rippy/udev/udev_daemon.py

#!/usr/bin/env python3
"""
udev-Daemon für Rippy
Erkennt Disc-Einwurf/-auswurf und erstellt Celery-Jobs.
"""

import os
import sys
import subprocess
import redis
import json

REDIS_URL = os.getenv("REDIS_URL", "redis://localhost:6379/0")
DISC_DEVICE_PATH = "/dev/disc"

# Redis verbinden
def get_redis_client():
    try:
        return redis.from_url(REDIS_URL)
    except Exception as e:
        print(f"Fehler beim Verbinden mit Redis: {e}")
        sys.exit(1)


def get_device_info(device_name: str) -> dict:
    """Ermittle Device-Info via udevadm."""
    try:
        result = subprocess.run(
            ["udevadm", "info", "-q", "property", "-n", f"/dev/{device_name}"],
            capture_output=True,
            text=True,
            timeout=5
        )
        
        info = {}
        for line in result.stdout.strip().split('\n'):
            if '=' in line:
                key, value = line.split('=', 1)
                info[key] = value
        
        return info
    except Exception as e:
        print(f"Fehler beim Auslesen von Device {device_name}: {e}")
        return {}


def create_device_symlink(device_name: str, info: dict) -> str:
    """Erstelle Symlink mit UUID/Serial-Nummer."""
    serial = info.get("ID_SERIAL", "unknown")
    model = info.get("ID_MODEL", "unknown")
    
    symlink_name = f"{model}_{serial}".replace(" ", "_")
    symlink_path = f"{DISC_DEVICE_PATH}/{symlink_name}"
    
    os.makedirs(DISC_DEVICE_PATH, exist_ok=True)
    
    # Alten Symlink entfernen falls vorhanden
    if os.path.exists(symlink_path):
        os.unlink(symlink_path)
    
    # Neuen Symlink erstellen
    os.symlink(f"/dev/{device_name}", symlink_path)
    
    return symlink_path


def delete_device_symlink(device_name: str):
    """Lösche Symlink beim Auswurf."""
    symlink_path = f"{DISC_DEVICE_PATH}/{device_name}"
    if os.path.exists(symlink_path):
        os.unlink(symlink_path)


def detect_disc_type(device_path: str) -> str:
    """Erkenne Disc-Typ (CD/DVD/Blu-ray)."""
    try:
        result = subprocess.run(
            ["isoinfo", "-d", "-i", device_path],
            capture_output=True,
            text=True,
            timeout=10
        )
        
        output = result.stdout.lower()
        
        if "rock ridge" in output or "joliet" in output:
            if "blu-ray" in output:
                return "bluray"
            return "dvd"
        elif "cda" in output:
            return "cd"
        
        return "unknown"
    except Exception:
        return "unknown"


def create_job(device_path: str, disc_type: str):
    """Erstelle Celery-Job für Disc-Erkennung."""
    try:
        client = get_redis_client()
        
        job_data = {
            "device_path": device_path,
            "disc_type": disc_type,
            "timestamp": str(int(subprocess.check_output(["date", "+%s"]).decode().strip())),
            "status": "pending"
        }
        
        client.lpush("rippy:jobs", json.dumps(job_data))
        print(f"Job erstellt: {disc_type} -> {device_path}")
        
    except Exception as e:
        print(f"Fehler beim Erstellen des Jobs: {e}")


def handle_add(device_name: str):
    """Handle Disc-Einwurf."""
    print(f"Disc-Einwurf erkannt: {device_name}")
    
    info = get_device_info(device_name)
    if not info:
        print("Konnte Device-Info nicht auslesen")
        return
    
    symlink_path = create_device_symlink(device_name, info)
    print(f"Symlink erstellt: {symlink_path}")
    
    disc_type = detect_disc_type(symlink_path)
    print(f"Disc-Typ erkannt: {disc_type}")
    
    create_job(symlink_path, disc_type)


def handle_remove(device_name: str):
    """Handle Disc-Auswurf."""
    print(f"Disc-Auswurf erkannt: {device_name}")
    delete_device_symlink(device_name)
    print(f"Symlink gelöscht: /dev/disc/{device_name}")


def main():
    """Hauptfunktion."""
    if len(sys.argv) < 3:
        print("Usage: udev_daemon.py <action> <device>")
        sys.exit(1)
    
    action = sys.argv[1]
    device = sys.argv[2]
    
    if action == "add":
        handle_add(device)
    elif action == "remove":
        handle_remove(device)
    else:
        print(f"Unbekannte Aktion: {action}")


if __name__ == "__main__":
    main()