[rb] Add support for full page screenshots in Chrome and Edge

[jspanjers]

User description

🔗 Related Issues

Provides a quickfix for #14116.

💥 What does this PR do?

Implements full page screenshots for Chromium browsers for the Ruby language.

It extends the Chromium driver with full page screenshot functionality, similar to how it was implemented before for the Firefox driver. It uses Chrome's session/:session_id/screenshot/full endpoint.

🔧 Implementation Notes

Issue #14116 was originally opened to raise the issue that full page screenshots are not working for the ruby bindings in Chrome/Edge using driver.save_screenshot(path, full_page: true). This is fixed here.

💡 Additional Considerations

In Issue #14116 there is discussion about rewriting Selenium's screenshot functionality to use BiDi, and changing the API to something like driver.page.screenshot(params). I believe rewriting to use BiDi can be done later, as well as changing the API. I am also not sure that there is a specification for taking full page screenshots with BiDi yet.

🔄 Types of changes

• New feature (non-breaking change which adds functionality and tests!)

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PR Type

Enhancement

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Description

• Adds full page screenshot support for Chrome in Ruby bindings

• Implements full_screenshot method in Chromium driver bridge

• Registers new full_page_screenshot endpoint for Chrome driver

• Includes integration test validating full page screenshot functionality

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Diagram Walkthrough

flowchart LR
  A["Chrome Driver"] -->|extends with| B["FullPageScreenshot Extension"]
  B -->|calls| C["full_screenshot method"]
  C -->|executes| D["session/:session_id/screenshot/full endpoint"]
  D -->|returns| E["Full page screenshot PNG"]

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File Walkthrough

	Relevant files
Enhancement	driver.rb Register FullPageScreenshot extension in Chromium driver  rb/lib/selenium/webdriver/chromium/driver.rb Adds DriverExtensions::FullPageScreenshot to the EXTENSIONS list for Chromium driver Enables full page screenshot functionality for Chrome and Edge drivers +1/-0      features.rb Implement full page screenshot bridge and endpoint              rb/lib/selenium/webdriver/chromium/features.rb Adds full_page_screenshot command mapping to Chrome's screenshot/full endpoint Implements full_screenshot method in Bridge module to execute the command Enables direct access to Chrome's native full page screenshot capability +6/-1
Tests	driver_spec.rb Add full page screenshot integration test                                rb/spec/integration/selenium/webdriver/chrome/driver_spec.rb Adds integration test for full page screenshot functionality Verifies screenshot height exceeds viewport height for full page capture Tests save_screenshot with full_page: true parameter Validates PNG file creation and size +13/-0

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[CLAassistant]

All committers have signed the CLA.

[qodo-code-review]

PR Compliance Guide 🔍

Below is a summary of compliance checks for this PR:

Security Compliance
🟢	No security concerns identified No security vulnerabilities detected by AI analysis. Human verification advised for critical code.
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⚪	🎫 No ticket provided Create ticket/issue
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🟢	Generic: Meaningful Naming and Self-Documenting Code Objective: Ensure all identifiers clearly express their purpose and intent, making code self-documenting Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Secure Error Handling Objective: To prevent the leakage of sensitive system information through error messages while providing sufficient detail for internal debugging. Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Secure Logging Practices Objective: To ensure logs are useful for debugging and auditing without exposing sensitive information like PII, PHI, or cardholder data. Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Security-First Input Validation and Data Handling Objective: Ensure all data inputs are validated, sanitized, and handled securely to prevent vulnerabilities Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
⚪	Generic: Comprehensive Audit Trails Objective: To create a detailed and reliable record of critical system actions for security analysis and compliance. Status: No auditing: The new full page screenshot action is introduced without any explicit audit logging, though this SDK code may rely on higher-level logging not shown in the diff. Referred Code def full_screenshot execute :full_page_screenshot end Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Robust Error Handling and Edge Case Management Objective: Ensure comprehensive error handling that provides meaningful context and graceful degradation Status: Missing handling: The new full_screenshot command delegates directly to execute without explicit error handling or edge case management, which may be acceptable if execute handles errors centrally. Referred Code def full_screenshot execute :full_page_screenshot end Learn more about managing compliance generic rules or creating your own custom rules
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[qodo-code-review]

PR Code Suggestions ✨

Explore these optional code suggestions:

Category	Suggestion	Impact
General	✅ Verify screenshot file was created Suggestion Impact: The commit added assertions checking File.exist?(path) and File.size(path).to be_positive around the screenshot save operation, aligning with the suggestion. code diff: expect(File.exist?(path)).to be true expect(File.size(path)).to be_positive Add assertions to the save_screenshot test to verify that the screenshot file is created on disk and has a size greater than zero. rb/spec/integration/selenium/webdriver/chrome/driver_spec.rb [94-98] path = "#{Dir.tmpdir}/test#{SecureRandom.urlsafe_base64}.png" screenshot = driver.save_screenshot(path, full_page: true) + +expect(File.exist?(path)).to be true +expect(File.size(path)).to be_positive _width, height = png_size(screenshot) expect(height).to be > viewport_height [Suggestion processed] Suggestion importance[1-10]: 6 __ Why: The suggestion correctly identifies an omission in the new test case; it fails to verify that save_screenshot actually creates a file, which is a primary function of the method being tested.	Low
Update

[cgoldberg]

interesting... has Chrome always supported this? The reason in #14116 that this was Firefox-only was that Chrome didn't provide this endpoint.

If this now works, I'm going to add the same thing in the Python bindings.

[cgoldberg]

@jspanjers Edge browser inherits this same functionality and it probably works there also. Can you add the same test for that?

[cgoldberg]

why this change?

[cgoldberg]

@jspanjers can you check the failed screenshot tests in CI?

[titusfortner]

Firstly, thank you for tracking down the implementation details for this and submitting a code fix.

The problem with the screenshot endpoint in Chrome (and Edge) is that it is not w3c compliant. It must be namespaced correctly for us to implement it. I requested it be updated by them several years ago and they declined - https://issues.chromium.org/issues/42322971

Also, the log endpoint is no longer supported, so we can't add that back, either.

We hope to have a better future-compatible implementation for this soon using the w3c WebDriver BiDi specification.