Automate login functionality using Page Object pattern

Preconditions (2)

Step 1: Open the login page URL in a browser

Step 2: Enter 'user@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

✅ Expected Result: User successfully logs in and dashboard page is displayed

Automation Requirements - pytest with Selenium WebDriver

Assertions Needed:

Verify current URL is dashboard URL after login

Verify login button is clickable before clicking

Verify email and password fields accept input

Best Practices:

Use Page Object Model to separate page interactions from test logic

Use explicit waits to wait for elements to be ready

Use clear and descriptive assertion messages

Automated Solution

PyTest

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
import pytest

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 load(self, url):
        self.driver.get(url)

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

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

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

@pytest.fixture
def driver():
    driver = webdriver.Chrome()
    yield driver
    driver.quit()


def test_login_success(driver):
    login_page = LoginPage(driver)
    login_page.load("https://example.com/login")
    login_page.enter_email("user@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, "User should be redirected to dashboard after login"

This test uses the Page Object Model (POM) pattern to improve test quality by separating page details from test logic. The LoginPage class encapsulates all interactions with the login page elements. This makes the test test_login_success easier to read and maintain.

Explicit waits ensure elements are ready before interacting, avoiding flaky tests. Assertions check that the user is redirected to the dashboard URL after login, confirming success.

Using pytest fixtures for the WebDriver setup and teardown keeps the test clean and reusable.

Common Mistakes - 3 Pitfalls

Hardcoding element locators inside the test function

Using implicit waits or no waits at all

Not verifying that elements are interactable before clicking

Bonus Challenge

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

Show Hint