add unit tests

app.js

@@ -7,6 +7,7 @@
 // This application uses express as its web server
 // for more info, see: http://expressjs.com
 var express = require('express');
+const message = require('./utils');
 
 // cfenv provides access to your Cloud Foundry environment
 // for more info, see: https://www.npmjs.com/package/cfenv
@@ -25,5 +26,5 @@ var appEnv = cfenv.getAppEnv();
 app.listen(appEnv.port, '0.0.0.0', function() {
 
 	// print a message when the server starts listening
-  console.log("server starting on " + appEnv.url);
+  console.log(message.getWelcomeMessage() + appEnv.url);
 });

package.json

 {
 	"name": "HelloWorldNodeApp",
 	"version": "0.0.1",
-        "private": true,
+	"private": true,
 	"scripts": {
-		"start": "node app.js"
+		"start": "node app.js",
+		"test-unit": "mocha test/unit-test.js --reporter json --reporter-options output=test/unit-test.json | tee test/unit-test.json"
 	},
 	"dependencies": {
 		"express": "4.17.x",
@@ -12,5 +13,10 @@
 	"repository": {},
 	"engines": {
 		"node": "10.x || 12.x"
-	} 
+	},
+	"devDependencies": {
+		"chai": "^4.2.0",
+		"mocha": "^7.0.1",
+		"nyc": "*"
+	}
 }

test/run-tests.sh

+#!/bin/bash
+# set -x
+npm install
+npm run test-unit
+FILE_LOCATIONS="./test/unit-test.json"
+TEST_TYPES="unittest"
\ No newline at end of file

test/unit-test.js

+const assert = require('assert');
+const message = require('../utils');
+describe('Message Test', () => {
+ it('Welcome Message', () => {
+        assert.strictEqual(message.getWelcomeMessage(), "server starting on ");
+    });
+});
\ No newline at end of file

utils.js

+
+
+  
+const welcomeMessage = "server starting on ";
+
+const getWelcomeMessage = () => {
+    return welcomeMessage;
+};
+
+exports.getWelcomeMessage = getWelcomeMessage;
\ No newline at end of file