Added rate limiter.

Author: meetDeveloper

app.js

@@ -1,6 +1,6 @@
 const { JSDOM } = require('jsdom'),
     express = require('express'),
-    app = express(),
+    rateLimit = require("express-rate-limit"),
 
     utils = require('./modules/utils.js'),
     errors = require('./modules/errors.js'),
@@ -10,6 +10,12 @@ const { JSDOM } = require('jsdom'),
     { DOMParser } = new JSDOM().window,
     parser = new DOMParser(),
 
+    app = express(),
+    limiter = rateLimit({
+        windowMs: 5 * 60 * 1000, // 5 minutes
+        max: 450 // limit each IP to 450 requests per windowMs
+    }),
+
     // Versions
     V1 = 'v1',
     V2 = 'v2',
@@ -58,6 +64,8 @@ function handleError (error = {}) {
 
 app.set('trust proxy', true);
 
+app.use(limiter);
+
 app.get('/api/:version/entries/:language/:word', async (req, res) => {
     let { word, language, version } = req.params,
         include = _.reduce(_.get(req.query, 'include', '').split(','), (accumulator, current) => {

package.json

@@ -11,6 +11,7 @@
   "license": "ISC",
   "dependencies": {
     "express": "^4.17.1",
+    "express-rate-limit": "^5.3.0",
     "jsdom": "^15.2.1",
     "lodash": "^4.17.20",
     "node-fetch": "^2.6.0",