Easy way to write Unit Test cases of Node.Js

Initially, I used to think why my Architect is asking for writing test cases it's just wasting of time, But later I realised that it's important to write test cases along with the application features . Because it will give you the confidence in each iteration of new build or release.

I have seen the impact of not writing proper test cases in one of my projects, As the developer is always hurrying for completing user stories or features. As I have analyzed we could have stopped at least 40% bugs if we would have written the proper unit test cases.

So let's see the easy way to write Node.Js unit test cases Using Mocha and Chai library

Mocha is a test runner environment

Chai is an assertion library

1.Create node.js project using:

npm init

Install dependencies

npm i mocha -g (global install)

npm i chai mocha request -D (local install)

Create app.js file and write the below code.

const express = require('express');
const app = express();
app.get('/ping', (req, res)=>{
  res.status(200);
  res.json({message: 'pong'});
});
app.listen(8080, ()=>{
  console.log('Waw Server is running : 8080')
});

create a test folder and add app.test.js file and write the below code.

var expect = require('chai').expect;
var request = require('request');
describe('app rest api testing', () => {
  it('/ping status code', (done) => {
    request('http://localhost:8080/ping', (err, result, body) => {
    expect(result.statusCode).to.equal(200);
    expect(body).to.equal(JSON.stringify({"message":"pong"}));
    done();
  });
 });
});