A Rust-based fan control daemon with REST API for dynamic configuration management.

• Automatic fan control based on temperature curves
• REST API for real-time configuration management
• Support for multiple fans with individual configurations
• Linear interpolation between temperature steps
• Graceful shutdown handling

The daemon provides a REST API on http://127.0.0.1:8080/api/v1/ with the following endpoints:

• GET /api/v1/status - Get current status of all fans (temperature, power, configuration)
• GET /api/v1/config - Get the current configuration
• PUT /api/v1/config - Update the entire configuration

• GET /api/v1/fans - Get all fan configurations
• GET /api/v1/fans/{name} - Get configuration for a specific fan
• PUT /api/v1/fans/{name} - Update fan curve (steps) for a specific fan
• DELETE /api/v1/fans/{name} - Remove a fan from configuration
• POST /api/v1/fans - Add a new fan to configuration

• POST /api/v1/stop - Send stop signal to the daemon
• POST /api/v1/start - Start the daemon (not implemented yet)

All API responses follow this format:

{
  "success": true,
  "message": "Operation completed successfully",
  "data": { ... }
}

curl -X PUT http://127.0.0.1:8080/api/v1/fans/fan_1 \
  -H "Content-Type: application/json" \
  -d '{
    "steps": [
      {"temp": 30, "power": 20},
      {"temp": 50, "power": 50},
      {"temp": 70, "power": 80},
      {"temp": 85, "power": 100}
    ]
  }'

curl http://127.0.0.1:8080/api/v1/status

Response:

{
  "success": true,
  "message": "Status retrieved successfully",
  "data": [
    {
      "name": "fan_1",
      "temperature": 45,
      "power": 60,
      "sensor_input": "/sys/class/hwmon/hwmon0/temp1_input",
      "pwm_input": "/sys/class/hwmon/hwmon1/pwm1",
      "steps": [
        {"temp": 30, "power": 20},
        {"temp": 50, "power": 50},
        {"temp": 70, "power": 80},
        {"temp": 85, "power": 100}
      ]
    }
  ]
}

The daemon reads configuration from config.json. The configuration format is JSON and can be updated via the REST API.

cargo build --release

sudo ./target/release/coold-rs daemon
# or simply (daemon is the default)
sudo ./target/release/coold-rs

The daemon will start both the fan control service and the REST API server on port 8080.

The CLI provides an easy way to interact with the daemon:

# Get current fan status
./target/release/coold-rs cli status

# List all fans
./target/release/coold-rs cli list

# Get specific fan configuration
./target/release/coold-rs cli get fan_1

# Update fan curve
./target/release/coold-rs cli update fan_1 "30:20,50:50,70:80,85:100"

# Add new fan
./target/release/coold-rs cli add \
  --sensor-name "coretemp" \
  --sensor-input "temp1_input" \
  --pwm-name "nct6775" \
  --pwm-input "pwm1" \
  "30:20,50:50,70:80,85:100"

# Remove fan
./target/release/coold-rs cli remove fan_1

# Update entire configuration from file
./target/release/coold-rs cli update-config new_config.json

# Stop the daemon
./target/release/coold-rs cli stop

• status - Get current status of all fans
• config - Get current configuration
• update-config <file> - Update entire configuration from file
• list - List all fans
• get <name> - Get specific fan configuration
• update <name> <steps> - Update fan curve (format: "temp:power,temp:power,...")
• add - Add new fan with required parameters
• remove <name> - Remove fan
• stop - Stop the daemon
• start - Start the daemon

• src/daemon.rs - Core fan control logic and configuration management
• src/api.rs - REST API implementation using Actix-web
• src/cli.rs - Command-line interface for interacting with the REST API
• src/main.rs - Application entry point with mode selection (daemon/CLI)

The application uses a shared FanController instance that can be safely accessed from both the daemon thread and the API server, allowing for real-time configuration updates without restarting the service.

The CLI provides a user-friendly interface to the REST API, making it easy to manage fan configurations from the command line without needing to construct HTTP requests manually.