post-create.sh

Overview

The post-create.sh script performs one-time initialization when the development container is first created. It sets up the ROS2 environment, clones TurtleBot3 repositories, and configures user settings. Location: .devcontainer/post-create.sh Execution: Automatically run by postCreateCommand in devcontainer.json Runtime: Approximately 1-2 minutes (depends on network speed)

Script structure

Initialization

#!/bin/bash
set -e

echo "=========================================="
echo "Post-create: Setting up TurtleBot3 Jazzy"
echo "=========================================="

Sets strict error handling and displays banner.

GPU detection

echo "Detecting graphics capabilities..."
if command -v glxinfo &> /dev/null; then
    if glxinfo | grep -q "direct rendering: Yes"; then
        echo "[OK] Hardware GPU acceleration available"
        USE_SOFTWARE_RENDERING=false
    else
        echo "[WARNING] No hardware GPU acceleration detected"
        echo "[INFO] Will use software rendering for stability"
        USE_SOFTWARE_RENDERING=true
    fi
else
    echo "[WARNING] Cannot detect GPU - will use software rendering"
    USE_SOFTWARE_RENDERING=true
fi

Purpose: Detects if hardware GPU acceleration is available Behavior:

Checks if glxinfo is available
Tests for direct rendering support
Sets USE_SOFTWARE_RENDERING flag for later use
Defaults to software rendering if detection fails

ROS2 environment setup

source /opt/ros/jazzy/setup.bash

Sources the base ROS2 Jazzy installation for use during setup.

Bashrc configuration

The script appends comprehensive configuration to ~/.bashrc:

ROS2 setup

cat >> ~/.bashrc << 'BASHRC_EOF'

# ROS2 Jazzy setup
source /opt/ros/jazzy/setup.bash
if [ -f /workspace/turtlebot3_ws/install/setup.bash ]; then
    source /workspace/turtlebot3_ws/install/setup.bash
fi

# Environment variables
export ROS_DOMAIN_ID=30
export TURTLEBOT3_MODEL=burger
export RMW_IMPLEMENTATION=rmw_cyclonedds_cpp
export GZ_VERSION=harmonic
export QT_QPA_PLATFORM=xcb

BASHRC_EOF

Configuration details:

Sources ROS2 Jazzy on every shell startup
Sources workspace overlay if built
Sets ROS_DOMAIN_ID to 30 (isolates network traffic)
Configures TurtleBot3 Burger as default model
Uses CycloneDDS as DDS implementation
Sets Gazebo Harmonic as simulator version

Software rendering fallback

if [ "$USE_SOFTWARE_RENDERING" = true ]; then
    cat >> ~/.bashrc << 'BASHRC_EOF'
# Software rendering (for GPU compatibility)
export LIBGL_ALWAYS_SOFTWARE=1
echo "[INFO] Using software rendering for Gazebo (GPU not available)"
BASHRC_EOF
fi

Adds software rendering configuration if GPU not detected.

Bash aliases

cat >> ~/.bashrc << 'BASHRC_EOF'

# Useful aliases
alias cb='cd /workspace/turtlebot3_ws && colcon build --symlink-install'
alias sb='source /workspace/turtlebot3_ws/install/setup.bash'
alias tb3_empty='ros2 launch turtlebot3_gazebo empty_world.launch.py'
alias tb3_world='ros2 launch turtlebot3_gazebo turtlebot3_world.launch.py'
alias tb3_house='ros2 launch turtlebot3_gazebo turtlebot3_house.launch.py'
alias tb3_teleop='ros2 run turtlebot3_teleop teleop_keyboard'
alias tb3_slam='ros2 launch turtlebot3_cartographer cartographer.launch.py use_sim_time:=True'
alias tb3_nav='ros2 launch turtlebot3_navigation2 navigation2.launch.py use_sim_time:=True map:=$HOME/maps/my_map.yaml'

# Gazebo with software rendering fallback
alias tb3_empty_sw='LIBGL_ALWAYS_SOFTWARE=1 ros2 launch turtlebot3_gazebo empty_world.launch.py'
alias tb3_world_sw='LIBGL_ALWAYS_SOFTWARE=1 ros2 launch turtlebot3_gazebo turtlebot3_world.launch.py'
alias tb3_house_sw='LIBGL_ALWAYS_SOFTWARE=1 ros2 launch turtlebot3_gazebo turtlebot3_house.launch.py'
BASHRC_EOF

See Aliases for complete documentation.

Workspace permissions

sudo chown -R $(whoami):$(whoami) /workspace/turtlebot3_ws
mkdir -p /workspace/turtlebot3_ws/src

Ensures correct ownership and creates source directory.

Repository cloning

cd /workspace/turtlebot3_ws/src

# Check if repositories exist AND have content
NEED_CLONE=false

if [ ! -d "turtlebot3" ]; then
    NEED_CLONE=true
    echo "TurtleBot3 directory not found"
elif [ ! -f "turtlebot3/turtlebot3/package.xml" ]; then
    NEED_CLONE=true
    echo "TurtleBot3 directory exists but is empty - will re-clone"
    rm -rf DynamixelSDK turtlebot3 turtlebot3_msgs turtlebot3_simulations
fi

if [ "$NEED_CLONE" = true ]; then
    echo "Cloning TurtleBot3 repositories..."
    
    git clone -b jazzy https://github.com/ROBOTIS-GIT/DynamixelSDK.git
    git clone -b jazzy https://github.com/ROBOTIS-GIT/turtlebot3_msgs.git
    git clone -b jazzy https://github.com/ROBOTIS-GIT/turtlebot3.git
    git clone -b jazzy https://github.com/ROBOTIS-GIT/turtlebot3_simulations.git
    
    echo "[OK] Repositories cloned"
else
    echo "[OK] TurtleBot3 repositories already exist with content"
fi

Features:

Intelligent detection of existing repositories
Validates content by checking for package.xml
Idempotent: safe to run multiple times
Clones Jazzy branch from official ROBOTIS repositories

Repositories cloned:

DynamixelSDK: Motor control SDK
turtlebot3_msgs: Message definitions
turtlebot3: Core packages
turtlebot3_simulations: Gazebo simulation

Package verification

cd /workspace/turtlebot3_ws
PACKAGE_COUNT=$(find src/ -name "package.xml" 2>/dev/null | wc -l)
echo "Verified $PACKAGE_COUNT package.xml files"

Counts and reports the number of ROS2 packages found.

Dependency management

# Initialize rosdep if not already done
if [ ! -f /etc/ros/rosdep/sources.list.d/20-default.list ]; then
    echo "Initializing rosdep..."
    sudo rosdep init || true
fi

# Update rosdep
echo "Updating rosdep..."
rosdep update

# Install dependencies
echo "Installing dependencies..."
rosdep install --from-paths src --ignore-src -r -y || true

Steps:

Initialize rosdep database (if not done)
Update rosdep package lists
Install all package dependencies from src/

Flags:

--from-paths src: Scan src/ directory
--ignore-src: Don’t install packages we’re building
-r: Continue on error
-y: Answer yes to prompts

Additional setup

Maps directory

mkdir -p ~/maps

Creates directory for storing SLAM maps.

GPU info file

cat > ~/GPU_INFO.txt << 'EOF'
GPU Detection Results
=====================

EOF

if command -v glxinfo &> /dev/null; then
    echo "GPU Vendor: $(glxinfo | grep "OpenGL vendor" || echo "Unknown")" >> ~/GPU_INFO.txt
    echo "GPU Renderer: $(glxinfo | grep "OpenGL renderer" || echo "Unknown")" >> ~/GPU_INFO.txt
    echo "Direct Rendering: $(glxinfo | grep "direct rendering" || echo "Unknown")" >> ~/GPU_INFO.txt
else
    echo "glxinfo not available" >> ~/GPU_INFO.txt
fi

echo "" >> ~/GPU_INFO.txt
echo "If Gazebo crashes, try: tb3_empty_sw (software rendering)" >> ~/GPU_INFO.txt

Generates a helpful GPU information file at ~/GPU_INFO.txt with:

GPU vendor and renderer information
Direct rendering status
Troubleshooting hint for Gazebo crashes

Completion message

echo "=========================================="
echo "[OK] Post-create setup complete!"
if [ "$USE_SOFTWARE_RENDERING" = true ]; then
    echo "[INFO] Software rendering enabled (see ~/GPU_INFO.txt)"
fi
echo "=========================================="

Exit behavior

Success: Exits with code 0
Failure: Exits with non-zero code (due to set -e)

Files modified

~/.bashrc: Appended with ROS2 configuration and aliases
~/GPU_INFO.txt: Created with GPU information
~/maps/: Directory created
/workspace/turtlebot3_ws/src/: Repositories cloned

Troubleshooting

Script fails during repository cloning

Cause: Network issues or rate limiting Solution: Re-run the script manually:

bash /workspace/turtlebot3_ws/.devcontainer/post-create.sh

Dependencies fail to install

Cause: Missing or outdated rosdep entries Solution: Update rosdep and retry:

rosdep update
rosdep install --from-paths src --ignore-src -r -y

Software rendering always enabled

Cause: GPU not properly passed to container Solution: Check Docker GPU configuration and restart container

Project Structure

Scripts

Commands & Aliases

Troubleshooting

Overview

Script structure

Initialization

GPU detection

ROS2 environment setup

Bashrc configuration

ROS2 setup

Software rendering fallback

Bash aliases

Workspace permissions

Repository cloning

Package verification

Dependency management

Additional setup

Maps directory

GPU info file

Completion message

Exit behavior

Files modified

Troubleshooting

Script fails during repository cloning

Dependencies fail to install

Software rendering always enabled

Build docs developers (and LLMs) love

Project Structure

Scripts

Commands & Aliases

Troubleshooting

​Overview

​Script structure

​Initialization

​GPU detection

​ROS2 environment setup

​Bashrc configuration

​ROS2 setup

​Software rendering fallback

​Bash aliases

​Workspace permissions

​Repository cloning

​Package verification

​Dependency management

​Additional setup

​Maps directory

​GPU info file

​Completion message

​Exit behavior

​Files modified

​Troubleshooting

​Script fails during repository cloning

​Dependencies fail to install

​Software rendering always enabled

Build docs developers (and LLMs) love

Overview

Script structure

Initialization

GPU detection

ROS2 environment setup

Bashrc configuration

ROS2 setup

Software rendering fallback

Bash aliases

Workspace permissions

Repository cloning

Package verification

Dependency management

Additional setup

Maps directory

GPU info file

Completion message

Exit behavior

Files modified

Troubleshooting

Script fails during repository cloning

Dependencies fail to install

Software rendering always enabled