Implementation:Microsoft Playwright PlaywrightServer

Knowledge Sources	Microsoft_Playwright
Domains	Remote Execution, WebSocket Server
Last Updated	2026-02-12 00:00 GMT

Overview

Concrete tool for hosting a remote Playwright WebSocket server provided by the Playwright library.

Description

The `PlaywrightServer` class manages a WebSocket-based server that allows remote clients to connect and control browser instances. It supports multiple operational modes: `default` (full Playwright access), `launchServer` (single browser launch), `launchServerShared` (shared browser reuse), and `extension` (for browser extension development). The server uses a `WSServer` for WebSocket handling, a `Semaphore` for connection limiting, and can accept pre-launched browsers, Android devices, or SOCKS proxies. Browser reuse logic prevents disposing browsers that should persist across connections.

Usage

Use this class when you need to run Playwright in a server mode that accepts remote WebSocket connections, such as when running browsers on a remote machine, sharing browser instances across test workers, or enabling the Playwright extension development workflow.

Code Reference

Source Location

• Repository: Microsoft_Playwright
• File: packages/playwright-core/src/remote/playwrightServer.ts

Signature

type ServerOptions = {
  path: string;
  maxConnections: number;
  mode: 'default' | 'launchServer' | 'launchServerShared' | 'extension';
  preLaunchedBrowser?: Browser;
  preLaunchedAndroidDevice?: AndroidDevice;
  preLaunchedSocksProxy?: SocksProxy;
};

export class PlaywrightServer {
  private _playwright: Playwright;
  private _options: ServerOptions;
  private _wsServer: WSServer;
  private _dontReuseBrowsers: Set<Browser>;

  constructor(options: ServerOptions);
  async listen(port?: number): Promise<string>;
  async close(): Promise<void>;
}

Import

import { PlaywrightServer } from 'playwright-core/lib/remote/playwrightServer';

I/O Contract

Inputs

Name	Type	Required	Description
options.path	string	Yes	WebSocket endpoint path
options.maxConnections	number	Yes	Maximum number of concurrent WebSocket connections
options.mode	string	Yes	Server operating mode (default, launchServer, launchServerShared, extension)
options.preLaunchedBrowser	Browser	No	Pre-launched browser instance to serve
options.preLaunchedAndroidDevice	AndroidDevice	No	Pre-launched Android device to serve
options.preLaunchedSocksProxy	SocksProxy	No	Pre-launched SOCKS proxy for network routing
port	number	No	TCP port to listen on (passed to listen method)

Outputs

Name	Type	Description
wsEndpoint	string	The WebSocket URL that clients can connect to

Usage Examples

import { PlaywrightServer } from 'playwright-core/lib/remote/playwrightServer';

const server = new PlaywrightServer({
  path: '/ws',
  maxConnections: 10,
  mode: 'default',
});

const wsEndpoint = await server.listen(3000);
console.log('Playwright server listening at:', wsEndpoint);

// Clients can now connect:
// const browser = await playwright.chromium.connect(wsEndpoint);

await server.close();

Related Pages

• Environment:Microsoft_Playwright_Node_Runtime_Environment