petal-app-manager 0.1.51

A FastAPI interface for loading, managing and running Droneleaf Petal applications

Petal App Manager

A modular application framework for building and deploying "Petals" - pluggable components that can interact with various systems through a unified proxy architecture. Built on FastAPI, Petal App Manager provides a structured way to develop applications that need to interact with external systems like MAVLink devices, Redis, local databases, and more.

Overview

Petal App Manager serves as a backbone for developing modular applications. It:

• Provides a proxy system to interact with different backends (MAVLink, Redis, DynamoDB)
• Offers a plugin architecture for developing and loading "Petals"
• Handles HTTP, WebSocket, and MQTT (planned) endpoints automatically
• Manages the lifecycle of connections and resources

Dependencies

System Requirements

• Python 3.11: The application requires Python 3.11 specifically
• Redis 7.2+: For caching, message passing, and inter-process communication
• Build tools: Required for compiling Python packages from source
• PDM: Python Development Master for dependency management

Detailed Installation Steps

1. Python 3.11 Installation (via pyenv)

Python 3.11 is installed using pyenv to avoid conflicts with the system Python:

# Install build dependencies
sudo apt-get update
sudo apt-get install -y make build-essential libssl-dev zlib1g-dev \
    libbz2-dev libreadline-dev libsqlite3-dev wget curl llvm \
    libncurses5-dev libncursesw5-dev xz-utils tk-dev libffi-dev \
    liblzma-dev libgdbm-dev libnss3-dev software-properties-common ca-certificates

# Install pyenv
curl -sSL https://pyenv.run | bash

# Add pyenv to PATH (add to ~/.bashrc for persistence)
export PYENV_ROOT="$HOME/.pyenv"
export PATH="$PYENV_ROOT/bin:$PATH"

# Install Python 3.11
pyenv install 3.11.0

# Create symlinks for system-wide access
sudo ln -sf "$HOME/.pyenv/versions/3.11.0/bin/python3.11" /usr/local/bin/python3.11
sudo ln -sf "$HOME/.pyenv/versions/3.11.0/bin/pip3.11" /usr/local/bin/pip3.11

# Verify installation
python3.11 --version

[!NOTE] This installation method keeps the system's default Python 3 unchanged while making Python 3.11 available via the python3.11 command.

2. PDM Installation

PDM is used for dependency management and virtual environment handling:

# Install PDM using Python 3.11
curl -sSL https://pdm-project.org/install-pdm.py | python3.11 -

# Add PDM to PATH
export PATH="$HOME/.local/bin:$PATH"
echo 'export PATH="$HOME/.local/bin:$PATH"' >> "$HOME/.bashrc"

# Configure PDM to allow pip within virtual environments
pdm config venv.with_pip True

# Verify installation
pdm --version

3. Redis Installation and Configuration

Install Redis 7.2+ with UNIX socket support:

# Install dependencies
sudo apt-get update
sudo apt-get install -y lsb-release curl gpg apt-transport-https ca-certificates gnupg

# Add Redis official repository
curl -fsSL https://packages.redis.io/gpg | sudo gpg --dearmor -o /usr/share/keyrings/redis-archive-keyring.gpg
sudo chmod 644 /usr/share/keyrings/redis-archive-keyring.gpg

DISTRO="$(lsb_release -cs)"
echo "deb [signed-by=/usr/share/keyrings/redis-archive-keyring.gpg] https://packages.redis.io/deb $DISTRO main" | \
    sudo tee /etc/apt/sources.list.d/redis.list

# Install Redis
sudo apt-get update
sudo apt-get install -y redis

# Configure Redis for UNIX socket
sudo cp /etc/redis/redis.conf /etc/redis/redis.conf.bak

# Enable UNIX socket in configuration
sudo sed -i 's|^# *unixsocket .*|unixsocket /var/run/redis/redis-server.sock|' /etc/redis/redis.conf
sudo sed -i 's|^# *unixsocketperm .*|unixsocketperm 777|' /etc/redis/redis.conf
sudo sed -i 's|^.*daemonize.*|daemonize no|' /etc/redis/redis.conf
sudo sed -i 's|^.*supervised.*|supervised systemd|' /etc/redis/redis.conf

# Restart Redis to apply changes
sudo systemctl daemon-reload
sudo systemctl restart redis-server
sudo systemctl enable redis-server

# Set socket permissions
sudo chmod 777 /var/run/redis/redis-server.sock

# Verify installation
redis-server --version

4. Redis Development Tools (Optional, for C++ integration)

# Install hiredis library
sudo apt-get install -y libhiredis-dev

# Install redis-plus-plus (C++ client)
mkdir -p ~/.hear-cli/redis_tmp
cd ~/.hear-cli/redis_tmp
git clone https://github.com/sewenew/redis-plus-plus.git
cd redis-plus-plus
mkdir build && cd build
cmake ..
make
sudo make install

5. Controller Dashboard Setup (Optional)

The controller dashboard can be installed using:

hear-cli local_machine run_program --p controller_dashboard_prepare

Additional Dependencies

• Additional dependencies based on specific petals (e.g., MAVLink, DynamoDB clients)
• Git credentials for private repositories (if installing from source)

Installation

Production Installation (Automated via HEAR CLI)

For production deployments on target hardware (Raspberry Pi, Ubuntu systems, NVIDIA Orin), use the HEAR-CLI automated installation:

# This command installs all dependencies (Python 3.11, PDM, Redis 7.2+)
# and clones petal-app-manager to ~/.droneleaf/petal-app-manager
hear-cli local_machine run_program --p petal_app_manager_prepare_arm

This automated script performs the following:

1. Installs Python 3.11 via pyenv
2. Installs and configures PDM
3. Installs and configures Redis 7.2+ with UNIX socket support
4. Installs Redis development tools (hiredis, redis-plus-plus)
5. Clones petal-app-manager to ~/.droneleaf/petal-app-manager
6. Configures PDM to use Python 3.11: pdm use -f /usr/bin/python3.11
7. Installs production dependencies: pdm install -G prod
8. Creates the .env configuration file
9. Sets up auto-start for the service

[!NOTE] The installation script requires GitHub credentials for accessing private repositories. These will be requested during the installation process.

Environment Configuration

Create a .env file in the project root directory:

[!NOTE] All environment variables use the PETAL_ prefix to avoid conflicts with other applications.

cat > .env << 'EOF'
# .env file for Petal App Manager configuration
# General configuration
PETAL_LOG_LEVEL=INFO
PETAL_LOG_TO_FILE=true
PETAL_LOG_DIR=logs
# MAVLink configuration
PETAL_MAVLINK_ENDPOINT=udp:127.0.0.1:14551
PETAL_MAVLINK_BAUD=115200
PETAL_MAVLINK_MAXLEN=200
PETAL_MAVLINK_WORKER_SLEEP_MS=1
PETAL_MAVLINK_WORKER_THREADS=4
PETAL_MAVLINK_HEARTBEAT_SEND_FREQUENCY=5.0
PETAL_ROOT_SD_PATH=fs/microsd/log
# Cloud configuration
PETAL_ACCESS_TOKEN_URL=http://localhost:3001/session-manager/access-token
PETAL_SESSION_TOKEN_URL=http://localhost:3001/session-manager/session-token
PETAL_S3_BUCKET_NAME=devhube21f2631b51e4fa69c771b1e8107b21cb431a-dev
PETAL_CLOUD_ENDPOINT=https://api.droneleaf.io
# Local database configuration
PETAL_LOCAL_DB_HOST=localhost
PETAL_LOCAL_DB_PORT=3000
# Redis configuration
PETAL_REDIS_HOST=localhost
PETAL_REDIS_PORT=6379
PETAL_REDIS_DB=0
PETAL_REDIS_UNIX_SOCKET_PATH=/var/run/redis/redis-server.sock
PETAL_REDIS_HEALTH_MESSAGE_RATE=3.0
# Data operations URLs
PETAL_GET_DATA_URL=/drone/onBoard/config/getData
PETAL_SCAN_DATA_URL=/drone/onBoard/config/scanData
PETAL_UPDATE_DATA_URL=/drone/onBoard/config/updateData
PETAL_SET_DATA_URL=/drone/onBoard/config/setData
# MQTT client
PETAL_TS_CLIENT_HOST=localhost
PETAL_TS_CLIENT_PORT=3004
PETAL_CALLBACK_HOST=localhost
PETAL_CALLBACK_PORT=3005
PETAL_POLL_INTERVAL=1.0
PETAL_ENABLE_CALLBACKS=true
PETAL_COMMAND_EDGE_TOPIC=command/edge
PETAL_RESPONSE_TOPIC=response
PETAL_TEST_TOPIC=command
PETAL_COMMAND_WEB_TOPIC=command/web
PETAL_MQTT_HEALTH_CHECK_INTERVAL=10.0
# Proxy connection retry configuration
PETAL_MQTT_RETRY_INTERVAL=10.0
PETAL_CLOUD_RETRY_INTERVAL=10.0
PETAL_MQTT_STARTUP_TIMEOUT=5.0
PETAL_CLOUD_STARTUP_TIMEOUT=5.0
PETAL_MQTT_SUBSCRIBE_TIMEOUT=5.0
# Petal User Journey Coordinator configuration
PETAL_DEBUG_SQUARE_TEST=false
EOF

Installation From PyPI (for simple setups)

# Note: PyPI installation may not include all production dependencies
# For production use, follow the automated installation steps above
pip install petal-app-manager

You may run the server using:

uvicorn petal_app_manager.main:app --port 9000

[!WARNING] PyPI installation is simplified and may not include all dependencies required for production deployments. For production systems, use the automated installation process described above with PDM.

Development Installation (recommended for developers)

For development of petal-app-manager concurrently with petals, use the HEAR-CLI automated development setup:

# This command sets up the complete development environment
# including all petals, LeafSDK, and mavlink with pymavlink
hear-cli local_machine run_program --p petal_app_manager_prepare_sitl

This creates the following directory structure in ~/petal-app-manager-dev/:

petal-app-manager-dev/
├── LeafSDK/                              # Drone control SDK
├── mavlink/                              # MAVLink protocol (with pymavlink)
├── petal-app-manager/                    # Main application framework
├── petal-flight-log/                     # Flight log management petal
├── petal-leafsdk/                        # LeafSDK integration petal
├── petal-qgc-mission-server/            # QGroundControl mission server petal
├── petal-user-journey-coordinator/       # User journey coordination petal
└── petal-warehouse/                      # Data warehousing petal

Manual Development Setup

If you prefer to set up the development environment manually:

[!IMPORTANT] Ensure all dependencies are installed first:

• Python 3.11 (via pyenv)
• PDM with pip support enabled
• Redis 7.2+ with UNIX socket configured See the Dependencies section above for detailed installation steps.

1. Clone all required repositories:

[!NOTE] Please see the petal development guide first

```bash
mkdir -p ~/petal-app-manager-dev
cd ~/petal-app-manager-dev

# Clone core repositories
git clone https://github.com/DroneLeaf/petal-app-manager.git
git clone --recurse-submodules https://github.com/DroneLeaf/mavlink.git
git clone https://github.com/DroneLeaf/LeafSDK.git

# Clone petals
git clone https://github.com/DroneLeaf/petal-flight-log.git
git clone https://github.com/DroneLeaf/petal-leafsdk.git
git clone https://github.com/DroneLeaf/petal-qgc-mission-server.git
git clone https://github.com/DroneLeaf/petal-user-journey-coordinator.git
git clone https://github.com/DroneLeaf/petal-warehouse.git

cd petal-app-manager
```

2. Review dev dependencies in pyproject.toml

   The development dependencies are already configured with editable installations:

   [dependency-groups]
   dev = [
       "pytest>=8.4.0",
       "pytest-asyncio>=1.0.0",
       "anyio>=4.9.0",
       "pytest-cov>=6.2.1",
       "leaf-pymavlink @ file:///${PROJECT_ROOT}/../mavlink/pymavlink",
       "-e file:///${PROJECT_ROOT}/../petal-flight-log/#egg=petal-flight-log",
       "-e file:///${PROJECT_ROOT}/../petal-user-journey-coordinator/#egg=petal-user-journey-coordinator",
       "-e file:///${PROJECT_ROOT}/../petal-leafsdk/#egg=petal-leafsdk",
       "-e file:///${PROJECT_ROOT}/../petal-warehouse/#egg=petal-warehouse",
       "-e file:///${PROJECT_ROOT}/../LeafSDK/#egg=LeafSDK",
   ]
   

[!NOTE] If you would like to develop mavlink or add user-defined mavlink messages, you can do so under your local clone of mavlink https://github.com/DroneLeaf/mavlink.git. The pymavlink package will be available at ../mavlink/pymavlink and is already configured as a dependency.

[!TIP] To add your own custom petal for development:

dev = [
    # existing dependencies...
    "-e file:///${PROJECT_ROOT}/../my-custom-petal/#egg=my-custom-petal",
]

3. Configure PDM to use Python 3.11 and install dependencies

   # Ensure PDM is configured to use Python 3.11
   pdm use -f /usr/bin/python3.11
   
   # Install dependencies in editable mode
   pdm install -G dev
   

4. Create the .env configuration file (see Environment Configuration section above)

5. Run the petal-app-manager server

   # Activate the PDM virtual environment
   source .venv/bin/activate
   
   # Run the server with auto-reload for development
   uvicorn petal_app_manager.main:app --reload --port 9000
   

6. Test your endpoints:

   • Access your petal at: http://localhost:9000/petals/my-petal/hello
   • Check the API documentation: http://localhost:9000/docs

[!TIP] For debugging, you can use VSCode's launch configuration:

1. Add this to .vscode/launch.json:

   {
       "version": "0.2.0",
       "configurations": [
           {
               "name": "Petal App Manager",
               "type": "python",
               "request": "launch",
               "module": "uvicorn",
               "args": [
                   "petal_app_manager.main:app",
                   "--reload",
                   "--port", "9000"
               ],
               "jinja": true,
               "justMyCode": false
           }
       ]
   }
   

2. Start debugging with F5 or the Run and Debug panel

Project Structure

src/petal_app_manager/
├── api/                           # Core API endpoints
│   ├── admin_ui.py                # Admin dashboard UI
│   ├── bucket_api.py              # S3 bucket operations
│   ├── cloud_api.py               # Cloud service integration
│   ├── config_api.py              # Configuration management
│   ├── health.py                  # Health check endpoints
│   ├── mavftp_api.py              # MAVLink FTP operations
│   ├── mqtt_api.py                # MQTT integration
│   └── proxy_info.py              # Proxy information endpoints
├── assets/                        # Static assets
│   ├── css/
│   │   └── admin-dashboard.css
│   └── js/
│       └── admin-dashboard.js
├── config.py                      # Configuration management
├── examples/                      # Usage examples
│   ├── example_mqtt_usage.py
│   ├── example_redis_petal.py
│   ├── hear_fc_communication_example.py
│   ├── integration_test_hear_fc.py
│   ├── logging_example_petal.py
│   ├── mavlink_burst_filtering_example.py
│   ├── proxy_usage_example.py
│   ├── redis_usage_examples.py
│   └── simple_redis_petal.py
├── health_service.py              # Health monitoring service
├── logger.py                      # Logging configuration
├── main.py                        # FastAPI application setup
├── models/                        # Data models
│   ├── health.py
│   └── __init__.py
├── organization_manager.py        # Organization management
├── plugins/                       # Plugin architecture
│   ├── base.py                    # Base Petal class
│   ├── decorators.py              # HTTP/WebSocket decorators
│   └── loader.py                  # Dynamic petal loading
├── proxies/                       # Backend communication
│   ├── base.py                    # BaseProxy abstract class
│   ├── bucket.py                  # S3 bucket proxy
│   ├── cloud.py                   # Cloud database proxy
│   ├── external.py                # MAVLink communication
│   ├── localdb.py                 # Local DynamoDB proxy
│   ├── mqtt.py                    # MQTT proxy
│   ├── org_utils.py               # Organization utilities
│   └── redis.py                   # Redis proxy
├── templates/                     # HTML templates
│   └── admin-dashboard.html
└── utils/                         # Utility functions
    ├── log_tool.py                # Log management tool
    ├── machineid_arm              # Machine ID binary (ARM)
    └── machineid_x86              # Machine ID binary (x86)

Available Petals

The framework includes the following production petals (installed via pdm install -G prod):

• petal-flight-log (v0.1.6): Flight log management and uploading
• petal-warehouse (v0.1.7): Data warehousing and analytics
• petal-leafsdk (v0.1.12): LeafSDK integration for drone control
• petal-user-journey-coordinator (v0.1.2): User journey and mission coordination

Additional petals for development:

• petal-qgc-mission-server: QGroundControl mission server integration

Activating Petals

Petals must be activated in the proxies.yaml configuration file to be loaded at runtime. Add your petal to the enabled_petals list and specify its proxy dependencies:

enabled_petals:
  - flight_records
  - petal_warehouse
  - mission_planner
  - petal_user_journey_coordinator
  - my_custom_petal  # Add your petal here

petal_dependencies:
  my_custom_petal:
    - redis          # List required proxies
    - ext_mavlink

[!TIP] After adding a new petal to your dependencies in pyproject.toml, remember to:

1. Run pdm install -G dev (or -G prod for production petals)
2. Add the petal name to enabled_petals in proxies.yaml
3. Specify any proxy dependencies in petal_dependencies
4. Restart the application

How It Works

Proxy System

The framework uses proxies to interact with different backends:

• MavLinkExternalProxy: Communicates with PX4/MAVLink devices
• RedisProxy: Interfaces with Redis for caching and pub/sub
• LocalDBProxy: Provides access to a local DynamoDB instance

Proxies are initialized at application startup and are accessible to all petals.

Accessing the API

Once running, access:

• API documentation: http://localhost:9000/docs
• ReDoc documentation: http://localhost:9000/redoc
• Petal endpoints: http://localhost:9000/petals/{petal-name}/{endpoint}

Troubleshooting

Common Issues

• Python 3.11 Not Found:

  • Verify pyenv installation: pyenv versions
  • Check symlinks: ls -la /usr/bin/python3.11 /usr/local/bin/python3.11
  • Ensure pyenv is in PATH: export PATH="$HOME/.pyenv/bin:$PATH"
  • Try sourcing bashrc: source ~/.bashrc

• PDM Installation Fails:

  • Ensure Python 3.11 pip is available: python3.11 -m pip --version
  • Check that ~/.local/bin is in PATH
  • Verify venv module: python3.11 -m venv --help

• Redis Connection Errors:

  • Ensure Redis server is running: sudo systemctl status redis-server
  • Verify Redis version: redis-server --version (should be 7.2+)
  • Check UNIX socket exists: ls -la /var/run/redis/redis-server.sock
  • Verify socket permissions: sudo chmod 777 /var/run/redis/redis-server.sock
  • Check Redis configuration: sudo grep -E "^unixsocket|^unixsocketperm" /etc/redis/redis.conf
  • Test Redis connection: redis-cli -s /var/run/redis/redis-server.sock ping

• Redis Configuration Issues:

  • Backup exists at /etc/redis/redis.conf.bak if you need to restore
  • Ensure daemonize no and supervised systemd are set correctly
  • After config changes, restart: sudo systemctl restart redis-server

• MAVLink Connection Issues:

  • Verify the connection string in .env file
  • Check that the MAVLink endpoint is accessible