docker-compose.example.yml

# Example: watchdog as a sidecar that monitors all containers on the host.
#
# How it works (same approach as cAdvisor, Prometheus node-exporter):
#   - Mount the HOST's /proc into the watchdog container read-only
#   - Linux has a single process table — containers are just namespaced views
#   - Watchdog reads host /proc and sees processes from ALL containers
#   - No need to couple watchdog to a specific container via pid: "service:..."
#
# Socket sharing:
#   - The Laravel/Symfony module writes to a Unix socket
#   - Both the app container and watchdog container mount the same volume
#   - They communicate through the shared socket file

services:
  app:
    image: your-app-image
    # ... your app config
    volumes:
      - watchdog-socket:/var/run/watchdog  # shared socket directory

  horizon:
    image: your-app-image
    command: php artisan horizon
    volumes:
      - watchdog-socket:/var/run/watchdog  # shared socket directory

  watchdog:
    image: yangusik/php-watchdog:latest
    volumes:
      - /proc:/host/proc:ro                         # host /proc mounted at /host/proc to avoid overwriting container's /proc
      - ./watchdog.yml:/etc/watchdog/watchdog.yml:ro
      - watchdog-socket:/var/run/watchdog           # shared socket directory
      - watchdog-reports:/var/log/watchdog          # reports output
    restart: unless-stopped
    # Run as the same user as PHP workers so the Unix socket is writable by them.
    # Reading /proc is allowed for any user on Linux.
    # Killing processes requires matching UID — if kill: false, any user works.
    # Find your PHP worker UID: docker exec <container> id www-data
    user: "1000:1000"

volumes:
  watchdog-socket:
  watchdog-reports: