Refactor swarm/core.yml to add shepherd service for managing containers

swarm/core.yml

@@ -123,6 +123,26 @@ services:
       # Use the public network created to be shared between Traefik and
       # any other service that needs to be publicly available with HTTPS
       - traefik-public
+  shepherd:
+    image: containrrr/shepherd
+    environment:
+      # Beware YAML gotchas regarding quoting:
+      # With KEY: 'VALUE', quotes are part of yaml syntax and thus get stripped
+      # but with KEY='VALUE', they are part of the value and stay there,
+      # causing problems!
+      TZ: 'Asia/Singapore'
+      SLEEP_TIME: '60m'
+      FILTER_SERVICES: ''
+      VERBOSE: 'true'
+      UPDATE_OPTIONS: '--update-delay=30s'
+      ROLLBACK_OPTIONS: '--rollback-delay=0s'
+      IMAGE_AUTOCLEAN_LIMIT: '5'
+    volumes:
+      - /var/run/docker.sock:/var/run/docker.sock
+    deploy:
+      placement:
+        constraints:
+          - node.role == manager
 
 volumes:
   # Create a volume to store the certificates, there is a constraint to make sure