puppeteer/src/node/NodeWebSocketTransport.ts

/**
 * Copyright 2018 Google Inc. All rights reserved.
 *
 * 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 NodeWebSocket from 'ws';
import { ConnectionTransport } from '../common/ConnectionTransport.js';
import { packageVersion } from '../generated/version.js';
import { promises as dns } from 'dns';

export class NodeWebSocketTransport implements ConnectionTransport {
  static async create(urlString: string): Promise<NodeWebSocketTransport> {
    // TODO(jrandolf): Starting in Node 17, IPv6 is favoured over IPv4 due to a change
    // in a default option:
    // - https://github.com/nodejs/node/issues/40537,
    // Due to this, for Firefox, we must parse and resolve the `localhost` hostname
    // manually with the previous behavior according to:
    // - https://nodejs.org/api/dns.html#dnslookuphostname-options-callback
    // because of https://bugzilla.mozilla.org/show_bug.cgi?id=1769994.
    const url = new URL(urlString);
    if (url.hostname === 'localhost') {
      const { address } = await dns.lookup(url.hostname, { verbatim: false });
      url.hostname = address;
    }

    return new Promise((resolve, reject) => {
      const ws = new NodeWebSocket(url, [], {
        followRedirects: true,
        perMessageDeflate: false,
        maxPayload: 256 * 1024 * 1024, // 256Mb
        headers: {
          'User-Agent': `Puppeteer ${packageVersion}`,
        },
      });

      ws.addEventListener('open', () =>
        resolve(new NodeWebSocketTransport(ws))
      );
      ws.addEventListener('error', reject);
    });
  }

  private _ws: NodeWebSocket;
  onmessage?: (message: NodeWebSocket.Data) => void;
  onclose?: () => void;

  constructor(ws: NodeWebSocket) {
    this._ws = ws;
    this._ws.addEventListener('message', (event) => {
      if (this.onmessage) this.onmessage.call(null, event.data);
    });
    this._ws.addEventListener('close', () => {
      if (this.onclose) this.onclose.call(null);
    });
    // Silently ignore all errors - we don't know what to do with them.
    this._ws.addEventListener('error', () => {});
  }

  send(message: string): void {
    this._ws.send(message);
  }

  close(): void {
    this._ws.close();
  }
}