Updating to reflect changes in the Example Voting App

Updated `docker-compose.yml` file to reflect current status in the Example Voting App.

beginner/chapters/votingapp.md

@@ -50,51 +50,61 @@ Now, run your application. To do that, we'll use [Docker Compose](https://docs.d
 version: "2"
 
 services:
-  voting-app:
-    build: ./voting-app/.
+  vote:
+    build: ./vote
+    command: python app.py
     volumes:
-     - ./voting-app:/app
+     - ./vote:/app
     ports:
       - "5000:80"
     networks:
       - front-tier
       - back-tier
 
-version: "2"
-
-services:
-  vote:
-    build: ./vote
-    command: python app.py
+  result:
+    build: ./result
+    command: nodemon --debug server.js
     volumes:
-     - ./vote:/app
+      - ./result:/app
     ports:
-      - "5000:80"
+      - "5001:80"
+      - "5858:5858"
+    networks:
+      - front-tier
+      - back-tier
+
+  worker:
+    build: ./worker
+    networks:
+      - back-tier
 
   redis:
     image: redis:alpine
+    container_name: redis
     ports: ["6379"]
-
-  worker:
-    build: ./worker
+    networks:
+      - back-tier
 
   db:
     image: postgres:9.4
-
-  result:
-    build: ./result
-    command: nodemon --debug server.js
+    container_name: db
     volumes:
-      - ./result:/app
-    ports:
-      - "5001:80"
-      - "5858:5858"
+      - "db-data:/var/lib/postgresql/data"
+    networks:
+      - back-tier
+
+volumes:
+  db-data:
+
+networks:
+  front-tier:
+  back-tier:
 ```
 
 This Compose file defines
 
-- A voting-app container based on a Python image
-- A result-app container based on a Node.js image
+- A vote container based on a Python image
+- A result container based on a Node.js image
 - A redis container based on a redis image, to temporarily store the data.
 - A .NET based worker app based on a .NET image
 - A Postgres container based on a postgres image