Master Selenium Python: Explicit Waits, Scrolling, Zoom, and Advanced Browser Controls

Handling Different Wait Scenarios

In Selenium automation, pages may need time to load or you may want to wait for a specific element before proceeding. The WebDriverWait class enables explicit waits by defining a condition and a timeout; if the condition is not met, a TimeoutException is raised.

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

driver = webdriver.Firefox()
driver.get("https://www.example.com/")
timeout = 10

try:
    element_present = EC.presence_of_element_located((By.LINK_TEXT, 'Sitemap'))
    WebDriverWait(driver, timeout).until(element_present)
except TimeoutException:
    print("User lookup timed out!")

driver.quit()

Scrolling Operations on Web Pages

When testing, you may need to scroll up or down. Using execute_script() with JavaScript commands such as window.scrollTo() achieves the same effect. The example scrolls to the bottom of the page, pauses, then scrolls back to the top.

from selenium import webdriver
from time import sleep

driver = webdriver.Firefox()
driver.get("https://www.example.com/")

# Scroll to page bottom
driver.execute_script("window.scrollTo(0, document.body.scrollHeight);")
sleep(10)

# Scroll to page top
driver.execute_script("window.scroll(0, 0);")
sleep(10)

driver.quit()

Zoom In and Out with Selenium

To zoom or shrink the page, apply the CSS transform property. For Firefox, the MozTransform property is used. The script first scales the page to 200% and then restores it to 100%.

from selenium import webdriver
from time import sleep

driver = webdriver.Firefox()
driver.get("https://www.example.com/")

# Zoom to 200%
driver.execute_script('document.body.style.MozTransform = "scale(2.0)";')
driver.execute_script('document.body.style.MozTransformOrigin = "0 0";')
sleep(10)

# Restore to 100%
driver.execute_script('document.body.style.MozTransform = "scale(1.0)";')
driver.execute_script('document.body.style.MozTransformOrigin = "0 0";')
sleep(10)

driver.quit()

Getting Element Size

Locate an element by its ID and use the .size attribute to obtain its width and height.

from selenium import webdriver
from time import sleep

driver = webdriver.Firefox()
driver.get("http://demos.example.com/test_Menu.html")

search_element = driver.find_element_by_id("createDestroyButton")
print(search_element.size)

driver.quit()

Retrieving Element Coordinates

Similar to size, the .location attribute returns the X and Y coordinates of the element.

from selenium import webdriver
from time import sleep

driver = webdriver.Firefox()
driver.get("http://demos.example.com/test_Menu.html")

search_element = driver.find_element_by_id("createDestroyButton")
print(search_element.location)

driver.quit()

Disabling JavaScript via Custom Profile

To test cross‑browser compatibility without JavaScript, modify the Firefox profile preferences. Set javascript.enabled to False and launch the browser with this profile.

from selenium import webdriver

ff_profile = webdriver.FirefoxProfile()
ff_profile.DEFAULT_PREFERENCES['frozen']['javascript.enabled'] = False
ff_profile.set_preference("app.update.auto", False)
ff_profile.set_preference("app.update.enabled", False)
ff_profile.update_preferences()

driver = webdriver.Firefox(ff_profile)
# Verify the setting
driver.get("about:config")

Setting Manual Proxy Configuration

When a test requires a specific proxy, import the proxy module, set the type to MANUAL, provide the IP address and port, and attach the configuration to the desired capabilities before launching the browser.

from selenium import webdriver
from selenium.webdriver.common.proxy import Proxy, ProxyType

proxy_settings = Proxy()
proxy_settings.proxy_type = ProxyType.MANUAL
proxy_settings.http_proxy = "ip_address:port_number"
proxy_settings.socks_proxy = "ip_address:port_number"
proxy_settings.ssl_proxy = "ip_address:port_number"

capabilities = webdriver.DesiredCapabilities.FIREFOX
proxy_settings.add_to_capabilities(capabilities)

driver = webdriver.Firefox(desired_capabilities=capabilities)