Driving Your Domain by Examples - London Magento Meetup

How to use Gherkin scenarios and Behat to drive your development into modelling the problem you're trying to solve rather than an arbitrary and possibly inadequate solution.
Slides for the version of the talk delivered at the London Magento user group meetup on May 25, 2016.

Related Links:
- Introducing Modelling by Example http://stakeholderwhisperer.com/posts/2014/10/introducing-modelling-by-example
- Named Constructors in PHP http://verraes.net/2014/06/named-constructors-in-php/
- An Introduction to BDD from Konstantin Kudryashov https://www.youtube.com/watch?v=njcHzGYv7nI

Transcript

1. Sample Title London Magento User Group Driving your domain by examples
2. London Magento User Group Marco Lopes Technical Team Lead - Session Digital @mpmlopes Inviqa Group Marco Lopes
3. A familiar scenario…
4. Everything changes
5. PANIC! NOW!
6. Why does it happen?
7. Short feedback cycle
8. Short feedback cycle AKA Agile
9. Can we do more?
10. Shorten feedback cycle
11. BDD
12. Behat & PHPSpec
13. Modelling by Example
14. Domain Suite
15. Scenario: Paying with a credit card
 Given AwesomePay has credit card payments enabled
 When I fill the credit card number with 4444333322221111 And I fill the expiry date with ”04/2018” And I fill the CCV with 123 And the credit card has unlimited funds on payment gateway
 And I press place order button
 Then the payment should be accepted And the magento order status should be ”processing”
16. Scenario: Paying with a credit card
 Given AwesomePay has credit card payments enabled
 When I fill the credit card number with 4444333322221111 And I fill the expiry date with ”04/2018” And I fill the CCV with 123 And the credit card has unlimited funds on payment gateway
 Then the payment should be accepted And the magento order status should be ”processing”
17. Scenario: Paying with a credit card
 Given AwesomePay has credit card payments enabled
 When I have credit card 4444333322221111 And the credit card has unlimited funds on payment gateway
 Then the payment should be accepted And the magento order status should be ”processing”
18. Scenario: Paying with a credit card
 Given AwesomePay has credit card payments enabled
 And I have credit card 4444333322221111 And the credit card has unlimited funds on payment gateway When I pay £42 using that credit card
 Then the payment should be accepted And the magento order status should be ”processing”
19. Scenario: Paying with a credit card
 Given the payment gateway has credit card payments enabled
 And I have credit card 4444333322221111 And the credit card has unlimited funds on payment gateway When I pay £42 using that credit card
 Then the payment should be accepted And the magento order status should be ”processing”
20. AwesomePay Magento Interfaces Interfaces Domain
21. Scenario: Paying with a credit card
 Given the payment gateway has credit card payments enabled
 And I have credit card 4444333322221111 And the credit card has unlimited funds on payment gateway When I pay £42 using that credit card
 Then the payment should be accepted And the magento order status should be ”processing”
22. Scenario: Paying with a credit card
 Given the payment gateway has credit card payments enabled
 And I have credit card 4444333322221111 And the credit card has unlimited funds on payment gateway When I pay £42 using that credit card
 Then the payment should be accepted
23. /**
 * @Given the payment gateway has credit card payments enabled
 */
 public function thePaymentGatewayHasCreditCardPaymentsEnabled()
 {
 $this->paymentGateway = new FakePaymentGateway();
 expect( $this->paymentGateway->HasCreditCardPaymentsEnabled() )->toBe(true);
 }
24. /**
 * @Given I have credit card :aCreditCard
 */
 public function iHaveCreditCard(CreditCard $aCreditCard)
 {
 $this->creditCard = $aCreditCard;
 }
25. /**
 * @Transform :aCreditCard
 */
 public function transformNumberToCreditCard($cardNumber)
 {
 return CreditCard::fromNumber($cardNumber);
 }
26. CreditCard::fromNumber($cardNumber); Named Constructor
27. /**
 * @Given the credit card has unlimited funds on payment gateway
 */
 public function theCreditCardHasUnlimitedFundsOnPaymentGateway()
 {
 $this->paymentGateway->cardHasUnlimitedCredit( $this->creditCard );
 }
28. Scenario: Paying with a credit card
 Given the payment gateway has credit card payments enabled
 And I have credit card 4444333322221111 And the credit card has unlimited funds on payment gateway When I pay £42 using that credit card
 Then the payment should be accepted
29. Scenario: Paying with a credit card
 Given the payment gateway has credit card payments enabled
 And I have credit card 4444333322221111
 And the payment gateway has unlimited credit for that card
 When I pay £42 using that credit card
 Then the payment should be accepted
30. /**
 * @Given the payment gateway has unlimited credit for that card
 */
 public function thePaymentGatewayHasUnlimitedCreditForThatCard()
 {
 $this->paymentGateway->hasUnlimitedCreditFor( $this->creditCard );
 }
31. Code closer to the business language
32. Code changes when business changes
33. Emergent design
34. Decoupling
35. AwesomePay Magento Interfaces Interfaces Domain
36. AwesomePay Magento 2 Interfaces Interfaces Domain
37. AwesomePay Magento 2 Interfaces Interfaces Domain
38. AwesomePay Symfony Application Interfaces Interfaces Domain
39. Mitigates communication problems
40. Easier development
41. Docs for free
42. Test for free
43. Easier QA
44. Respond to change
45. Speaking by experience
46. How about e2e tests?
47. default:
 suites:
 domain:
 contexts: [DomainContext]
48. default:
 suites:
 domain:
 contexts: [DomainContext] 
 web:
 contexts: [WebContext]
 filters: { tags: '@web' }
49. default:
 suites:
 domain:
 contexts: [DomainContext] filters: { tags: '~@ui' }
 web:
 contexts: [WebContext]
 filters: { tags: '@web' }
50. default:
 suites:
 domain:
 contexts: [DomainContext] filters: { tags: '~@ui' }
 web:
 contexts: [WebContext]
 filters: { tags: '@web' } mobile:
 contexts: [MobileContext]
 filters: { tags: '@mobile' }
51. default:
 suites:
 domain:
 contexts: [DomainContext] filters: { tags: '~@ui' }
 web:
 contexts: [WebContext]
 filters: { tags: '@web' } mobile:
 contexts: [MobileContext]
 filters: { tags: '@mobile' } integration:
 contexts: [IntegrationContext]
 filters: { tags: '~@ui' }
52. In sum
53. Bounded domain
54. Decoupled parts of our application
55. Decoupling from frameworks
56. Better understanding of the business domain
57. Reduction of communication gaps
58. Easier development
59. Quicker CI builds
60. Easier handover
61. London Magento User Group Thank You!
62. Questions? Related Links http://stakeholderwhisperer.com/posts/2014/10/introducing-modelling-by-example Introducing Modelling by Example Named Constructors in PHP http://verraes.net/2014/06/named-constructors-in-php/ Short Intro to BDD from Konstantin Kudryashov https://www.youtube.com/watch?v=njcHzGYv7nI Social Twitter: @mpmlopes