Here is an example of using Mocha programmatically for the integration test/ API test

index.js

// out scenario test write here

const chalk = require('chalk')
const expect = require('chai').expect
const request = require('./../request')

describe(chalk.cyanBright.bold('#GET: request to /user'), function () {
  let auth = null
  let user = []
  before(async function () {
    this.timeout(10000) // 10 second
    auth = await request.login({username: 'user', password: 'password'})
    // create user before runing scenario test
    user = await request.postUser(auth, {name: 'John Doe'})
  })

  after(function (done) {
    this.timeout(10000) // 10 second
    request.deleteUser(auth, user.id) // delete user after runing scenario test
    done()
  })
  
  describe('valid request', function () {
    describe('should return users resource with status code 200', function () {
      let response = null
      it('status code is 200', async function () {
        response = await request.getUser(auth, '?status=active')
        expect(response).to.have.property('status', 200)
      })
    })
    // describe() other positive test
  })
  
  describe('invalid request', function () {
    describe('should return property message with status code 400', function () {
      let response = null
      it('status code is 400', async function () {
        response = await request.getUser(null, '?status=null')
        expect(response).to.have.property('status', 400)
      })
    })
    // describe() other negative test
  })
}

package.json

{
  "scripts": {
    "mocha-node-test": "node ./tests/api/index.js",
    "test": "npm run mocha-node-test"
  },
  "dependencies": {},
  "devDependencies": {
    "chai": "^3.5.0",
    "chalk": "^2.4.1",
    "mocha": "^5.2.0",
    "supertest": "^3.1.0"
  },
  "standard": {
    "env": [
      "mocha",
      "chai"
    ]
  }
}

request.js

// Our event request api testing
const request = require('supertest')
const headers = {
  'Content-type': 'application/json',
  'x-api-version': '0.1',
  'token': ''
}
const baseurl = 'http://localhost:3000/api'

module.exports = {
  /**
   * Request post for user login
   * @return user object with token
   */
  login: async function (query) {
    let response = await request(baseurl).post('/user/login/').send(query);
    return response;
  },
  
  /**
   * Request get for retrive users
   * @return user list
   */
  getUser: async function (auth = null, query) {
    headers.token = auth ? auth.body.token : '';
    let response = await request(baseurl).get('/user' + query).set(headers);
    return response;
  },
  
  /**
   * Request post for create user
   * @return user object
   */
  postUser: async function (auth = null, query) {
    headers.token = auth ? auth.body.token : '';
    let response = await request(baseurl).post('/user').send(query).set(headers);
    return response;
  },
  
  /**
   * Request delete for remove user
   * @return message object
   */
  deleteUser: async function (auth = null, id) {
    headers.token = auth ? auth.body.token : '';
    let response = await request(baseurl).delete('/user/' + id).set(headers);
    return response;
  }
}

test.js

// registry file Node.js  API test
const Mocha = require('mocha')
const mocha = new Mocha() // Instantiate a Mocha instance.

var testsDir = [
  './tests/api/users/'
]

for (var i = 0; i < testsDir.length; i++) {
  mocha.addFile(testsDir[i])
}

// Run the tests.
mocha.run(function (failures) {
  // exit with non-zero status if there were failures
  process.exitCode = failures ? -1 : 0
})