playwright-mcp/src/browserContextFactory.ts
2025-06-04 09:14:50 -07:00

267 lines
10 KiB
TypeScript

/**
* Copyright (c) Microsoft Corporation.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import fs from 'node:fs';
import net from 'node:net';
import path from 'node:path';
import os from 'node:os';
import debug from 'debug';
import * as playwright from 'playwright';
import { userDataDir } from './fileUtils.js';
import type { FullConfig } from './config.js';
import type { BrowserInfo, LaunchBrowserRequest } from './browserAgent.js';
const testDebug = debug('pw:mcp:test');
export function contextFactory(browserConfig: FullConfig['browser']): BrowserContextFactory {
if (browserConfig.remoteEndpoint)
return new RemoteContextFactory(browserConfig);
if (browserConfig.cdpEndpoint)
return new CdpContextFactory(browserConfig);
if (browserConfig.isolated)
return new IsolatedContextFactory(browserConfig);
if (browserConfig.browserAgent)
return new AgentContextFactory(browserConfig);
return new PersistentContextFactory(browserConfig);
}
export interface BrowserContextFactory {
createContext(): Promise<{ browserContext: playwright.BrowserContext, close: () => Promise<void> }>;
}
class BaseContextFactory implements BrowserContextFactory {
readonly browserConfig: FullConfig['browser'];
protected _browserPromise: Promise<playwright.Browser> | undefined;
readonly name: string;
constructor(name: string, browserConfig: FullConfig['browser']) {
this.name = name;
this.browserConfig = browserConfig;
}
protected async _obtainBrowser(): Promise<playwright.Browser> {
if (this._browserPromise)
return this._browserPromise;
testDebug(`obtain browser (${this.name})`);
this._browserPromise = this._doObtainBrowser();
void this._browserPromise.then(browser => {
browser.on('disconnected', () => {
this._browserPromise = undefined;
});
}).catch(() => {
this._browserPromise = undefined;
});
return this._browserPromise;
}
protected async _doObtainBrowser(): Promise<playwright.Browser> {
throw new Error('Not implemented');
}
async createContext(): Promise<{ browserContext: playwright.BrowserContext, close: () => Promise<void> }> {
testDebug(`create browser context (${this.name})`);
const browser = await this._obtainBrowser();
const browserContext = await this._doCreateContext(browser);
return { browserContext, close: () => this._closeBrowserContext(browserContext, browser) };
}
protected async _doCreateContext(browser: playwright.Browser): Promise<playwright.BrowserContext> {
throw new Error('Not implemented');
}
private async _closeBrowserContext(browserContext: playwright.BrowserContext, browser: playwright.Browser) {
testDebug(`close browser context (${this.name})`);
if (browser.contexts().length === 1)
this._browserPromise = undefined;
await browserContext.close().catch(() => {});
if (browser.contexts().length === 0) {
testDebug(`close browser (${this.name})`);
await browser.close().catch(() => {});
}
}
}
class IsolatedContextFactory extends BaseContextFactory {
constructor(browserConfig: FullConfig['browser']) {
super('isolated', browserConfig);
}
protected override async _doObtainBrowser(): Promise<playwright.Browser> {
await injectCdpPort(this.browserConfig);
const browserType = playwright[this.browserConfig.browserName];
return browserType.launch({
...this.browserConfig.launchOptions,
handleSIGINT: false,
handleSIGTERM: false,
}).catch(error => {
if (error.message.includes('Executable doesn\'t exist'))
throw new Error(`Browser specified in your config is not installed. Either install it (likely) or change the config.`);
throw error;
});
}
protected override async _doCreateContext(browser: playwright.Browser): Promise<playwright.BrowserContext> {
return browser.newContext(this.browserConfig.contextOptions);
}
}
class CdpContextFactory extends BaseContextFactory {
constructor(browserConfig: FullConfig['browser']) {
super('cdp', browserConfig);
}
protected override async _doObtainBrowser(): Promise<playwright.Browser> {
return playwright.chromium.connectOverCDP(this.browserConfig.cdpEndpoint!);
}
protected override async _doCreateContext(browser: playwright.Browser): Promise<playwright.BrowserContext> {
return this.browserConfig.isolated ? await browser.newContext() : browser.contexts()[0];
}
}
class RemoteContextFactory extends BaseContextFactory {
constructor(browserConfig: FullConfig['browser']) {
super('remote', browserConfig);
}
protected override async _doObtainBrowser(): Promise<playwright.Browser> {
const url = new URL(this.browserConfig.remoteEndpoint!);
url.searchParams.set('browser', this.browserConfig.browserName);
if (this.browserConfig.launchOptions)
url.searchParams.set('launch-options', JSON.stringify(this.browserConfig.launchOptions));
return playwright[this.browserConfig.browserName].connect(String(url));
}
protected override async _doCreateContext(browser: playwright.Browser): Promise<playwright.BrowserContext> {
return browser.newContext();
}
}
class PersistentContextFactory implements BrowserContextFactory {
readonly browserConfig: FullConfig['browser'];
private _userDataDirs = new Set<string>();
constructor(browserConfig: FullConfig['browser']) {
this.browserConfig = browserConfig;
}
async createContext(): Promise<{ browserContext: playwright.BrowserContext, close: () => Promise<void> }> {
await injectCdpPort(this.browserConfig);
testDebug('create browser context (persistent)');
const userDataDir = this.browserConfig.userDataDir ?? await this._createUserDataDir();
this._userDataDirs.add(userDataDir);
testDebug('lock user data dir', userDataDir);
const browserType = playwright[this.browserConfig.browserName];
for (let i = 0; i < 5; i++) {
try {
const browserContext = await browserType.launchPersistentContext(userDataDir, {
...this.browserConfig.launchOptions,
...this.browserConfig.contextOptions,
handleSIGINT: false,
handleSIGTERM: false,
});
const close = () => this._closeBrowserContext(browserContext, userDataDir);
return { browserContext, close };
} catch (error: any) {
if (error.message.includes('Executable doesn\'t exist'))
throw new Error(`Browser specified in your config is not installed. Either install it (likely) or change the config.`);
if (error.message.includes('ProcessSingleton') || error.message.includes('Invalid URL')) {
// User data directory is already in use, try again.
await new Promise(resolve => setTimeout(resolve, 1000));
continue;
}
throw error;
}
}
throw new Error(`Browser is already in use for ${userDataDir}, use --isolated to run multiple instances of the same browser`);
}
private async _closeBrowserContext(browserContext: playwright.BrowserContext, userDataDir: string) {
testDebug('close browser context (persistent)');
testDebug('release user data dir', userDataDir);
await browserContext.close().catch(() => {});
this._userDataDirs.delete(userDataDir);
testDebug('close browser context complete (persistent)');
}
private async _createUserDataDir() {
let cacheDirectory: string;
if (process.platform === 'linux')
cacheDirectory = process.env.XDG_CACHE_HOME || path.join(os.homedir(), '.cache');
else if (process.platform === 'darwin')
cacheDirectory = path.join(os.homedir(), 'Library', 'Caches');
else if (process.platform === 'win32')
cacheDirectory = process.env.LOCALAPPDATA || path.join(os.homedir(), 'AppData', 'Local');
else
throw new Error('Unsupported platform: ' + process.platform);
const result = path.join(cacheDirectory, 'ms-playwright', `mcp-${this.browserConfig.launchOptions?.channel ?? this.browserConfig?.browserName}-profile`);
await fs.promises.mkdir(result, { recursive: true });
return result;
}
}
export class AgentContextFactory extends BaseContextFactory {
constructor(browserConfig: FullConfig['browser']) {
super('persistent', browserConfig);
}
protected override async _doObtainBrowser(): Promise<playwright.Browser> {
const response = await fetch(new URL(`/json/launch`, this.browserConfig.browserAgent), {
method: 'POST',
body: JSON.stringify({
browserType: this.browserConfig.browserName,
userDataDir: this.browserConfig.userDataDir ?? await this._createUserDataDir(),
launchOptions: this.browserConfig.launchOptions,
contextOptions: this.browserConfig.contextOptions,
} as LaunchBrowserRequest),
});
const info = await response.json() as BrowserInfo;
if (info.error)
throw new Error(info.error);
return await playwright.chromium.connectOverCDP(`http://localhost:${info.cdpPort}/`);
}
protected override async _doCreateContext(browser: playwright.Browser): Promise<playwright.BrowserContext> {
return this.browserConfig.isolated ? await browser.newContext() : browser.contexts()[0];
}
private async _createUserDataDir() {
const dir = await userDataDir(this.browserConfig);
await fs.promises.mkdir(dir, { recursive: true });
return dir;
}
}
async function injectCdpPort(browserConfig: FullConfig['browser']) {
if (browserConfig.browserName === 'chromium')
(browserConfig.launchOptions as any).cdpPort = await findFreePort();
}
async function findFreePort() {
return new Promise((resolve, reject) => {
const server = net.createServer();
server.listen(0, () => {
const { port } = server.address() as net.AddressInfo;
server.close(() => resolve(port));
});
server.on('error', reject);
});
}