added express-rate-limit middleware to Web UI

web/server.js

@@ -1,11 +1,20 @@
 const compression = require('compression');
 const express = require('express');
-const bodyParser = require('body-parser');
 const path = require('path');
 const app = express();
 app.use(compression());
 app.disable('x-powered-by');
 app.use(express.static(path.join(__dirname, 'build')));
+
+// set up rate limiter: maximum of five requests per minute
+var RateLimit = require('express-rate-limit');
+var limiter = new RateLimit({
+  windowMs: 1*60*1000, // 1 minute
+  max: 5 // limit each IP to 5 requests per windowMs
+});
+// apply rate limiter to all requests
+app.use(limiter);
+
 // need to declare a "catch all" route on your express server
 // that captures all page requests and directs them to the client
 // the react-router do the route part