Gherkin for test automation in agile

GherkinAutomate your testing using Gherkin for

BDD

About• This slide deck is about the Gherkin language which

is used to drive test automation.

vireshdoshi@time2test.co.uk 2

Aim• If you are doing Agile then it’s a no brainer to use

Gherkin to drive your automation efforts.

vireshdoshi@time2test.co.uk 3

Background• Created by a clever chap called Dan North in 2009.

vireshdoshi@time2test.co.uk 4

In a nutshellFeature: Log in and out of the site.

In order to maintain an account

As a site visitor

I need to log in and out of the site.

@monsterlogin

Scenario: Logs in to the site

Given I am on "/"

When I follow "Sign In"

And I fill in "EmailAddress" with “jonny.jones@gbmail.com"

And I fill in "Password" with “MyPassword123"

And I press "Sign In"

Then I should see "Welcome Jonny"

And I should see "Jobs You Might Like"

vireshdoshi@time2test.co.uk 5

What is it?• Business readable domain specific language.

• It uses a very simple syntax.

• Tackles the business needs.

• Aims to automate the main business scenarios.

• Outside in design philosophy.

• Software practices – evolved.

• Compliments the Agile/SCRUM process.

• Starting point for test automation.

vireshdoshi@time2test.co.uk 6

What it isn’t?• It’s not a programming language.

• It’s not a unit testing tool.

• It’s got nothing to do with Kebabs

vireshdoshi@time2test.co.uk 7

What is BDD?• It stands for Behavior Driven Development.

• Think TDD – test driven development for

development driven by testing.

• Describe the behaviors and then develop to satisfy

those behaviors.

vireshdoshi@time2test.co.uk 8

BDD vs. Traditional• Test automation team usually trawl through

requirements documents and automate in similar

fashion to how developers develop. This introduces

ambiguity between how test and dev interpret

requirements.

• Usually automation is done after the developers.

• The Gherkin syntax ( acceptance criteria) is the

requirements which are deemed to be signed off

between dev, test and business.

vireshdoshi@time2test.co.uk 9

Benefits• Plain business text.

• Understood by business and developers

• Targets the business requirements.

• Significant proportion of the functional

specifications is written as user stories.

• Small command set to learn.

• Just enough living documentation

vireshdoshi@time2test.co.uk 10

Where to start?• BDD starts with a conversation between

stakeholders.

• Goal is to determine the features and derive the

acceptance criteria.

• Determine the Done.

vireshdoshi@time2test.co.uk 11

Syntax: FeatureFeature – The text acts as the high level information for

the test. Nothing gets processed.

Feature: Log in and out of the site.

In order to maintain an account

As a site visitor

I need to log in and out of the site.

vireshdoshi@time2test.co.uk 12

Syntax: BackgroundBackground – Executed before each scenario.

Background:

Given I am logged in

vireshdoshi@time2test.co.uk 13

Syntax: ScenarioScenario – Main part of the BDD feature file with test

steps.

Scenario: Logs in to the site

Given I am on "/"

When I follow "Sign In"

And I fill in "EmailAddress" with

“jonny.jones@gbmail.com"

And I fill in "Password" with “MyPassword123"

And I press "Sign In"

Then I should see "Welcome Jonny"

And I should see "Jobs You Might Like"

vireshdoshi@time2test.co.uk 14

Syntax: Scenario OutlineScenario Outline – use with examples syntax and executes the scenario multiple times.

@wip

Scenario Outline: Click through all the account pages and assert

present

Given I click on account "editProfile"

Then I should see "Contact Information"

And I follow "<account_link>"

Then I should see "<expected_text>"

Examples:

| account_link | expected_text |

| Photo | Choose a photo for your professional profile. |

| Education | Degree Level |

vireshdoshi@time2test.co.uk 15

Syntax: GivenGiven – a test step that defines the ‘context’

Given I am on "/"

vireshdoshi@time2test.co.uk 16

Syntax: WhenWhen – a test step that defines the ‘action’ performed

When I follow "Sign In"

vireshdoshi@time2test.co.uk 17

Syntax: AndAnd – additional test step that defines the ‘action’

performed

And I fill in "EmailAddress" with

“jonny.jones@gbmail.com"

vireshdoshi@time2test.co.uk 18

Syntax: ThenThen – test step that defines the ‘outcome’

Then I should see "Welcome Jonny"

vireshdoshi@time2test.co.uk 19

Syntax: ButBut – additional test step that defines the ‘action’ or

‘outcome’

But I should see "Welcome Jonny"

vireshdoshi@time2test.co.uk 20

Test steps• Given , When, Then, And , But are test steps

• They can be used interchangeably. The interpreter

doesn’t care what is used however they may not

make ‘sense’ when read!

vireshdoshi@time2test.co.uk 21

TermsUser story – agile term used to describe an end to end

journey of a feature

Cucumber – term used to describe the interpreter

used to process Gherkin syntax

Tear Down – term used in automation to describe the

series of actions executed at the end of scenario

execution.

Setup – term used in automation to describe the series

of actions executed at the beginning of scenario

execution.

vireshdoshi@time2test.co.uk 22

TechnicalLets look at how Gherkin actually works in real life

vireshdoshi@time2test.co.uk 23

Demo• Demo will show the Gherkin files come to life using

Behat and Mink on a PHP using Selenium Webdriver

• The files for this tutorial are stored on GITHUB

• https://github.com/VireshDoshi/behat3-mink-

website

vireshdoshi@time2test.co.uk 24

Behat and Mink• Behat is a PHP tool that interprets.

• Mink is a library that interfaces with Web Browsers.

• Mink Extensions is a library that contains useful

Gherkin steps especially designed for the web.

vireshdoshi@time2test.co.uk 25

Feature file• Out of the box, The following feature file requires minimum coding

Feature: Log in and out of the site.

In order to maintain an account

As a site visitor

I need to log in and out of the site.

@monsterlogin

Scenario: Logs in to the site

Given I am on "/"

When I follow "Sign In"

And I fill in "EmailAddress" with "simon.jones@mailinator.com"

And I fill in "Password" with "12Xxxxxxxxx"

And I press "Sign In"

Then I should see "Welcome Simon"

And I should see "Jobs You Might Like"

vireshdoshi@time2test.co.uk 26

FeatureContext.php• This special Behat file contains the code that connects the Behat feature file to PHP code and Mink • <?php

• use Behat\Behat\Tester\Exception\PendingException;• use Behat\Behat\Context\Context;• use Behat\Behat\Context\SnippetAcceptingContext;• use Behat\Gherkin\Node\PyStringNode;• use Behat\Gherkin\Node\TableNode;• use Behat\MinkExtension\Context\MinkContext;

• /**• * Defines application features from the specific context.• */• class FeatureContext extends MinkContext implements SnippetAcceptingContext• {• /**• * Initializes context.• *• * Every scenario gets its own context instance.• * You can also pass arbitrary arguments to the• * context constructor through behat.yml.• */• public function __construct()• {• }• }

vireshdoshi@time2test.co.uk 27

Behat.yml• This special file contains setup details for Behatdefault:

extensions:

Behat\MinkExtension:

base_url: 'http://www.monster.co.uk'

browser_name: firefox

sessions:

default:

selenium2: ~

suites:

backend:

contexts:

- FeatureContext:

screen_shot_path: ./screenshot

vireshdoshi@time2test.co.uk 28

Custom stepAnd I fill in "EmailAddress" with a unique email simon.jones@mailinator.com

/**

* @Then I fill in :arg1 with a unique email :arg2

*/

public function iFillInWithAUniqueEmail($in_field, $in_email)

{

$session = $this->getSession();

$page=$session->getPage();

$random_num=mt_rand();

$parts= explode('@',$in_email);

$user=$parts[0];

$domain=$parts[1];

$email_element=$page->find('css','#' . $in_field);

$random_email = $user . $random_num . '@' . $domain;

$email_element->setValue($random_email);

echo "generated random email = [" . $random_email . "]\n";

}

vireshdoshi@time2test.co.uk 29

Languages• All these languages are supported :

• PHP, Java, Ruby, Python, C Sharp

vireshdoshi@time2test.co.uk 30

Conclusion• Technically, in 5 simple steps, BDD can be

introduced to your project.

• If you are doing Agile then it’s a no brainer to use

Gherkin to drive your automation efforts.

vireshdoshi@time2test.co.uk 31