Test Drive Node.js

If you don’t test it, how do you know it works? Over the past few years, we have been compelled to write unit and integration tests for our applications--code that validates code--and it is these tests that change a one-off tool into a well-architected, robust, business-ready application. Yet, every new framework requires a new testing framework, so in this session, we will discuss testing frameworks for node.js. You will walk away with a solid understanding of how to write tests against your node.js applications and modules, leading to confidence that your work is business-ready.

Author:
Jay Harris
Problem Solver | Arana Software
jay@aranasoft.com | www.aranasoft.com
www.twitter.com/jayharris

Transcript

1. T E S T D R I V E N
2. Node.js is a platform built on Chrome's JavaScript runtime for easily building fast, scalable network applications. “ ” What is node.js?
4. basicFundamentals
5. packageManagement
6. is not an acronym
7. is an acronym National Association of Pastoral Musicians
8. github: install: isaacs/npm comes with node
9. npm install <package> localInstallation
10. npm install <package> --global globalInstallation -g or --global
11. npm install <package> --link dualInstallation
12. npm install <package> --save[-dev|-optional] dependencyReferences --save or --save-dev or --save-optional
13. npm install updateDependencies
14. testingNode.js
15. TDD is to coding style as yoga is to posture. Even when you're not actively practicing, having done so colors your whole life healthier.” j. kerr “
16. assertingCorrectness
17. var  assert  =  require('assert');
18. assert(value)            .ok(value)            .equal(actual,  expected)            .notEqual(actual,  expected)            .deepEqual(actual,  expected)            .notDeepEqual(actual,  expected)            .strictEqual(actual,  expected)            .notStrictEqual(actual,  expected)            .throws(block,  [error])            .doesNotThrow(block,  [error])            .ifError(value)
19. var assert = require('assert'); // Will pass assert.ok(true); // Will throw an exception assert.ok(false); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
20. var assert = require('assert'); // Will throw 'false == true' error assert.ok(typeof 'hello' === 'number'); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
21. $  node  test.js assert.js:104    throw  new  assert.AssertionError({                ^ AssertionError:  false  ==  true        at  Object.<anonymous>  (my-­‐test.js:7:8)        at  Module._compile  (module.js:449:26)        at  Object.Module._extensions..js  (module.js:467:10)        at  Module.load  (module.js:356:32)        at  Function.Module._load  (module.js:312:12)        at  Module.runMain  (module.js:487:10)        at  process.startup.processNextTick.process._tick... $  _
22. Chai Assertion Library
23. github: install: chaijs/chai npm install chai
24. isTrue,                      isFalse, isNull,                      isNotNull, isUndefined,            isDefined, isFunction,              isNotFunction, isArray,                    isNotArray, isBoolean,                isNotBoolean, isNumber,                  isNotNumber, isString,                  isNotString,                                    include,                                    lengthOf,                                    operator,                                    closeTo   isObject,                  isNotObject, typeOf,                      notTypeOf, instanceOf,              notInstanceOf, match,                        notMatch, property,                  notProperty, deepProperty,          notDeepProperty, propertyVal,            propertyNotVal, deepPropertyVal,    deepPropertyNotVal, additional assertions
25. var  assert  =  require('chai').assert;
26. var assert = require('chai').assert; // Will throw 'expected 'hello' to be a number' assert.isNumber('hello'); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
27. $  node  test.js expected  'hello'  to  be  a  number $  _
28. var chai = require('chai') , assert = chai.assert; chai.Assertion.includeStack = true; // Will throw and display stack assert.isNumber('hello'); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
29. testDriven
30. Exceptions alone are insufficient
31. $  node  my-­‐test.js assert.js:104    throw  new  assert.AssertionError({                ^ AssertionError:  false  ==  true        at  Object.<anonymous>  (my-­‐test.js:7:8)        at  Module._compile  (module.js:449:26)        at  Object.Module._extensions..js  (module.js:467:10)        at  Module.load  (module.js:356:32)        at  Function.Module._load  (module.js:312:12)        at  Module.runMain  (module.js:487:10)        at  process.startup.processNextTick.process._tick... $  _
32. We need a testing framework!
33. mocha simple, flexible, fun
34. mocha github: install: visionmedia/mocha npm install -g mocha
35. $  npm  install  -­‐g  mocha $  mkdir  test $  mocha        ✔  0  tests  complete  (1ms) $  
36. var  mocha  =  require('mocha');
37. suite('Testing  out  this  thing',  function()  {        test('should  do  stuff',  function()  {                //  Assertion  tests        }); }); tddSyntax
38. ./test/my-test.js var assert = require('chai').assert; suite('Assertions', function() { test('should pass on truthiness', function() { assert.ok(true); }); test('should fail on falsiness', function() { assert.ok(false); }); }); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
39. $  mocha  -­‐-­‐ui  tdd  -­‐-­‐reporter  spec    Assertions        ✓  should  pass  on  truthiness          1)  should  fail  on  falsiness    ✖  1  of  2  tests  failed:    1)  Assertions  should  fail  on  falsiness:              AssertionError:  false  ==  true            at  (stack  trace  omitted  for  brevity) $  _
40. groupedTests
41. suite('Testing  out  this  thing',  function()  {        suite('with  a  subset  of  this  other  thing',  function()  {                test('should  do  stuff',  function()  {                        //  Assertion  tests                });        }); }); groupSyntax
42. var assert = require('chai').assert; suite('Assertions', function() { suite('of truthiness', function() { test('should pass on true', function() { assert.isTrue(true); }); test('should pass on false', function() { assert.isFalse(false); }); }); suite('of type', function() { test('should pass on number', function() { assert.isNumber(5); }); }); }); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
43. $  mocha  -­‐-­‐ui  tdd  -­‐-­‐reporter  spec    Assertions        of  truthiness            ✓  should  pass  on  true              ✓  should  pass  on  false          of  type            ✓  should  pass  on  number      ✔  3  tests  complete  (6ms) $  _
44. pendingTests
45. suite('Testing  out  this  thing',  function()  {        suite('with  a  subset  of  this  other  thing',  function()  {                test('should  do  stuff  someday');        }); }); pendingSyntax
46. var assert = require('chai').assert; suite('Assertions', function() { suite('of truthiness', function() { test('should pass on true', function() { assert.isTrue(true); }); test('should pass on false', function() { assert.isFalse(false); }); }); suite('of type', function() { test('should pass on number', function() { assert.isNumber(5); }); test('should pass on object'); }); }); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
47. $  mocha  -­‐-­‐ui  tdd  -­‐-­‐reporter  spec    Assertions        of  truthiness            ✓  should  pass  on  true              ✓  should  pass  on  false          of  type            ✓  should  pass  on  number              -­‐  should  pass  on  object    ✔  4  tests  complete  (6ms)    •  1  test  pending $  _
48. setupTeardown
49. setup(); teardown();
50. suite('Testing  out  this  thing',  function()  {        setup(function(){                //  ...        };        suite('with  a  subset  of  this  other  thing',  function()  {                test('should  do  stuff',  function()  {                        //  Assertion  tests                });                teardown(function(){                        //  ...                };        }); }); setupTeardown
51. asynchronousTests
52. test('it  should  not  error',  function(done)  {        search.find("Apples",  done); }); asynchronousSyntax
53. test('it  should  not  error',  function(done)  {        search.find("Apples",  done); }); test('it  should  return  2  items',  function(done)  {        search.find("Apples",  function(err,  res)  {                if  (err)  return  done(err);                res.should.have.length(2);                done();        }); }); asynchronousSyntax
54. All Mocha functions accept this callback
55. suite('When searching for Apples', function(done) { setup(function(done){ items.save(['fiji apples', 'empire apples'], done); }); test('it should not error', function(done) { search.find("Apples", done); }); test('it should return 2 items', function(done) { search.find("Apples", function(err, res) { if (err) return done(err); res.should.have.length(2); done(); }); }); }); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
56. simplifyExecution
57. be nice to yourself: $  mocha  -­‐-­‐ui  tdd  -­‐-­‐reporter  spec should be simplified to $  make  test and $  npm  test
58. ./makefile # Makefile for sample module test: mocha --reporter spec --ui tdd .PHONY: test 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
59. ./makefile # Makefile for sample module test: mocha \ --reporter spec \ --ui tdd .PHONY: test 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
60. ./package.json { "name": "sample", "version": "0.1.0", "devDependencies": { "chai": "~1.2.0" }, "scripts": { "test": "make test" } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
61. $  make  test    Assertions        ✓  should  pass  on  truthiness          1)  should  fail  on  falsiness    ✖  1  of  2  tests  failed:    1)  Assertions  should  fail  on  falsiness:              AssertionError:  false  ==  true            at  (stack  trace  omitted  for  brevity) $  _
62. $  npm  test    Assertions        ✓  should  pass  on  truthiness          1)  should  fail  on  falsiness    ✖  1  of  2  tests  failed:    1)  Assertions  should  fail  on  falsiness:              AssertionError:  false  ==  true            at  (stack  trace  omitted  for  brevity) $  _
63. eliminate global dependency $  npm  install  mocha  -­‐-­‐link
64. test: @./node_modules/.bin/mocha \ --reporter spec \ --ui tdd .PHONY: test 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
65. update dev dependencies $  npm  install  mocha  -­‐-­‐save-­‐dev $  npm  install  chai    -­‐-­‐save-­‐dev
66. $  npm  install  mocha  -­‐-­‐save-­‐dev $  npm  install  chai    -­‐-­‐save-­‐dev $  git  diff  package.json   diff  -­‐-­‐git  a/package.json  b/package.json index  439cf44..3609bb9  100644 -­‐-­‐-­‐  a/package.json +++  b/package.json @@  -­‐1,5  +1,7  @@  {      "name":  "sample", -­‐    "version":  "0.1.0" +    "version":  "0.1.0", +    "devDependencies":  { +        "mocha":  "~1.4.0", +        "chai":  "~1.2.0" +    }  }
67. notificationSystems
68. mocha --slow <ms> slowThreshold -s <ms> or --slow <ms>
69. $  mocha  -­‐-­‐reporter  spec  -­‐-­‐slow  5    When  accessing  the  Ticket  API        with  valid  Morale  credentials,            and  with  a  project  that  exists,                getting  a  list  of  tickets                    ✓  should  return  without  an  error                      ✓  should  return  a  populated  array  (5ms)                    ✓  should  contain  a  task  or  bug  ticket                  adding  a  new  ticket                    ✓  should  return  without  an  error                      ✓  should  return  the  new  ticket  (11ms)  ✔  5  tests  complete  (22ms) $  _
70. mocha --watch continuousTesting -w or --watch
71. $  mocha  -­‐-­‐watch  ✔  5  tests  complete  (22ms)  ^  watching
72. Growl
73. mac: win: also: apple app store growlForWindows.com growlNotify
74. mocha --growl growlNotifications -G or --growl
75. ⌘S
76. test: @./node_modules/.bin/mocha \ --reporter spec \ --ui tdd watch: @./node_modules/.bin/mocha \ --reporter min \ --ui tdd \ --growl \ --watch .PHONY: test watch 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
77. behaviorDriven
78. suite('Test  this  thing',  function()  {        test('Do  stuff',  function()  {                //  Assertion  tests        }); }); describe('Testing  out  this  thing',  function()  {        it('should  do  stuff',  function()  {                //  Assertion  tests        }); }); bddSyntax tddSyntax
79. test: @./node_modules/.bin/mocha \ --reporter spec \ --ui bdd watch: @./node_modules/.bin/mocha \ --reporter min \ --ui bdd \ --growl \ --watch .PHONY: test 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
80. test: @./node_modules/.bin/mocha \ --reporter spec watch: @./node_modules/.bin/mocha \ --reporter min \ --growl \ --watch .PHONY: test 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
81. setupTeardown
82. before(); beforeEach(); after(); afterEach();
83. describe('Testing  out  this  thing',  function()  {        before(function(){                //  ...        };        describe('with  a  subset  of  that  thing',  function()  {                it('should  do  stuff',  function()  {                        //  Assertion  tests                });                afterEach(function(){                        //  ...                };        }); }); setupTeardown
84. There is no tdd equivalent to ‘each’
85. suite(); test(); setup(); teardown(); describe(); it(); before(); after(); beforeEach(); afterEach(); bddMethods tddMethods
86. expectAssertions
87. expectSyntax expect(person).to.be.an('object');        .with.property('age')        .that.is.a('number')        .that.equals(34); assert.isObject(person); assert.property(person,  "age"); assert.isNumber(person.age); assert.equals(person.age,  34); assertSyntax
88. var  expect  =  require('chai').expect;
89. assertionChains for readability
90. expect(person).to.exist        .and.be.an('object')        .with.property('age')        .that.is.to.exist        .and.is.a('number')        .and.equals(34);
91. .to .be .been .is .that .and .have .with syntaxSugar for readability
92. expect(person).to.exist        .and.be.an('object')        .with.property('age')        .that.is.to.exist        .and.is.a('number')        .and.equals(34);
93. expect(person).to.exist        .and.be.an('object')        .with.property('age')        .that.is.to.exist        .and.is.a('number')        .and.equals(34);
94. .property subjectChange from original object
95. expect(person)    .that.is.an('object')    .with.property('address')        .that.is.an('object')        .with.property('city')            .that.is.a('string')            .and.equals('Detroit')
96. shouldAssertions
97. person.should.be.an('object')        .with.property('age')        .that.is.a('number')        .that.equals(34); shouldSyntax assert.isObject(person); assert.property(person,  "age"); assert.isNumber(person.age); assert.equals(person.age,  34); assertSyntax
98. var  should  =  require('chai').should();
99. var  chai      =  require('chai')    ,  expect  =  chai.expect    ,  should  =  chai.should();
100. assertionChains same as expect style* except for existence
101. expect(foo).to.not.exist; expect(bar).to.exist; should.not.exist(foo); should.exist(foo);
102. skippedTests
103. describe('Testing  out  this  thing',  function()  {        it.skip('should  be  skipped',  function()  {                //  Assertion  tests        }); }); describe.skip('This  entire  suite  will  be  skipped',  function()  {        it('should  do  stuff',  function()  {                //  Assertion  tests        }); }); skipSyntax
104. describe('Assertions', function() { describe('of truthiness', function() { it('should pass on truthiness', function() { assert.isTrue(true); }); it('should pass on falsiness', function() { assert.isFalse(false); }); }); describe('of type', function() { it.skip('should pass on number', function() { assert.isNumber(5); }); it('should pass on object'); }); }); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
105. $  make  test    Assertions        of  truthiness            ✓  should  pass  on  truthiness              ✓  should  pass  on  falsiness          of  type            -­‐  should  pass  on  number              -­‐  should  pass  on  object    ✔  4  tests  complete  (6ms)    •  2  test  pending $  _
106. Skip is available in bdd only
107. mockingObjects
108. JavaScript ships with a mocking framework ...it’s called JavaScript
109. var me = {firstName: 'Jay' , lastName: 'Harris' , getFullName: function() { return this.firstName + ' ' + this.lastName; }}; // Returns 'Jay Harris' me.getFullName(); me.getFullName = function() { return 'John Doe'; }; // Returns 'John Doe' me.getFullName(); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
110. nock HTTP Mocking Library
111. nock github: install: flatiron/nock npm install nock
112. var http = require('http'); var reqOptions = { host: 'api.twitter.com', path: '/1/statuses/user_timeline.json?' + 'screen_name=jayharris' }; var resCallback = function(res) { var responseData = ''; res.on('data', function(chunk) { responseData += chunk; }); res.on('end', function() { console.log(responseData); }); }; http.request(reqOptions, resCallback).end(); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
113. var nock = require('nock'); var twitter = nock('http://api.twitter.com') .get('/1/statuses/user_timeline.json?'+ 'screen_name=jayharris') .reply(200, "This worked"); // Returns "This worked" http.request(reqOptions, resCallback).end(); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
114. // Returns live Twitter data http.request(reqOptions, resCallback).end(); var nock = require('nock'); var twitter = nock('http://api.twitter.com') .get('/1/statuses/user_timeline.json?'+ 'screen_name=jayharris') .reply(200, "This worked"); // Returns "This worked" http.request(reqOptions, resCallback).end(); // Returns live Twitter data http.request(reqOptions, resCallback).end(); 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
115. nock nock.recorder.rec(  ); nock.recorder.play(  );
116. Spies, Stubs, & Mocks Sinon.js
117. github: install: cjohansen/Sinon.JS npm install sinon Sinon.js
118. browserTesting
119. Fast, headless browser Zombie.js
120. github: install: assaf/zombie npm install zombie Zombie.js
121. loadTesting
122. Performance Suite nodeload
123. github: install: benschmaus/nodeload npm install nodeload nodeload
124. activelyPractice
125. Color your whole life healthier
126. jay harris jay@aranasoft.com #testdrivennode @jayharris P R E S I D E N T