SCREENPLAY
A Journey Beyond The PageObject Pattern
Antony Marcano
Jan Molak
Kostas Mamalis

CONTACT
•
Kostas Mamalis
@agiletestinguk
kostas@masterthought.net
•
Antony Marcano
@AntonyMarcano
antony@riverglide.com
•
Jan Molak
@JanMolak
jan.molak@smartcodeltd.co.uk

CONTEXT

IN THE BEGINNING
•
Long established financial institution
•
Used Scrum with 2 week Sprints
•
Outsourced development to large consultancy
•
No automated acceptance tests (few unit tests)

ALONG THE JOURNEY
•
Realised that automated tests were essential
•
Wrote lots of Cucumber tests
•
Backed by Selenium/WebDriver
•
Used the PageObject Pattern

SELENIUM
AND
THE PAGE OBJECT PATTERN
Illustrated with the Pet Clinic

TESTING THE PET CLINIC

WEBDRIVER EXAMPLE
DesiredCapabilities capabilities = new DesiredCapabilities();
WebDriver driver = new PhantomJSDriver(desiredCapabilities());
driver.get(baseUrl+"owners/find.html");
driver.findElement(By.cssSelector("#search-owner-form button")).click();
assertThat(
driver.findElements(By.cssSelector("owners tbody tr")).size(),
is(10)
);

FINDING ALL OWNERS - WEBDRIVER EXAMPLE
DesiredCapabilities capabilities = new DesiredCapabilities();
WebDriver driver = new PhantomJSDriver(desiredCapabilities());
driver.get(baseUrl+"owners/find.html");
driver.findElement(By.cssSelector("#search-owner-form button")).click();
assertThat(
driver.findElements(By.cssSelector("owners tbody tr")).size(),
is(10)
);

FINDING ALL OWNERS - PAGEOBJECT EXAMPLE
DesiredCapabilities capabilities = new DesiredCapabilities();
WebDriver driver = new PhantomJSDriver(desiredCapabilities());
driver.get(baseUrl+"owners/find.html");
FindOwnersPage findOwners =
PageFactory.initElements(driver, FindOwnersPage.class);
OwnersPage owners = findOwners.findWith(EMPTY_SEARCH_TERMS);
assertThat(owners.numberOfOwners(), is(10));

PROBLEMS AROSE
•
Large PageObject classes
•
Brittle test-code (less than raw Selenium)
•
Duplication across PageObjects for each of the
‘portals’

THEY TRIED THE FOLLOWING
•
Separate behaviour into Navigation Classes
•
Reduce duplication with inheritance
Causing ...
•
Large Navigation classes
•
Deep inheritance hierarchy

EFFECTS ON THE TEAM
•
Took longer and longer to add new tests
•
Got harder to diagnose problems
•
Low trust in the ‘test framework’ and Cucumber
•
Reduced faith
in automated testing
•
Impacted morale

WHAT WAS THE ANSWER?

Antony Marcano at first AAFTT in 2007

THE INSIGHT
Roles
← Who
➥ Goals
← Why
➥ Tasks
← What
➥ Actions ← How
Inspired by Kevin Lawrence’s talk at the first AAFTT in 2007
More of his thinking here: http://www.developertesting.com/archives/month200710/20071013-In%20Praise%20of
%20Abstraction.html

2008 - JNARRATE
@Test
public void should_be_able_to_edit_a_page() {
Given.thatThe(wiki).wasAbleTo(beAtThe(PointWhereItHasBeen.JUST_INSTALLED));
And.thatThe(user).wasAbleTo(navigateToTheHomePage());
And.thatThe(user).wasAbleTo(navigateToTheHomePage());
When.the(user).attemptsTo(
tas
k
changeTheContent().to("Welcome to Acceptance Test Driven Development")
tas
k
);
Then.the(textOnTheScreen().ofThe(user)).
tas
k
shouldBe("Welcome to Acceptance Test Driven Development");
}
Playing with fluent APIs and started to explore the model of Tasks & Actions
(although back then the labels I used more like Kevin’s labels).

2009 - SCREENPLAY - A TASK
public void perform() {
you.need(To.doTheFollowing( // actions
Click.onThe(OptionsMenu.EDIT_BUTTON),
ClearTheContent.ofThe(Editor.CONTENT_PANEL),
Type.theText(newContent).
intoThe(Editor.CONTENT_PANEL),
Click.onThe(Editor.SAVE_BUTTON)
));
}

2012 - THE JOURNEY PATTERN
Actor
performs
Tasks
has
Abilities
composed of
enable
Actions
interact with
Screen
contains
Elements

JOURNEY PATTERN APPLIED
JUNIT
Roles
➥ Goals
➥ Tasks
← Who
← Why
← What
➥ Actions ← How
Actor theReceptionist =
new Actor().with(WebBrowsing.ability());
@Test public void
should_find_all_owners_by_default
theReceptionist.attemptsTo(
Go.to(findOwnersScreen.url()),
Search.forOwnersWith(EMPTY_SEARCH_TERMS),
Count.theNumberOfOwners()
);
Enter.the(searchTerms).
into(findOwnersScreen.searchTerms),
Click.onThe(findOwnersScreen.searchButton)

JOURNEY PATTERN APPLIED
CUCUMBER
Roles
← Who
As a Pet Clinic Receptionist
➥ Goals
← Why
Scenario: Find all owners by default
← What
When I search for owners with BLANK search terms
@When
(“^I search for owners with BLANK search terms$”)
➥ Tasks
theReceptionist.attemptsTo(
Search.forOwnersWith(EMPTY_SEARCH_TERMS)
);
➥ Actions ← How
Enter.the(searchTerms).
into(findOwnersScreen.searchTerms),

PUTTING IT ALL TOGETHER
Actor theReceptionist = new Actor().with(WebBrowsing.ability());
theReceptionist.attemptsTo(
Go.to(findOwnersScreen.url()),
Search.forOwnersWith(EMPTY_SEARCH_TERMS),
Count.theNumberOfOwners()
);
assertThat(
theReceptionist.sawThatThe(numberOfOwners()),
was(theExpectedNumberOfOwners)
);

A TASK
…
private static String searchTerms;
@Override
public void performAs(Actor asAReceptionist) {
asAReceptionist.attemptTo(
Enter.the(searchTerms).into(findOwnersScreen.searchTerms),
Click.onThe(findOwnersScreen.searchButton)
);
}
public SearchForOwnersWith(String searchTerms) {
this.searchTerms = searchTerms;
}
…

A SCREEN
@Url("owners/find.html")
public class FindOwnersScreen extends WebScreen {
@LocateBy(css="#search-owner-form input")
public ScreenElement searchTerms;
@LocateBy(css="#search-owner-form button")
public ScreenElement searchButton;
}

AN ACTION
public class Enter extends WebDriverInteraction implements Perform {
private String text;
private ScreenElement field;
public void performAs(Actor actor) {
web(actor).findElement(field.locator()).sendKeys(text);
}
public Enter(String text) { this.text = text; }
public static Enter the(String text) {return new Enter(text);}
public Perform into(ScreenElement field) {
this.field = field;
return this;
}
}

PROBLEMS SOLVED
•
Smaller “Screen” classes
•
Small, focused “Task” classes
•
Readable code
•
Consistent metaphor
•
Minimal inheritance
•
Removed need for duplication across behaviours previously in
PageObjects or “Navigation” classes

DESIGN PRINCIPLES
•
DRY - navigational steps in one place
•
Separation of Concerns - Page Structure and Actions separate
•
Small Classes - easy to comprehend
•
Single Responsibility - classes focused on one thing
and one thing only
•
Minimise conditional logic - navigational if-thens replaced
with composable sequences

SCREENPLAY REVIVED
Under development for everyone to use
Watch This Space!

CONTACT
•
Kostas Mamalis
@agiletestinguk
kostas@masterthought.net
•
Antony Marcano
@AntonyMarcano
antony@riverglide.com
•
Jan Molak
@JanMolak
jan.molak@smartcodeltd.co.uk

THANK YOU!