Page factory pattern in Selenium Python - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the Page Factory pattern in Selenium?

Page Factory is a design pattern in Selenium that helps initialize web elements easily using annotations, making tests cleaner and easier to maintain.

beginner

How do you declare a web element using Page Factory in Python?

You define locators as class attributes using tuples with By, and use the @property decorator to lazily locate and return elements when first accessed.

intermediate

Why is Page Factory pattern preferred over traditional element locating?

Because it reduces code duplication, improves readability, and initializes elements only when they are used, which can improve test performance.

intermediate

What is the role of lazy initialization in Page Factory?

It initializes web elements lazily when accessed so they can be used directly without calling find_element repeatedly each time.

beginner

Give a simple example of a Page Factory class in Selenium Python.

from selenium.webdriver.common.by import By

class LoginPage:
    username_loc = (By.ID, 'username')
    password_loc = (By.ID, 'password')
    login_button_loc = (By.ID, 'login')

    def __init__(self, driver):
        self.driver = driver

    @property
    def username(self):
        return self.driver.find_element(*self.username_loc)

    @property
    def password(self):
        return self.driver.find_element(*self.password_loc)

    @property
    def login_button(self):
        return self.driver.find_element(*self.login_button_loc)

    def login(self, user, pwd):
        self.username.send_keys(user)
        self.password.send_keys(pwd)
        self.login_button.click()

What does the Page Factory pattern help with in Selenium?

A Writing SQL queries

B Managing browser cookies

C Creating database connections

D Initializing web elements efficiently

Page Factory is used to initialize web elements efficiently in Selenium tests.

Which is used to lazily initialize elements in Page Factory (Python)?

A @property

B start_elements

C load_elements

D create_elements

The @property decorator initializes web elements lazily when accessed in the Python Page Factory pattern.

In Page Factory, when are web elements initialized?

A Only when they are used

B At the start of the test suite

C After the test finishes

D Before the browser opens

Page Factory initializes elements lazily, meaning only when they are used.

Which of these is NOT a benefit of using Page Factory?

A Automatic element initialization

B Faster test execution by skipping element checks

C Improved code readability

D Reduced code duplication

Page Factory does not skip element checks; it initializes elements efficiently but does not skip validations.

What is the main purpose of locators in Page Factory?

A To generate reports

B To store test data

C To find web elements on the page

D To manage browser sessions

Locators are used to find web elements on the page for interaction.

Explain the Page Factory pattern and how it improves Selenium test code.

Think about how you find elements in Selenium and how Page Factory changes that.

Describe how you would implement a login page using the Page Factory pattern in Selenium Python.

Imagine the steps a user takes to log in and how to automate them.

Practice

1. What is the main purpose of using the Page Factory pattern in Selenium with Python?

easy

A. To generate test reports automatically

B. To execute tests faster by parallel processing

C. To group web elements in a class for easier access and maintenance

D. To handle browser pop-ups and alerts

Solution

1. Step 1: Understand the role of Page Factory

   Page Factory helps organize web elements by grouping them in a class, making tests easier to read and maintain.

2. Step 2: Compare with other options

   Options B, C, and D describe different Selenium features unrelated to Page Factory's main purpose.

3. Final Answer:

   To group web elements in a class for easier access and maintenance -> Option C

4. Quick Check:

   Page Factory = Group elements for easy access [OK]

Hint: Page Factory groups elements in classes for neat tests [OK]

Common Mistakes:

• Confusing Page Factory with test execution speed
• Thinking it generates reports
• Assuming it handles browser alerts

2. Which of the following is the correct way to declare a web element using Page Factory in Selenium Python?

easy

A. element = driver.find_element(By.ID, 'username')

B. username = (By.ID, 'username')

C. username = self.driver.find_element_by_id('username')

D. username = self.driver.find_element(By.ID, 'username')

Solution

1. Step 1: Identify Page Factory syntax in Python

   Page Factory uses class attributes with locator tuples like (By.ID, 'username') to declare elements before initializing them.

2. Step 2: Check each option

   username = (By.ID, 'username') shows the correct locator tuple usage, which is standard in Page Factory.

3. Final Answer:

   username = (By.ID, 'username') -> Option B

4. Quick Check:

   Page Factory uses locator tuples (By.xx, 'value') [OK]

Hint: Declare Page Factory elements as (By.xx, 'value') tuples [OK]

Common Mistakes:

• Using direct driver.find_element calls instead of Page Factory declarations
• Missing the locator tuple syntax
• Assigning elements directly without initialization

3. Given the following code snippet using Page Factory in Selenium Python, what will be the output of print(page.login_button.is_displayed()) if the button is visible on the page?

from selenium.webdriver.common.by import By
from selenium.webdriver.support.page_factory import PageFactory

class LoginPage:
    def __init__(self, driver):
        self.driver = driver
        PageFactory.init_elements(driver, self)

    login_button = (By.ID, 'loginBtn')

page = LoginPage(driver)
print(page.login_button.is_displayed())

medium

A. True

B. False

C. AttributeError

D. None

Solution

1. Step 1: Understand Page Factory element initialization

   PageFactory.init_elements initializes elements so login_button refers to the actual web element.

2. Step 2: Check the method call

   If the button is visible, is_displayed() returns True, so printing it outputs True.

3. Final Answer:

   True -> Option A

4. Quick Check:

   Visible element's is_displayed() = True [OK]

Hint: is_displayed() returns True if element is visible [OK]

Common Mistakes:

• Expecting None because locator needs initialization
• Confusing AttributeError due to wrong initialization
• Assuming is_displayed() returns string

4. Identify the error in the following Page Factory code snippet and choose the correct fix:

from selenium.webdriver.common.by import By
from selenium.webdriver.support.page_factory import PageFactory

class HomePage:
    def __init__(self, driver):
        self.driver = driver
        PageFactory.init_elements(self, self.driver)

    submit_button = (By.XPATH, "//button[@id='submit']")

page = HomePage(driver)
page.submit_button.click()

medium

A. Initialize elements with PageFactory.init_elements(driver, self)

B. Replace @FindBy with @find_by (lowercase)

C. Import FindBy from correct module and use it as decorator

D. Import and use find_element instead of PageFactory

Solution

1. Step 1: Check PageFactory.init_elements arguments

   The code uses PageFactory.init_elements(self, self.driver) but arguments must be driver first, then self.

2. Step 2: Confirm correct usage

   Using PageFactory.init_elements(driver, self) fixes the error and allows proper element initialization.

3. Final Answer:

   Initialize elements with PageFactory.init_elements(driver, self) -> Option A

4. Quick Check:

   init_elements(driver, self) order [OK]

Hint: PageFactory.init_elements(driver, self) - driver first [OK]

Common Mistakes:

• Wrong argument order for PageFactory.init_elements
• Using wrong decorator name case
• Incorrect PageFactory.init_elements parameters

5. You want to create a Page Factory class for a login page with username, password fields, and a login button. Which approach correctly applies the Page Factory pattern to initialize and use these elements in Selenium Python?

hard

A. Write all element locators inside test functions without any class or decorator

B. Use driver.find_element calls inside each test method without class grouping

C. Create global variables for elements outside any class and access them directly

D. Declare elements with @FindBy decorators, initialize with PageFactory.init_elements, then use element methods

Solution

1. Step 1: Understand Page Factory best practice

   Page Factory groups elements in a class using locator tuples and initializes them with PageFactory.init_elements.

2. Step 2: Compare with other options

   Options B, C, and D do not use Page Factory pattern and lead to less maintainable code.

3. Final Answer:

   Declare elements with @FindBy decorators, initialize with PageFactory.init_elements, then use element methods -> Option D

4. Quick Check:

   Page Factory = locators + init_elements + class grouping [OK]

Hint: Use locators and init_elements to organize page elements [OK]

Common Mistakes:

• Skipping class and locators for elements
• Using driver calls directly in tests
• Not initializing elements with PageFactory