Running tests on Grid in Selenium Python - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a remote WebDriver session connecting to the Selenium Grid hub.

Selenium Python

from selenium import webdriver
from selenium.webdriver.common.desired_capabilities import DesiredCapabilities

driver = webdriver.Remote(command_executor='[1]', desired_capabilities=DesiredCapabilities.CHROME)
driver.get('https://example.com')
driver.quit()

Drag options to blanks, or click blank then click option'

Ahttp://localhost:4444/wd/hub

Bhttp://127.0.0.1:5555/wd/hub

Chttp://localhost:8080/wd/hub

Dhttp://192.168.1.1:4444

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong port number

Omitting '/wd/hub' in the URL

Using localhost but wrong port

The Selenium Grid hub URL usually runs on port 4444 with the path '/wd/hub'. This URL tells the Remote WebDriver where to send commands.

2fill in blank

medium

Complete the code to specify the browser as Firefox when creating a remote WebDriver.

Selenium Python

from selenium import webdriver
from selenium.webdriver.common.desired_capabilities import DesiredCapabilities

caps = DesiredCapabilities.[1]
driver = webdriver.Remote(command_executor='http://localhost:4444/wd/hub', desired_capabilities=caps)
driver.get('https://example.com')
driver.quit()

Drag options to blanks, or click blank then click option'

AFIREFOX

BSAFARI

CEDGE

DCHROME

Attempts:

3 left

💡 Hint

Common Mistakes

Using lowercase 'firefox'

Using CHROME capability instead

Misspelling the capability name

To run tests on Firefox browser via Selenium Grid, use DesiredCapabilities.FIREFOX.

3fill in blank

hard

Fix the error in the code to correctly set the desired capabilities for running tests on Edge browser.

Selenium Python

from selenium import webdriver
from selenium.webdriver.common.desired_capabilities import DesiredCapabilities

caps = DesiredCapabilities.[1]
driver = webdriver.Remote(command_executor='http://localhost:4444/wd/hub', desired_capabilities=caps)
driver.get('https://example.com')
driver.quit()

Drag options to blanks, or click blank then click option'

AEDGE_CHROMIUM

BCHROME

CEDGE

DFIREFOX

Attempts:

3 left

💡 Hint

Common Mistakes

Using CHROME capability for Edge

Using non-existent capability 'EDGE_CHROMIUM'

Misspelling 'EDGE'

For Edge browser, the correct desired capability is DesiredCapabilities.EDGE.

4fill in blank

hard

Fill both blanks to create a remote WebDriver that connects to the Grid hub and uses Chrome browser capabilities.

Selenium Python

from selenium import webdriver
from selenium.webdriver.common.desired_capabilities import DesiredCapabilities

hub_url = '[1]'
caps = DesiredCapabilities.[2]
driver = webdriver.Remote(command_executor=hub_url, desired_capabilities=caps)
driver.get('https://example.com')
driver.quit()

Drag options to blanks, or click blank then click option'

Ahttp://localhost:4444/wd/hub

Bhttp://localhost:5555/wd/hub

CCHROME

DFIREFOX

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong port in hub URL

Using Firefox capability instead of Chrome

Omitting '/wd/hub' in URL

The hub URL is usually 'http://localhost:4444/wd/hub' and the Chrome browser capability is 'CHROME'.

5fill in blank

hard

Fill all three blanks to create a remote WebDriver session with Firefox browser, connecting to the Grid hub, and then navigate to a URL.

Selenium Python

from selenium import webdriver
from selenium.webdriver.common.desired_capabilities import DesiredCapabilities

hub = '[1]'
caps = DesiredCapabilities.[2]
driver = webdriver.Remote(command_executor=hub, desired_capabilities=caps)
driver.get('[3]')
driver.quit()

Drag options to blanks, or click blank then click option'

Ahttp://localhost:4444/wd/hub

BFIREFOX

Chttps://example.com

DCHROME

Attempts:

3 left

💡 Hint

Common Mistakes

Using Chrome capability instead of Firefox

Missing '/wd/hub' in hub URL

Using incorrect URL format

The hub URL is 'http://localhost:4444/wd/hub', the browser capability for Firefox is 'FIREFOX', and the URL to open is 'https://example.com'.

Practice

1. What is the main purpose of using Selenium Grid when running tests?

easy

A. To run tests on multiple browsers and machines remotely

B. To write test scripts faster

C. To debug tests locally

D. To create test reports automatically

Solution

1. Step 1: Understand Selenium Grid's role

   Selenium Grid allows running tests on different browsers and machines remotely, enabling parallel testing.

2. Step 2: Compare options with Grid's purpose

   Options A, B, and D describe other testing activities but not the main purpose of Selenium Grid.

3. Final Answer:

   To run tests on multiple browsers and machines remotely -> Option A

4. Quick Check:

   Grid purpose = remote multi-browser testing [OK]

Hint: Grid runs tests remotely on many browsers at once [OK]

Common Mistakes:

• Confusing Grid with test script writing tools
• Thinking Grid is for debugging locally
• Assuming Grid creates reports automatically

2. Which of the following is the correct way to create a Remote WebDriver session in Python for Selenium Grid?

easy

A. driver = webdriver.Grid('http://hub:4444')

B. driver = webdriver.Chrome()

C. driver = webdriver.Remote('chrome')

D. driver = webdriver.Remote(command_executor='http://hub:4444/wd/hub', desired_capabilities={'browserName': 'chrome'})

Solution

1. Step 1: Review Remote WebDriver syntax

   Creating a Remote WebDriver requires specifying the Grid Hub URL and desired capabilities as a dictionary.

2. Step 2: Check each option's correctness

   driver = webdriver.Remote(command_executor='http://hub:4444/wd/hub', desired_capabilities={'browserName': 'chrome'}) correctly uses webdriver.Remote with command_executor URL and capabilities. Options A, B, and C are incorrect or invalid syntax.

3. Final Answer:

   driver = webdriver.Remote(command_executor='http://hub:4444/wd/hub', desired_capabilities={'browserName': 'chrome'}) -> Option D

4. Quick Check:

   Remote WebDriver needs hub URL and capabilities [OK]

Hint: Use webdriver.Remote with hub URL and browser capabilities [OK]

Common Mistakes:

• Using webdriver.Chrome() instead of Remote
• Passing browser name directly without capabilities dict
• Using non-existent webdriver.Grid class

3. What will be the output when running this code snippet connected to a Selenium Grid Hub?

from selenium import webdriver
caps = {'browserName': 'firefox'}
driver = webdriver.Remote(command_executor='http://localhost:4444/wd/hub', desired_capabilities=caps)
driver.get('https://example.com')
print(driver.title)
driver.quit()

medium

A. Raises a SyntaxError due to caps dictionary

B. Prints the title of https://example.com and closes the browser

C. Fails to connect because 'firefox' is invalid browserName

D. Prints None and leaves browser open

Solution

1. Step 1: Analyze code behavior with Selenium Grid

   The code creates a Remote WebDriver session for Firefox on the Grid Hub, opens example.com, prints the page title, then quits.

2. Step 2: Validate expected output and errors

   No syntax errors exist. 'firefox' is a valid browserName. The title prints correctly, and driver.quit() closes the session.

3. Final Answer:

   Prints the title of https://example.com and closes the browser -> Option B

4. Quick Check:

   Remote driver opens page, prints title, quits [OK]

Hint: Remote driver prints page title then quits cleanly [OK]

Common Mistakes:

• Thinking caps dictionary causes syntax error
• Assuming 'firefox' is invalid browserName
• Forgetting driver.quit() closes session

4. You wrote this code to run tests on Selenium Grid but get a connection error:

driver = webdriver.Remote(command_executor='http://localhost:5555/wd/hub', desired_capabilities={'browserName': 'chrome'})

What is the most likely cause?

medium

A. The Grid Hub is not running on port 5555

B. The browserName 'chrome' is invalid

C. webdriver.Remote cannot be used with command_executor

D. Missing import statement for webdriver

Solution

1. Step 1: Check connection details in command_executor

   The URL uses port 5555, but Selenium Grid Hub usually runs on port 4444 by default.

2. Step 2: Identify common connection error causes

   If the Hub is not running on port 5555, connection fails. Browser name 'chrome' is valid, webdriver.Remote supports command_executor, and imports are assumed correct.

3. Final Answer:

   The Grid Hub is not running on port 5555 -> Option A

4. Quick Check:

   Wrong Hub port causes connection error [OK]

Hint: Check Hub URL and port carefully for connection errors [OK]

Common Mistakes:

• Assuming browserName 'chrome' is invalid
• Thinking webdriver.Remote disallows command_executor
• Ignoring Hub must be running before connecting

5. You want to run tests on Selenium Grid for Chrome and Firefox browsers simultaneously. Which approach correctly sets this up in Python?

hard

A. Use webdriver.Chrome() and webdriver.Firefox() locally without Remote

B. Set desired_capabilities to {'browserName': 'chrome,firefox'} in one Remote call

C. Create two Remote WebDriver instances with different desired_capabilities and run tests in parallel threads

D. Run tests sequentially on one Remote WebDriver instance switching browsers

Solution

1. Step 1: Understand parallel testing on Selenium Grid

   To test multiple browsers simultaneously, create separate Remote WebDriver instances with specific capabilities for each browser.

2. Step 2: Evaluate options for correctness

   Create two Remote WebDriver instances with different desired_capabilities and run tests in parallel threads correctly describes creating two instances and running them in parallel threads. Use webdriver.Chrome() and webdriver.Firefox() locally without Remote runs locally, not on Grid. Set desired_capabilities to {'browserName': 'chrome,firefox'} in one Remote call incorrectly tries to combine browsers in one call. Run tests sequentially on one Remote WebDriver instance switching browsers runs sequentially, not simultaneously.

3. Final Answer:

   Create two Remote WebDriver instances with different desired_capabilities and run tests in parallel threads -> Option C

4. Quick Check:

   Parallel tests need separate Remote drivers per browser [OK]

Hint: Use separate Remote drivers and threads for parallel browsers [OK]

Common Mistakes:

• Trying to specify multiple browsers in one desired_capabilities dict
• Running tests locally instead of on Grid
• Running tests sequentially instead of parallel