feat(watchtower): add watchtower stack

compose/watchtower/.env.example

@@ -0,0 +1,5 @@
+WATCHTOWER_CLEANUP="true"
+WATCHTOWER_SCHEDULE="0 0 4 * * ?"
+WATCHTOWER_NOTIFICATION_URL=""
+# Update only containers without a com.centurylinklabs.watchtower.scope label
+WATCHTOWER_SCOPE="none"

compose/watchtower/docker-compose.yml

@@ -0,0 +1,15 @@
+services:
+  watchtower:
+    image: containrrr/watchtower
+    container_name: watchtower
+    env_file:
+      - .env
+    volumes:
+      - /var/run/docker.sock:/var/run/docker.sock
+    environment:
+      TZ: "${TZ:-Europe/Rome}"
+      WATCHTOWER_CLEANUP: "${WATCHTOWER_CLEANUP:-false}"
+      WATCHTOWER_SCHEDULE: "${WATCHTOWER_SCHEDULE:?Schedule not set}"
+      WATCHTOWER_SCOPE: "${WATCHTOWER_SCOPE:-}"
+      WATCHTOWER_NOTIFICATION_URL: "${WATCHTOWER_NOTIFICATION_URL:-}"
+    restart: always