Behavior & Specification Driven Development in PHP - #OpenWest

Let's move past the basics of test driven development and into the amazing world of specification-driven development and behavior-driven development. Using the tools PHPSpec and Behat, I'll show how you can not only build test coverage but also generate much of your code for you. In this talk, we’ll see what PHPSpec & Behat can do with a series of examples and use cases.

Transcript

1. Behavior & Specification Driven Development in PHP Presented by Joshua Warren
2. OR:
3. I heard you like to code, so let’s write code that writes code while you code.
5. About Me
6. PHP Developer Working with PHP since 1999
7. Founder & CEO Founded Creatuity in 2008 PHP Development Firm Focused on the Magento platform Tink, a Creatuity shareholder
8. JoshuaWarren.com @JoshuaSWarren
9. IMPORTANT! • joind.in/14065 • Download slides • Post comments • Leave a rating!
10. What You Need To Know ASSUMPTIONS
11. Today we assume you’re a PHP developer.
12. That you are familiar with test driven development.
13. And that you’ve at least tried PHPUnit, Selenium or another testing tool.
14. BDD - no, the B does not stand for beer, despite what a Brit might tell you Behavior Driven Development
15. Think of BDD as stepping back a level from TDD.
16. Graphic thanks to BugHuntress
17. TDD generally deals with functional units.
18. BDD steps back a level to consider complete features.
19. In BDD, you write feature files in the form of user stories that you test against.
20. BDD uses a ubiquitous language - basically, a language that business stakeholders, project managers, developers and our automated tools can all understand.
21. Sample Behat Feature File Feature: Laravel Test
 In order to demonstrate Laravel and Behat
 As a user
 I need to be able to visit the homepage of a new Laravel app
 
 Scenario: Homepage
 Given I am on the homepage
 Then I should see "Laravel 5"

22. Behat
23. We implement BDD in PHP with a tool called Behat
24. Behat is a free, open source tool designed for BDD and PHP
25. behat.org
26. SpecBDD - aka, Testing Tongue Twisters Specification Behavior Driven Development
27. Before you write a line of code, you write a specification for how that code should work
28. Focuses you on architectural decisions up-front
29. PHPSpec
30. Open Source tool for specification driven development in PHP
31. www.phpspec.net
32. Why Use Behat and PHPSpec?
33. These tools allow you to focus exclusively on logic
34. Helps build functional testing coverage
35. Guides planning and ensuring that all stakeholders are in agreement
36. Let’s Build Something!
37. … what we’re building …
38. Setting up Our Project
39. Setup a Laravel 5 project
40. Run composer require —dev behat/behat behat/mink behat/mink-extensions laracasts/behat-laravel-extension phpspec/phpspec benconstable/phpspec-laravel
41. Run: vendor/bin/behat —init
42. Create /behat.yaml default:
 extensions:
 Laracasts\Behat: ~
 Behat\MinkExtension\ServiceContainer\MinkExtension:
 default_session: laravel
 laravel: ~

43. Create /phpspec.yaml suites: main: namespace: App psr4_prefix: App src_path: app extensions: - PhpSpec\Laravel\Extension\LaravelExtension
44. Features
45. features/fitbit.feature Feature: Fitbit Integration
 In order to obtain Fitbit data
 As a user
 I need to be able to authenticate with Fitbit
 Scenario: Not yet authenticated
 Given I am not logged in as “josh@creatuity.com” When I go to "/fitbit/"
 Then I should see "Please authenticate"
 

46. vendor/bin/behat —append-snippets Scenario: Not yet authenticated:6 Given I am not logged in as “josh@creatuity.com When I go to "/fitbit/" Then I should see "Please authenticate" 1 scenario (1 undefined) 3 steps (1 undefined, 2 skipped) 0m0.48s (11.00Mb) u features/bootstrap/FeatureContext.php - `I am not logged in as` definition added
47. Behat’s written code for us!
48. /features/bootstrap/FeatureContext.php /**
 * @Given I am not logged in as :arg1
 */
 public function iAmNotLoggedInAs($arg1)
 {
 throw new PendingException();
 }

49. Behat writes just enough to get us show us where to add our logic.
50. Behat expects us to add logic to this function to detect the user is not logged in.
51. Before we do that, let’s finish out our feature file.
52. features/fitbit.feature continued Scenario: I have authenticated
 Given I am logged in as “josh@creatuity.com” When I go to "/fitbit/"
 Then I should see "Welcome back"
 Scenario: I have sleep data
 Given I am logged in as “josh@creatuity.com”
 When I go to "/fitbit/sleep/"
 Then I should see "Sleep Report"

53. Run vendor/bin/behat —append-snippets one more time
54. Now, let’s fill in the logic Behat needs us to add.
55. /features/bootstrap/FeatureContext.php /**
 * @Given I am not logged in as :email
 */
 public function iAmNotLoggedInAs($email)
 {
 // We completely log out
 // Destroy the previous session
 if (Session::isStarted()) {
 Session::regenerate(true);
 } else {
 Session::start();
 }
 }

56. /features/bootstrap/FeatureContext.php public function iAmLoggedInAs($email)
 {
 // Destroy the previous session
 if (Session::isStarted()) {
 Session::regenerate(true);
 } else {
 Session::start();
 }
 
 // Login the user and since the driver and this code now
 // share a session this will also login the driver session
 $user = User::where('email', $email)->firstOrFail();
 Auth::login($user);
 
 // Save the session data to disk or to memcache
 Session::save();
 
 // Hack for Selenium
 // Before setting a cookie the browser needs to be launched
 if ($this->getSession()->getDriver() instanceof \Behat\Mink\Driver\Selenium2Driver) {
 $this->visit('login');
 }
 
 // Get the session identifier for the cookie
 $encryptedSessionId = Crypt::encrypt(Session::getId());
 $cookieName = Session::getName();
 
 // Set the cookie
 $minkSession = $this->getSession();
 $minkSession->setCookie($cookieName, $encryptedSessionId);
 }
57. We run vendor/bin/behat once more
58. vendor/bin/behat … Scenario: I have sleep data Given I am logged in as "josh@creatuity.com" When I go to "/fitbit/sleep/" Then I should see "Sleep Report" The text "Sleep Report" was not found anywhere in the text of the current page. (Behat\Mink\Exception\ResponseTextException) --- Failed scenarios: features/fitbit.feature:6 features/fitbit.feature:11 features/fitbit.feature:16
59. A perfect failure!
60. These failures show us that Behat is testing our app properly, and now we just need to write the application logic.
61. Specifications
62. Now we write specifications for how our Fitbit class should work.
63. These specifications should provide the logic to deliver the results that Behat is testing for.
64. vendor/bin/phpspec describe Fitbit Specification for Fitbit created in <project root>/spec/ FitbitSpec.php
65. PHPSpec generates a basic spec file for us
66. spec/FitbitSpec.php namespace spec;
 
 use PhpSpec\ObjectBehavior;
 use Prophecy\Argument;
 
 class FitbitSpec extends ObjectBehavior
 {
 function it_is_initializable()
 {
 $this->shouldHaveType('Fitbit');
 }
 }

67. This default spec tells PHPSpec to expect a class named Fitbit.
68. Now we add a bit more to the file so PHPSpec will understand what this class should do.
69. spec/FitbitSpec.php continued function it_connects_to_fitbit($email)
 {
 $this->connect($email)->shouldReturn('Success');
 }
 
 function it_returns_sleep_data($email)
 {
 $this->sleepData($email)->shouldReturn([8, 8, 8, 8, 8]);
 }

70. Now we run PHPSpec once more…
71. vendor/bin/phpspec run 10 ! is initializable (142ms) class Fitbit does not exist. 15 ! connects to fitbit (100ms) class Fitbit does not exist. 20 ! returns sleep data class Fitbit does not exist. ---- broken examples Fitbit 10 ! is initializable (142ms) class Fitbit does not exist. Fitbit 15 ! connects to fitbit (100ms) class Fitbit does not exist. Fitbit 20 ! returns sleep data class Fitbit does not exist. 1 specs 3 examples (3 broken)
72. Lots of failures…
73. But wait a second - PHPSpec prompts us!
74. Do you want me to create `Fitbit` for you? [Y/n]
75. PHPSpec will create the class and the methods for us!
76. This is very powerful with frameworks like Laravel and Magento, which have PHPSpec plugins that help PHPSpec know where class files should be located.
77. Fitbit.php - class Fitbit { function connect($email)
 {
 // TODO: write logic here
 }
 
 function sleepData($email)
 {
 // TODO: write logic here
 }

78. And now, the easy part…
79. Implementation
80. Implement logic in the new Fitbit class in the locations directed by PHPSpec
81. Tie that logic into views in our application.
82. Once we’re done with the implementation, we move on to…
83. Testing
84. Once we’re done, running phpspec run should return green
85. Once phpspec returns green, run behat, which should return green as well
86. We now know that our new feature is working correctly without needing to open a web browser
87. PHPSpec gives us confidence that the application logic was implemented correctly.
88. Behat gives us confidence that the feature is being displayed properly to users.
89. Success!
90. The purpose of this talk is to get you hooked on Behat & PHPSpec and show you how easy it is to get started.
91. Behat and PHPSpec are both powerful tools
92. PHPSpec can be used at a very granular level to ensure your application logic works correctly
93. Next week, setup Behat and PHPSpec on one of your projects and take it for a quick test by implementing one short feature.
94. Keep In Touch! • joind.in/14065 • @JoshuaSWarren • JoshuaWarren.com