Set different networks for db-backend and backend-proxy

Signed-off-by: Anca Iordache <anca.iordache@docker.com>

nginx-flask-mysql/docker-compose.yaml

@@ -1,27 +1,40 @@
 version: "3.7"
 services:
-  backend:
-    build: backend
-    secrets:
-      - db-password
-    ports:
-      - 5000:5000
   db:
-    environment:
-      MYSQL_DATABASE: example
-      MYSQL_ROOT_PASSWORD_FILE: /run/secrets/db-password
     image: mysql:8.0.19
+    command: '--default-authentication-plugin=mysql_native_password'
     restart: always
     secrets:
     - db-password
     volumes:
     - db-data:/var/lib/mysql
+    networks:
+      - backnet
+    environment:
+      - MYSQL_DATABASE=example
+      - MYSQL_ROOT_PASSWORD_FILE=/run/secrets/db-password
+  backend:
+    build: backend
+    restart: always
+    secrets:
+    - db-password
+    ports:
+    - 5000:5000
+    networks:
+    - backnet
+    - frontnet
   proxy:
     build: proxy
+    restart: always
     ports:
-    - 8080:80
+    - 80:80
+    networks:
+      - frontnet
 volumes:
-  db-data: {}
+  db-data:
 secrets:
   db-password:
     file: db/password.txt
+networks:
+  backnet:
+  frontnet: