Make persistent theme volume optional

.env.sample

@@ -8,6 +8,11 @@ LETS_ENCRYPT_ENV=production
 ADMIN_USERNAME=admin
 WELCOME_THEME=keycloak
 
+COMPOSE_FILE="compose.yml"
+
 SECRET_DB_ROOT_PASSWORD_VERSION=v1
 SECRET_DB_PASSWORD_VERSION=v1
 SECRET_ADMIN_PASSWORD_VERSION=v1
+
+# Enable persistent theme volume, if you want to apply a custom theme
+#COMPOSE_FILE="$COMPOSE_FILE:compose.theme.yml"

compose.theme.yml

@@ -0,0 +1,7 @@
+services:
+  app:
+    volumes:
+      - "themes:/opt/keycloak/themes"
+
+volumes:
+  themes:

compose.yml

@@ -30,7 +30,6 @@ services:
     #   retries: 10
     #   start_period: 1m
     volumes:
-      - "themes:/opt/keycloak/themes"
       - "providers:/opt/keycloak/providers"
     depends_on:
       - mariadb
@@ -91,5 +90,4 @@ secrets:
 
 volumes:
   mariadb:
-  themes:
   providers: