add CORS configuration

Author: tienbku

package.json

@@ -18,6 +18,7 @@
   "license": "ISC",
   "dependencies": {
     "body-parser": "^1.19.0",
+    "cors": "^2.8.5",
     "express": "^4.17.1",
     "mysql2": "^2.0.2",
     "sequelize": "^5.21.2"

server.js

@@ -1,8 +1,15 @@
 const express = require("express");
 const bodyParser = require("body-parser");
+const cors = require("cors");
 
 const app = express();
 
+var corsOptions = {
+  origin: "http://localhost:8081"
+};
+
+app.use(cors(corsOptions));
+
 // parse requests of content-type - application/json
 app.use(bodyParser.json());