Mocha Supertest Express: app.address is not a function even if I exported correctly app.

Good morning. I’m still considering quite a newbe in Node.Js since very often I get into problems that with a bit of searching I figure out how to solve. Except this.

This is my ./src/app.js file:

const express = require('express');
const bodyParser = require('body-parser');
const ENV = require('./env');
const request = require('supertest');
const app = express();

app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));

app.get('/', (req, res) => {
    res.json({
        service: 'user-service',
    });
});

// This works correctly
const req = request(app);
req
    .get('/')
    .expect('Content-Type', /json/)
    .expect(JSON.stringify({
        service: 'user-service'
    }))
    .expect(200)
    .end(function (err, res) {
        if (err) throw err;
    });

// I tired in both ways
module.exports = Object.assign({}, app);
// module.exports = app;

This is my ./index.js file:

const app = require('./src/app');
const ENV = require('./src/env');

app.listen(3000, () => {
    console.log(`Server started on port ${ENV.port}`);
});

module.exports = app;

This is my ./test/test.js file:

const request = require('supertest');
const app = request('../src/app');
/*
  using request('http://localhost:3000') works correctly
  but i know it's not the best way to setup a testing environment
*/
//const req = request('http://localhost:3000'); 
const req = request(app);

describe('Integration test exaple', function() {
    it('get /', function(done) {
        req
        .get('/')
        .expect('Content-Type', /json/)
        .expect(JSON.stringify({ service: 'user-service' }))
        .expect(200, done);
    });
});

I tried to require app both from app.js and index.js but the result it’s the same:

>> mocha ./test/test

  Integration test exaple
    1) get /

  0 passing (9ms)
  1 failing

  1) Integration test exaple
       get /:
     TypeError: app.address is not a function
      at Test.serverAddress (node_modules\supertest\lib\test.js:55:18)
      at new Test (node_modules\supertest\lib\test.js:36:12)
      at Object.obj.(anonymous function) [as get] (node_modules\supertest\index.js:25:14)
      at Context.<anonymous> (test\integration.test.js:12:10)

Thanks in advance for any kind of help!

[jonathansamines]

@Danver97 Not sure how I didn’t notice that before but the problem is that you are using the function request to try to require your app in your tests. You should use require instead.

See: https://github.com/Danver97/user-service/blob/master/test/integration.test.js#L4

[Danver97]

@jonathansamines It’s pretty curious: I checked again and using module.exports = app doesn’t work, BUT in another project it’s working fine… Also using the result of app.listen doesn’t work. I can’t understand why…