fix: make sure server work

Author: amazingshellyyy

README.md

@@ -94,11 +94,16 @@ $ npm run deploy:heroku
 
 ### After creating heroku
 
+if using webpack:
 remember to update the file of [client/webpack.prod.js](https://github.com/amazingandyyy/mern/blob/master/client/webpack.prod.js)
 ```javascript
  'API_URI': JSON.stringify('https://your-super-amazing-heroku-app.herokuapp.com')
 ```
-
+if using parcel
+remember to update the file of [client/.env.production](https://github.com/amazingandyyy/mern/blob/master/client/.env.production.js)
+```
+ REACT_APP_API_URI=https://your-super-amazing-heroku-app.herokuapp.com
+```
 # Dependencies(tech-stacks)
 Client-side | Server-side
 --- | ---

client/.env.production

@@ -0,0 +1,2 @@
+REACT_APP_API_URI=https://mern-amazingandyyy.herokuapp.com
+NODE_ENV=production

server/src/index.js

@@ -23,7 +23,7 @@ mongoose.Promise = global.Promise;
 
 // App Setup
 app.use(cors({
-    origin: ['https://www.amazingandyyy.com', 'http://localhost:3000']
+    origin: ['https://www.amazingandyyy.com', 'http://localhost:3000', 'http://localhost:1234']
 }));
 app.use(morgan('dev'));
 app.use(express.json())