In this article we cover how do we capture performance metrics from the page during test run using CDP’s(Chrome DevTool Protocol) Performance domain in Playwright.
Chrome DevTool Protocol
The Chrome DevTools Protocol allows for tools to instrument, inspect, debug and profile Chromium, Chrome and other Blink-based browsers. Many existing projects currently use the protocol.
Instrumentation is divided into a number of domains (DOM, Debugger, Network etc.). Each domain defines a number of commands it supports and events it generates. Both commands and events are serialized JSON objects of a fixed structure.
Protocol Domains
Chrome DevTools Protocol is divided into domains. Each domain has a set of commands and events that it supports.
For example, the Network domain contains APIs for accessing the HTTP requests and responses made when rendering a page. The DOM (Document Object Model) domain. It exposes APIs for reading from and writing to the DOM. You can access query selectors, get element attributes, manipulate nodes and even scroll to selected nodes. Another useful domain is Performance…
