USER
# Log out and back in

ROS 2 commands not found 

The ROS 2 environment should be sourced automatically. If not:

source /opt/ros/jazzy/setup.bash

Rebuild the container if setup-env.sh didn’t run:

Press F1 → “Dev Containers: Rebuild Container”

Slow file I/O on macOS/Windows 

For better performance with large workspaces, consider using a named volume for the build directory instead of bind mounting.