Cookie management in Selenium Python - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output of this Selenium cookie retrieval code?

Given the following Selenium Python code snippet, what will be printed?

Selenium Python

from selenium import webdriver
from selenium.webdriver.chrome.service import Service
from selenium.webdriver.chrome.options import Options

options = Options()
options.add_argument('--headless')
service = Service()
driver = webdriver.Chrome(service=service, options=options)
driver.get('https://example.com')
driver.add_cookie({'name': 'testcookie', 'value': '12345'})
cookie = driver.get_cookie('testcookie')
print(cookie['value'])
driver.quit()

A 12345

B None

C KeyError

D selenium.common.exceptions.InvalidCookieDomainException

💡 Hint

Remember that after adding a cookie, you can retrieve it by its name.

The code adds a cookie named 'testcookie' with value '12345' to the current domain and then retrieves it. The print statement outputs the value '12345'.

❓ assertion

intermediate

Which assertion correctly verifies a cookie named 'session' exists?

You want to assert that a cookie named 'session' is present in the browser using Selenium Python. Which assertion is correct?

A assert driver.get_cookie('session')['value'] == ''

B assert 'session' in driver.get_cookies()

C assert driver.get_cookie('session') == {}

D assert driver.get_cookie('session') is not None

💡 Hint

get_cookie returns None if cookie not found.

driver.get_cookie('session') returns None if the cookie does not exist. So checking it is not None confirms presence.

🔧 Debug

advanced

Why does this Selenium code raise an InvalidCookieDomainException?

Consider this code snippet: from selenium import webdriver driver = webdriver.Chrome() driver.add_cookie({'name': 'user', 'value': 'abc'}) driver.get('https://example.com') Why does it raise selenium.common.exceptions.InvalidCookieDomainException?

A Because the driver instance is not initialized properly.

B Because the cookie dictionary is missing the 'domain' key.

C Because add_cookie was called before navigating to any page, so no domain is set.

D Because the cookie value 'abc' is invalid.

💡 Hint

Cookies must be added only after loading a page to set the domain.

Selenium requires the browser to be on a page before adding cookies, so the domain is known. Adding cookies before driver.get() causes this error.

❓ framework

advanced

Which Selenium Python test framework setup correctly clears cookies before each test?

You want to clear all cookies before each test in pytest using Selenium WebDriver. Which setup is correct?

A

import pytest

@pytest.fixture(autouse=True)
def clear_cookies(driver):
    driver.delete_all_cookies()

B

import pytest

def clear_cookies(driver):
    driver.delete_all_cookies()

@pytest.fixture(autouse=True)
def setup():
    clear_cookies()

C

import pytest

@pytest.fixture(scope='session', autouse=True)
def clear_cookies(driver):
    driver.delete_all_cookies()

D

import pytest

@pytest.fixture(autouse=True)
def clear_cookies():
    driver.delete_all_cookies()

💡 Hint

Autouse fixtures run automatically before each test and can accept driver as argument.

Option A defines an autouse fixture that accepts the driver and deletes cookies before each test. Others either miss autouse or driver argument.

🧠 Conceptual

expert

What is the main reason to manage cookies explicitly in Selenium tests?

Why do testers often add, delete, or modify cookies explicitly in Selenium automated tests?

A To speed up page loading by caching cookies locally.

B To simulate user sessions and test authentication flows without manual login.

C To bypass browser security restrictions on cross-site scripting.

D To automatically generate test reports based on cookie data.

💡 Hint

Think about how cookies relate to user login and session state.

Managing cookies allows tests to simulate logged-in users by setting session cookies directly, avoiding repetitive manual login steps.