Implementation:Microsoft Playwright Server Browser

Knowledge Sources	Microsoft_Playwright
Domains	Server, Browser
Last Updated	2026-02-12 00:00 GMT

Overview

Concrete tool for defining the abstract base class for all browser implementations on the server side provided by the Playwright library.

Description

The `Browser` abstract class extends `SdkObject` and serves as the base for all browser engine implementations (Chromium, Firefox, WebKit). It defines the `BrowserOptions` type containing launch configuration (name, channel, artifact directories, browser process, proxy settings, protocol logger, etc.) and the `BrowserProcess` interface for managing the underlying browser process. The class provides abstract methods for context management (`newContext`, `contexts`, `isConnected`), version information (`version`), and lifecycle control. It emits `Context` and `Disconnected` events, handles download management with `Artifact` instances, and coordinates browser context creation with `validateBrowserContextOptions`.

Usage

Use Server Browser as the base class when implementing a new browser engine backend, or when working with browser instances generically across Chromium, Firefox, and WebKit.

Code Reference

Source Location

• Repository: Microsoft_Playwright
• File: packages/playwright-core/src/server/browser.ts

Signature

export interface BrowserProcess {
  onclose?: ((exitCode: number | null, signal: string | null) => void);
  process?: ChildProcess;
  kill(): Promise<void>;
  close(): Promise<void>;
}

export type BrowserOptions = {
  name: string;
  isChromium: boolean;
  channel?: string;
  artifactsDir: string;
  downloadsPath: string;
  tracesDir: string;
  headful?: boolean;
  persistent?: types.BrowserContextOptions;
  browserProcess: BrowserProcess;
  // ... additional options
};

export abstract class Browser extends SdkObject {
  static Events: { Context: string; Disconnected: string };
  readonly options: BrowserOptions;
  abstract newContext(options: types.BrowserContextOptions): Promise<BrowserContext>;
  abstract contexts(): BrowserContext[];
  abstract isConnected(): boolean;
  abstract version(): string;
}

Import

import { Browser } from '../server/browser';
import type { BrowserOptions, BrowserProcess } from '../server/browser';

I/O Contract

Inputs

Name	Type	Required	Description
parent	SdkObject	Yes	Parent SDK object for instrumentation hierarchy
options	BrowserOptions	Yes	Full browser configuration including process, paths, and logging

Outputs

Name	Type	Description
context	BrowserContext	Newly created browser context
contexts	BrowserContext[]	All active browser contexts
version	string	Browser version string

Usage Examples

import { Browser } from '../server/browser';

// Browser is abstract; use via subclasses like CRBrowser, BidiBrowser, WKBrowser
const context = await browser.newContext({
  viewport: { width: 1280, height: 720 },
  userAgent: 'custom-agent',
});
const contexts = browser.contexts();
console.log('Browser version:', browser.version());

Related Pages

• Environment:Microsoft_Playwright_Node_Runtime_Environment