Implementation:Microsoft Playwright BidiBrowser

Knowledge Sources	Microsoft_Playwright
Domains	Browser Automation, WebDriver BiDi Protocol
Last Updated	2026-02-12 00:00 GMT

Overview

Concrete tool for browser automation via the WebDriver BiDi protocol provided by the Playwright library.

Description

The `BidiBrowser` class extends the abstract `Browser` base class to implement browser control using the WebDriver BiDi (Bidirectional) protocol. It manages a `BidiConnection` and `BidiSession` for communicating with browsers that support the BiDi protocol (primarily Chromium and Firefox). The class handles session creation with capabilities negotiation (including proxy, insecure certs, and user prompt behavior), manages browser contexts (`BidiBrowserContext`), tracks pages via a map of browsing contexts to `BidiPage` instances, and implements browser lifecycle operations. The `BidiBrowserContext` inner class handles context-specific operations like cookie management, geolocation, and permissions.

Usage

Use this class when automating browsers through the WebDriver BiDi protocol, which provides a standardized, bidirectional communication channel for browser automation as an alternative to CDP (Chrome DevTools Protocol).

Code Reference

Source Location

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

Signature

export class BidiBrowser extends Browser {
  private readonly _connection: BidiConnection;
  readonly _browserSession: BidiSession;
  private _bidiSessionInfo!: bidi.Session.NewResult;
  readonly _contexts: Map<string, BidiBrowserContext>;
  readonly _bidiPages: Map<bidi.BrowsingContext.BrowsingContext, BidiPage>;

  static async connect(parent: SdkObject, transport: ConnectionTransport, options: BrowserOptions): Promise<BidiBrowser>;
  constructor(parent: SdkObject, transport: ConnectionTransport, options: BrowserOptions);
}

export class BidiBrowserContext extends BrowserContext {
  readonly _browser: BidiBrowser;
  constructor(browser: BidiBrowser, browserContextId: string | undefined, options: types.BrowserContextOptions);
}

Import

import { BidiBrowser, BidiBrowserContext } from '../server/bidi/bidiBrowser';

I/O Contract

Inputs

Name	Type	Required	Description
parent	SdkObject	Yes	Parent SDK object for instrumentation
transport	ConnectionTransport	Yes	WebSocket transport to the browser
options	BrowserOptions	Yes	Browser launch options including persistent context settings and proxy config

Outputs

Name	Type	Description
BidiBrowser	BidiBrowser	Connected browser instance ready for automation
BidiBrowserContext	BidiBrowserContext	Browser context for isolated browsing sessions
BidiPage	BidiPage	Page instance within a browser context

Usage Examples

import { BidiBrowser } from 'playwright-core/lib/server/bidi/bidiBrowser';

// Connect to a browser using BiDi protocol
const browser = await BidiBrowser.connect(parentSdkObject, wsTransport, {
  persistent: undefined,
  headful: true,
  proxy: { server: 'http://proxy:8080' },
});

const context = await browser.newContext();
const page = await context.newPage();
await page.goto('https://example.com');

Related Pages

• Environment:Microsoft_Playwright_Node_Runtime_Environment