iss_node/test/index_test.js

A module that returns a readable stream based on the position of the International Space Station

var assert = require("assert");
var SpaceStream = require('../lib/index.js');
var stream = require('stream');

describe('SpaceStream', function () {

  describe('identity', function () {
    var testerStream1 = new SpaceStream(25554, 59);

    it('should be a function', function () {
      assert.equal(typeof SpaceStream, 'function');
    });

    it('should be subclassed from stream.Readable', function () {
      assert.equal(testerStream1 instanceof stream.Readable, true);
    });
  });

  describe('userErrorCases', function () {
    it('should throw an error if no arguments are provided', function () {
      assert.throws(function () {
        var a = new SpaceStream();
      }, Error);
    });
    it('should throw an error if a non-number Sattelite ID is provided', function () {
       assert.throws(function () {
        var b = new SpaceStream('ISS', 30);
      }, Error);
    });
    it('should throw an error if a non-number frequency is provided', function () {
      assert.throws(function () {
        var c = new SpaceStream(255544, 'Often');
      }, Error);
    });
    it('should throw an error if an out-of-range frequency is provided', function () {
      assert.throws(function () {
        var d = new SpaceStream(255544, 61);
      }, Error);
    });
  });

  describe('expected data retrieval behavior', function () {
    this.timeout(4000);

    var receivedData = false;
    var e = new SpaceStream(25544, 55);
    e.setEncoding('utf8');

    it('should emit "readable" events when data is available to be read', function (done) {
     e.on('readable', function getData(){
        receivedData = e.read();
        e.removeListener('readable', getData);
        done();
        assert.ok(receivedData);
        });
    });
    it('should return JSON-stringified ISS location data from wheretheiss.at API', function(){
      receivedData = JSON.parse(receivedData);
      assert.equal(receivedData.name, 'iss');
    });
  });

  describe('timing', function(){

    it('should not receive data before data is expected', function(done){
      this.timeout(3000);

      var timesDataReceived = 0;
      var f = new SpaceStream(25544, 30);
      f.on('readable', function(){
        timesDataReceived++;
      });
      setTimeout(function(){
        assert.equal(timesDataReceived, 0);
        done();
        }, 1900);
      });

    it('should receive chunks within the user-described frequency, discounting I/O delay', function(done){
      this.timeout(3000);

      var timesDataReceived = 0;
      var g = new SpaceStream(25544, 59);
      g.on('readable', function(){
        timesDataReceived++;
      });

      setTimeout(function(){
        assert(timesDataReceived >= 1);
        done();
      }, 2000);
    });
  });

  describe('stream termination', function(){

    it('should have a stop method that emits an "end" event, stopping an active stream', function(){

      var ended = false;
      var h = new SpaceStream(25544, 30);
      h.on('end', function(){
        ended = true;
        assert(ended);
      });
      h.stopStream();
    });
  });
});