use host and port variables

docker-compose.yml

@@ -6,15 +6,16 @@ services:
       context: .
     container_name: cannery
     environment:
+      HOST: "your.domain.com"
       DATABASE_URL: "ecto://postgres:postgres@cannery-db/cannery"
       # generate a random base64 string 64 characters long, preferably not from a website
       SECRET_KEY_BASE: "change-me-to-something-random-this-is-really-important-change-it"
-      # uncomment enable sign ups, watch for spam!
+      # uncomment to enable sign ups, watch for spam!
       # REGISTRATION: "public"
     ports:
       # do not expose this publically!
       # always host from behind a reverse proxy with a properly configured certificate
-      - "4000:4000"
+      - "80:80"
     restart: always
     depends_on:
       - cannery-db