puppeteer/src/common/Dialog.ts

/**
 * Copyright 2017 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 { assert } from './assert';
import { CDPSession } from './Connection';
import Protocol from '../protocol';

/**
 * Dialog instances are dispatched by the {@link Page} via the `dialog` event.
 *
 * @remarks
 *
 * @example
 * ```js
 * const puppeteer = require('puppeteer');
 *
 * (async () => {
 *   const browser = await puppeteer.launch();
 *   const page = await browser.newPage();
 *   page.on('dialog', async dialog => {
 *     console.log(dialog.message());
 *     await dialog.dismiss();
 *     await browser.close();
 *   });
 *   page.evaluate(() => alert('1'));
 * })();
 * ```
 */
export class Dialog {
  private _client: CDPSession;
  private _type: Protocol.Page.DialogType;
  private _message: string;
  private _defaultValue: string;
  private _handled = false;

  /**
   * @internal
   */
  constructor(
    client: CDPSession,
    type: Protocol.Page.DialogType,
    message: string,
    defaultValue = ''
  ) {
    this._client = client;
    this._type = type;
    this._message = message;
    this._defaultValue = defaultValue;
  }

  /**
   * @returns The type of the dialog.
   */
  type(): Protocol.Page.DialogType {
    return this._type;
  }

  /**
   * @returns The message displayed in the dialog.
   */
  message(): string {
    return this._message;
  }

  /**
   * @returns The default value of the prompt, or an empty string if the dialog is not a `prompt`.
   */
  defaultValue(): string {
    return this._defaultValue;
  }

  /**
   * @param promptText - optional text that will be entered in the dialog prompt. Has no effect if the dialog's type is not `prompt`.
   * @returns A promise that resolves when the dialog has been accepted.
   */
  async accept(promptText?: string): Promise<void> {
    assert(!this._handled, 'Cannot accept dialog which is already handled!');
    this._handled = true;
    await this._client.send('Page.handleJavaScriptDialog', {
      accept: true,
      promptText: promptText,
    });
  }

  /**
   * @returns A promise which will resolve once the dialog has been dismissed
   */
  async dismiss(): Promise<void> {
    assert(!this._handled, 'Cannot dismiss dialog which is already handled!');
    this._handled = true;
    await this._client.send('Page.handleJavaScriptDialog', {
      accept: false,
    });
  }
}