Selenium 4 Chrome DevTools Examples

A few Selenium CDP examples in the Ruby language

This article is included in my “How to in Selenium WebDriver” series.

Selenium WebDriver 4 supports Chrome DevTools Protocol(CDP), enabling a debugger inside Chromium-based browsers. By the way, Cypress and Puppeteer are based on CDP. CDP has some issues and limitations, not surprisingly, it is a debugging protocol after all.

In this article, I will show some DevTools examples with the new Selenium 4.

Table of Contents:
· General
  ∘ Navigate to a URL
  ∘ Print to PDF
  ∘ Get browser Client Size
  ∘ Get browser info
  ∘  Execute CDP Command
· Event
  ∘ Console log messages
· Network
  ∘ Basic Authentication
· Emulate
  ∘ GEO Location
· Page
  ∘ Download file
  ∘ Navigation history
· Summary

While Selenium 4 supports CDP, it is not included by default. You need to install a separate gem ( ruby library):

> gem install — no-document selenium-devtools
Successfully installed selenium-devtools-0.94.0
1 gem installed

You will see the first limitation, CDP is associated with a particular version of Chrome. For example, I got the following error after the Chrome browser self-updated to v95.

Failure/Error…