This document discusses using Behat and Gherkin to write Behavior Driven Development (BDD) tests for APIs. It covers how to set up Behat, write tests in the Gherkin language format, and have those tests execute PHP code. The agenda includes explaining Behat and Gherkin, providing code examples, writing tests, grouping tests, and reviewing test results. Live coding demonstrations are given of writing BDD tests for sample APIs and running them with Behat to validate behaviors.

1. BDD API Tests with
Gherkin and Behat
Mark Niebergall

2. https://i.pinimg.com/originals/81/c6/a2/81c6a285adb6c984f14329516f4eca13.gif

3. https://pbs.twimg.com/media/EI7j7OIWkAA-hsY.png

4. Objective
• How to use Behat framework
• How to write tests in Gherkin
• Understand benefits of BDD
• BDD API development
- Live code BDD tests and APIs

5. Setup
• PHP 7 installed
• git clone https://github.com/mbniebergall/bdd.git
• composer install
• Run PHP locally
- php -S 0.0.0.0:8088 -t bdd/public/

6. Agenda
• 1:00-1:30 Behat and Gherkin
• 1:30-2:00 Code Examples
• 2:00-2:25 Writing Tests
• 2:25-2:35 Break
• 2:35-3:00 Writing Tests
• 3:00-3:30 Group Tests
• 3:30-4:00 Test Results, Recap

7. Behat and Gherkin

8. Behat and Gherkin
• TDD
• API
• BDD
• Behat
• Gherkin
• TDD and BDD

9. TDD
• Write a test - Fail
• Write some code - Pass
• Repeat

10. TDD
• Test Drive Development
- PHPUnit
- Target application logic

11. API
• Expose functionality to requests

12. API
• Application Programming Interface
• Inbound requests
• Outbound response
• Frameworks for that
- Slim
- Zend/Laminas
- Laravel
- Others

13. API
• Middleware!

14. BDD
• Behavioral Driven Development
• Test code behaviors
• Test API behaviors

15. https://i.pinimg.com/originals/69/eb/29/69eb293ffb2d1166cbaed9be4dd3d348.gif

16. BDD
• Write a test - Fail
• Write some code - Pass
• Repeat

17. Behat
• BDD testing framework
• Tests written in Gherkin
• Translate to associated PHP code

18. Behat
• composer development-enable
composer require --dev behat/behat
composer require --dev fzaninotto/faker
composer require --dev guzzlehttp/guzzle
[optional]
composer require illuminate/support
composer require zfcampus/zf-api-problem
vendor/bin/behat --init
vendor/bin/behat features/some_api.feature
vendor/bin/behat --tags=@test features/some/other_code.feature
vendor/bin/behat -s QA features/great_tests.feature

19. Behat
• /features/ with some_test.feature files
- Written in Gherkin
• /features/bootstrap/ with FeatureContext.php
- PHP that Gherkin maps to

20. Gherkin
• Human readable
• Describes use cases

21. Gherkin
• Feature: Use case description
- Scenario: What is expected behavior
‣ Given …
And …
When …
Then …
And …

22. Gherkin
• Feature: Use case description
- Scenario: What is expected behavior
‣ Given …
And …
When …
Then …
And …
# optionally more tests
Given …
…

23. Gherkin
• Translates to functions written in a programming language
- Given Something is in a state
When I request “GET /api/some/path/123”
Then I should get a “200” response
And The field “someData” should be “some value”

24. Gherkin
• Given Something is in a state “Pending”
• /**
* @Given Something is in a state :state
*/
• /**
* @Given /^Something is in a state “([^”]*)”$/
*/
• public function somethingIsInAState(string $state)
{
$this->state = $state;
}

25. Gherkin
Feature:
As a welcoming person
I want to say hello to someone by name
So that they feel welcomed
@test
Scenario: Simple Test
Given I request "GET /api/helloworld/SunshinePHP”
Then I should get a "200" response
/**
* @Then I should get a :httpStatusCode response
*/
public function iShouldGetAResponse(string $httpStatusCode)
{
$code = $this->response->getStatusCode();
Assert::assertEquals(
$httpStatusCode,
$code,
"Unexpected response code: $codenn" . $this->getResponse()
);
}

26. Gherkin
@failure
Scenario: I should get an error with too short of a name
Given I request "GET /api/helloworld/H"
Then I should get a 422 response
And The "title" field should be "Unprocessable Entity"

27. Gherkin
Scenario: I should say Hello to anyone's name
Given I store a fake "firstName" in the variable %firstName%
When I request "GET /api/helloworld/%firstName%"
Then I should get a 200 response
And The "greeting" field should be "Hello %firstName%”
/**
* @Given /^I store a fake "(.*)" in the variable %(.*)%$/
*/
public function iStoreAFakeValueInTheVariable($fakeName, $variable)
{
$this->storedValues[$variable] = [
'search' => $variable,
'replace' => $this->faker->$fakeName,
];
}

28. TDD and BDD

29. TDD and BDD
• Co-exist
• Both working together
• Testing different things

30. TDD and BDD
• Unit tests are much faster
• Unit tests are more granular
• Behavioral tests are focused on APIs
• Behavioral tests run the code without mocks

31. TDD and BDD
• Behat uses assertion tools (PHPUnit)

32. Time to Code

33. Time to Code
• Review a HelloWorld API
• Choose a new API
• Write Gherkin to describe API
• Run tests - fail
• Write PHP API code
• Run tests - pass

34. Time to Code
• Adding Machine
• Password strength
• Alphabetize
• Randomizer
• Time
• Triangle Solver
• Farenheit to Celcius
• Race pace calculator

35. Break

36. https://i.redd.it/uomspd8crlc41.jpg

37. Time to Code
• Review Previous API
• Choose a new API
• Write Gherkin to describe API
• Run tests - fail
• Write PHP API code
• Run tests - pass

38. Time to Code
• Adding Machine
• Password strength
• Alphabetize
• Randomizer
• Time
• Triangle Solver
• Farenheit to Celcius
• Race pace calculator

39. Group Coding Activity
• Create an API
- Use bdd repo
- New API
- Gherkin tests
- PHP for API
- Push changes up, create a PR

40. Group Coding Activity
• Show and Tell

41. Review
• Concepts
• Benefits
• Cons
• Continuous Integration
• Authentication
• Environments
• Test data

42. Review
• Discussion
• Anything PHP related

43. Review
• Questions?
• https://joind.in/talk/dd8d3

44. Mark Niebergall
• PHP since 2005
• Masters degree in MIS
• Senior Software Engineer
• Drug screening project
• Utah PHP Co-Organizer
• CSSLP, SSCP Certified and SME
• Father, long distance running, fishing, skiing