demo cache to vol

extras/example-rclone-backend/backup.env

@@ -10,6 +10,7 @@ EXCLUDE_BIND_MOUNTS=false
 RESTIC_REPOSITORY=rclone:uplink:mybucket
 RESTIC_PASSWORD="password"
 
+# this env var creates on-the-fly a remote named "uplink"
 RCLONE_CONFIG_UPLINK_TYPE=storj
 # access grant must have permission to use bucket
 RCLONE_CONFIG_UPLINK_ACCESS_GRANT=

extras/example-rclone-backend/compose.yaml

@@ -9,7 +9,7 @@ services:
       # Map in docker socket
       - /var/run/docker.sock:/var/run/docker.sock
       # Map restic cache
-      - ./restic_cache:/cache
+      - restic_cache:/cache
   postgres:
     image: postgres:12
     env_file:
@@ -21,3 +21,4 @@ services:
 
 volumes:
   pgdata:
+  restic_cache: