Implementation:Microsoft Playwright BrowserContextDispatcher

Knowledge Sources	Microsoft_Playwright
Domains	RPC Protocol, Browser Context Management
Last Updated	2026-02-12 00:00 GMT

Overview

Concrete tool for exposing BrowserContext operations over the RPC protocol provided by the Playwright library.

Description

The `BrowserContextDispatcher` class bridges the server-side `BrowserContext` to the client via the RPC dispatcher system. It implements the `channels.BrowserContextChannel` interface, handling all context-level operations including page creation, cookie management, route interception, permission granting, storage state serialization, tracing, and recorder integration. The class manages event subscriptions (allowing clients to opt-in to specific events like console, dialog, request, response), maintains binding and init script registrations, handles WebSocket interception patterns, dialog handling, and clock control. It creates `PageDispatcher` instances for new pages and translates between protocol types and server types.

Usage

Use this dispatcher when the Playwright server needs to expose browser context capabilities to remote clients. It is created automatically when a client creates or connects to a browser context.

Code Reference

Source Location

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

Signature

export class BrowserContextDispatcher extends Dispatcher<BrowserContext, channels.BrowserContextChannel, DispatcherScope> implements channels.BrowserContextChannel {
  _type_EventTarget: true;
  _type_BrowserContext: true;
  private _context: BrowserContext;
  private _subscriptions: Set<channels.BrowserContextUpdateSubscriptionParams['event']>;

  constructor(parentScope: DispatcherScope, context: BrowserContext);
  async newPage(params: channels.BrowserContextNewPageParams): Promise<channels.BrowserContextNewPageResult>;
  async addCookies(params: channels.BrowserContextAddCookiesParams): Promise<void>;
  async clearCookies(params: channels.BrowserContextClearCookiesParams): Promise<void>;
  async setNetworkInterceptionPatterns(params: channels.BrowserContextSetNetworkInterceptionPatternsParams): Promise<void>;
  async storageState(params: channels.BrowserContextStorageStateParams): Promise<channels.BrowserContextStorageStateResult>;
  async close(params: channels.BrowserContextCloseParams): Promise<void>;
}

Import

import { BrowserContextDispatcher } from '../server/dispatchers/browserContextDispatcher';

I/O Contract

Inputs

Name	Type	Required	Description
parentScope	DispatcherScope	Yes	Parent dispatcher scope for object hierarchy
context	BrowserContext	Yes	Server-side browser context to expose
params	various channel params	Yes	Method-specific parameters from the client

Outputs

Name	Type	Description
PageDispatcher	PageDispatcher	Dispatcher for newly created pages
storageState	channels.BrowserContextStorageStateResult	Serialized cookies and storage
events	channel events	Page, console, dialog, request, response events

Usage Examples

// Created when a browser context is established
const contextDispatcher = new BrowserContextDispatcher(browserDispatcher, serverContext);

// Client calls are dispatched to the server context
const pageResult = await contextDispatcher.newPage({});
await contextDispatcher.addCookies({ cookies: [{ name: 'test', value: '1', url: 'https://example.com' }] });
const state = await contextDispatcher.storageState({});

Related Pages

• Environment:Microsoft_Playwright_Node_Runtime_Environment