Automate login functionality using Page Object Model

Preconditions (2)

Step 1: Open the login page URL

Step 2: Enter 'testuser@example.com' in the email input field

Step 3: Enter 'Password123' in the password input field

Step 4: Click the login button

Step 5: Verify that the user is redirected to the dashboard page

Step 6: Verify that the dashboard page contains a welcome message

✅ Expected Result: User successfully logs in and sees the dashboard page with a welcome message

Automation Requirements - Selenium with Python

Assertions Needed:

Verify current URL is dashboard URL after login

Verify presence of welcome message element on dashboard

Best Practices:

Use Page Object Model to separate page locators and actions

Use explicit waits to wait for elements before interacting

Keep test logic separate from page object classes

Automated Solution

Testing Fundamentals

from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC

class LoginPage:
    def __init__(self, driver):
        self.driver = driver
        self.email_input = (By.ID, 'email')
        self.password_input = (By.ID, 'password')
        self.login_button = (By.ID, 'loginBtn')

    def open(self, url):
        self.driver.get(url)

    def enter_email(self, email):
        WebDriverWait(self.driver, 10).until(
            EC.visibility_of_element_located(self.email_input)
        ).send_keys(email)

    def enter_password(self, password):
        WebDriverWait(self.driver, 10).until(
            EC.visibility_of_element_located(self.password_input)
        ).send_keys(password)

    def click_login(self):
        WebDriverWait(self.driver, 10).until(
            EC.element_to_be_clickable(self.login_button)
        ).click()

class DashboardPage:
    def __init__(self, driver):
        self.driver = driver
        self.welcome_message = (By.ID, 'welcomeMsg')

    def is_welcome_message_displayed(self):
        return WebDriverWait(self.driver, 10).until(
            EC.visibility_of_element_located(self.welcome_message)
        ) is not None


def test_login():
    driver = webdriver.Chrome()
    login_page = LoginPage(driver)
    dashboard_page = DashboardPage(driver)

    try:
        login_page.open('https://example.com/login')
        login_page.enter_email('testuser@example.com')
        login_page.enter_password('Password123')
        login_page.click_login()

        WebDriverWait(driver, 10).until(
            EC.url_contains('/dashboard')
        )

        assert '/dashboard' in driver.current_url, 'URL after login is incorrect'
        assert dashboard_page.is_welcome_message_displayed(), 'Welcome message not found on dashboard'

    finally:
        driver.quit()

if __name__ == '__main__':
    test_login()

This code uses the Page Object Model to organize the test.

The LoginPage class holds locators and actions for the login page. It has methods to open the page, enter email, enter password, and click login. Each method waits explicitly for the element to be ready before interacting.

The DashboardPage class holds the locator and method to check if the welcome message is visible on the dashboard.

The test_login function creates a browser driver, uses the page objects to perform the login steps, waits for the dashboard URL, and asserts the URL and welcome message presence.

Explicit waits ensure the test does not fail due to slow loading. Separating page details from test logic makes the code easier to maintain and read.

Common Mistakes - 3 Pitfalls

Putting locators and test steps directly in the test function

Using fixed sleep delays instead of explicit waits

Not verifying the page URL after login

Bonus Challenge

Now add data-driven testing with 3 different sets of login credentials (valid and invalid).

Show Hint