Page factory pattern in Selenium Python

Introduction

The Page Factory pattern helps organize web page elements in tests. It makes tests easier to read and maintain by grouping element locators and actions in one place.

When you want to keep your test code clean and organized.

When you have many web elements to interact with on a page.

When you want to reuse page elements and actions across multiple tests.

When you want to reduce duplicate code for locating elements.

When you want your tests to be easier to update if the web page changes.

Syntax

Selenium Python

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(self.driver, self)
    username = (By.ID, 'username')
    password = (By.ID, 'password')
    login_button = (By.ID, 'loginBtn')

Use By to specify how to find elements (ID, NAME, XPATH, etc.).

Page Factory groups element locators inside a class representing the page.

Examples

This example shows locating elements by their name attribute.

Selenium Python

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.driver, self)
    search_box = (By.NAME, 'q')
    search_button = (By.NAME, 'btnK')

This example uses XPath and CSS selectors to find elements.

Selenium Python

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

class ContactPage:
    def __init__(self, driver):
        self.driver = driver
        PageFactory.init_elements(self.driver, self)
    email_field = (By.XPATH, '//input[@type="email"]')
    submit_button = (By.CSS_SELECTOR, 'button.submit')

Sample Program

This test script opens a login page, uses the Page Factory pattern to find elements, and performs a login action. It prints a confirmation message after trying to log in.

Selenium Python

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

class LoginPage:
    def __init__(self, driver):
        self.driver = driver
        PageFactory.init_elements(self.driver, self)
    username = (By.ID, 'username')
    password = (By.ID, 'password')
    login_button = (By.ID, 'loginBtn')

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

# Setup WebDriver (example with Chrome)
driver = webdriver.Chrome()
driver.get('https://example.com/login')

login_page = LoginPage(driver)
login_page.login('testuser', 'testpass')

# Wait to see the result
time.sleep(2)

print('Login attempted')
driver.quit()

Important Notes

Always initialize elements inside the page class constructor.

Use clear and descriptive names for element variables.

Page Factory helps keep tests clean but does not replace good test design.

Summary

Page Factory groups web elements in a class for easy access.

It makes tests easier to read and maintain.

Use it to reduce duplicate code and improve test organization.

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