Testing API requests on localhost

I'm using Mocha and Chai to develop testing scripts for my API in Node.js. I have an endpoint called /measurements. This endpoint should return statusCode 200.

Here's how I trying to reach my goal:

var request = require("request");
var chai = require("chai");
var expect = chai.expect;

    var should = require("should");
    var request = require("request");
    var chai = require("chai");
    var expect = chai.expect;
    var urlBase = "localhost:3000";


    describe("Teste monitora-sec", function () {

        it("Deve receber as medições", function (done) {
            request.get('localhost:3000/measurements')
                .expect(200)
                .end(function (err, res) {
                    expect(res.body).to.have.lengthOf(506);
                    done(err);
                });
        });
    });

When I run mocha on gitbash, I get this error:

Teste monitora-sec
    1) Deve receber as medições


0 passing (34ms)
1 failing

1) Teste monitora-sec
    Deve receber as medições:
    Error: Invalid protocol: localhost:
    at Request.init (node_modules\request\request.js:458:31)
    at new Request (node_modules\request\request.js:127:8)
    at request (node_modules\request\index.js:53:10)
    at Function.get (node_modules\request\index.js:61:12)
    at Context.<anonymous> (test\measurement.spec.js:11:17)

What am I doing wrong?