Screenshot on failure in Selenium Python - Framework Patterns

Framework Mode - Screenshot on failure

Folder Structure

selenium_project/
├── tests/
│   ├── test_login.py
│   └── test_checkout.py
├── pages/
│   ├── login_page.py
│   └── checkout_page.py
├── utils/
│   ├── screenshot_helper.py
│   └── driver_factory.py
├── config/
│   └── config.yaml
├── reports/
│   └── screenshots/
└── conftest.py
    

Test Framework Layers

• Driver Layer: Manages browser setup and teardown (e.g., driver_factory.py).
• Page Objects: Encapsulate page elements and actions (e.g., login_page.py).
• Tests: Actual test cases using pytest (e.g., test_login.py).
• Utilities: Helpers like screenshot capture on failure (screenshot_helper.py).
• Config: Environment and browser settings (config.yaml).
• Reports: Stores test reports and screenshots (reports/screenshots/).

Configuration Patterns

Use a config.yaml file to store environment URLs, browser choices, and credentials. Load this config in conftest.py to provide fixtures for tests.

Example config.yaml snippet:

environment:
  url: "https://example.com"
browser: "chrome"
credentials:
  username: "testuser"
  password: "password123"
    

Use pytest hooks in conftest.py to capture screenshots on test failure automatically.

Test Reporting and CI/CD Integration

• Use pytest's built-in reporting with --html=report.html for readable reports.
• Store screenshots in reports/screenshots/ with timestamped filenames.
• Integrate with CI tools like GitHub Actions or Jenkins to run tests on push.
• Configure CI to archive reports and screenshots as build artifacts for easy access.

Best Practices

1. Centralize Screenshot Logic: Keep screenshot capture in a utility function to reuse and maintain easily.
2. Use Pytest Hooks: Implement pytest_runtest_makereport to detect failures and trigger screenshots automatically.
3. Organize Screenshots: Save screenshots with clear names and timestamps in a dedicated folder.
4. Keep Tests Clean: Avoid screenshot code inside test cases; use hooks or fixtures instead.
5. Integrate with Reports: Link screenshots in test reports for quick debugging.

Self Check

Where in this folder structure would you add the code that captures a screenshot when a test fails?

Key Result

Use pytest hooks and a utility function to capture and save screenshots automatically on test failure.

Practice

1. What is the main purpose of taking a screenshot on test failure in Selenium?

easy

A. To capture the current state of the web page for debugging

B. To speed up the test execution

C. To improve the browser's performance

D. To automatically fix the test errors

Solution

1. Step 1: Understand the role of screenshots in testing

   Screenshots help testers see what the user saw when the test failed.

2. Step 2: Identify the purpose of capturing screenshots on failure

   They provide visual evidence to debug UI problems quickly.

3. Final Answer:

   To capture the current state of the web page for debugging -> Option A

4. Quick Check:

   Screenshot on failure = capture page state [OK]

Hint: Screenshots show what failed looks like visually [OK]

Common Mistakes:

• Thinking screenshots speed up tests
• Believing screenshots fix errors automatically
• Confusing screenshots with performance tools

2. Which of the following is the correct syntax to take a screenshot in Selenium Python when a test fails?

easy

A. driver.save_screenshot('error.png')

B. driver.takeScreenshot('error.png')

C. driver.capture('error.png')

D. driver.screenshotSave('error.png')

Solution

1. Step 1: Recall Selenium Python screenshot method

   The correct method to save a screenshot is save_screenshot().

2. Step 2: Verify method names and syntax

   Only driver.save_screenshot('error.png') matches Selenium's API.

3. Final Answer:

   driver.save_screenshot('error.png') -> Option A

4. Quick Check:

   Correct method name = save_screenshot [OK]

Hint: Remember method is save_screenshot with underscore [OK]

Common Mistakes:

• Using camelCase instead of snake_case
• Using non-existent methods like capture or screenshotSave
• Missing parentheses or quotes

3. What will be the output if the following Selenium Python code runs and the element is not found?

try:
    driver.find_element(By.ID, 'submit').click()
except Exception as e:
    driver.save_screenshot('fail.png')
    print('Screenshot saved on failure')

medium

A. No output, test passes silently

B. RuntimeError without screenshot

C. SyntaxError due to missing import

D. Screenshot saved on failure

Solution

1. Step 1: Analyze try-except behavior on element not found

   If element is missing, exception triggers except block.

2. Step 2: Check actions in except block

   Screenshot is saved and message printed: 'Screenshot saved on failure'.

3. Final Answer:

   Screenshot saved on failure -> Option D

4. Quick Check:

   Exception triggers screenshot and print [OK]

Hint: Exception triggers except block actions [OK]

Common Mistakes:

• Assuming test passes silently on failure
• Confusing syntax errors with runtime exceptions
• Ignoring the print statement inside except

4. Identify the error in this Selenium Python snippet intended to save a screenshot on failure:

try:
    driver.find_element(By.NAME, 'login').click()
except:
    driver.save_screenshot(failure.png)

medium

A. No error, code is correct

B. Incorrect exception handling syntax

C. Missing quotes around filename in save_screenshot

D. Wrong method name saveScreenshot instead of save_screenshot

Solution

1. Step 1: Check save_screenshot argument syntax

   Filename must be a string in quotes, but here it is unquoted.

2. Step 2: Confirm exception handling and method name

   Except syntax and method name are correct; only filename is wrong.

3. Final Answer:

   Missing quotes around filename in save_screenshot -> Option C

4. Quick Check:

   Filename must be a string in quotes [OK]

Hint: Always put filename in quotes for save_screenshot [OK]

Common Mistakes:

• Forgetting quotes around filename string
• Changing method name incorrectly
• Misusing except syntax

5. You want to automatically take a screenshot only when a Selenium test fails and save it with a timestamp. Which approach below correctly implements this in Python?

hard

A. Use driver.save_screenshot('fail.png') outside try-except block

B. Use try-except around test steps, call driver.save_screenshot(f"fail_{time.time()}.png") in except

C. Call driver.save_screenshot() before every test step unconditionally

D. Use a loop to retry test steps and save screenshot on success

Solution

1. Step 1: Understand when to take screenshots

   Screenshots should be taken only on failure, inside except block.

2. Step 2: Use timestamp for unique filenames

   Using time.time() in filename ensures unique screenshot names.

3. Final Answer:

   Use try-except around test steps, call driver.save_screenshot(f"fail_{time.time()}.png") in except -> Option B

4. Quick Check:

   Screenshot on failure with timestamp = try-except + formatted filename [OK]

Hint: Take screenshots only in except block with timestamped names [OK]

Common Mistakes:

• Taking screenshots before test steps always
• Saving screenshots outside exception handling
• Retrying tests without capturing failure screenshots