well it works. mocha + chai + chai-http

foo.js

/*
  "devDependencies": {
    "chai": "^3.5.0",
    "mocha": "^3.1.2",
    "chai-http": "^3.0.0"
  }
*/
"use strict"

let chai = require('chai');
let chaiHttp = require('chai-http');
let server = require('../src/main');

let should = chai.should();

chai.use(chaiHttp);

describe("Basic tests", () => {
  it("it should get the app status", (done) => {
    chai.request(server.app)
      .get('/status')
      .end((err, res) => {
        res.should.have.status(200);
        res.text.should.be.eql("ONLINE");
        done();
      });
  });
});