feat: add Page.opener() to the API (#790)

Fixes #783

Author: yury-s

docs/api.md

@@ -467,6 +467,7 @@ page.removeListener('request', logRequest);
 - [page.keyboard](#pagekeyboard)
 - [page.mainFrame()](#pagemainframe)
 - [page.mouse](#pagemouse)
+- [page.opener()](#pageopener)
 - [page.pdf([options])](#pagepdfoptions)
 - [page.reload([options])](#pagereloadoptions)
 - [page.screenshot([options])](#pagescreenshotoptions)
@@ -1098,6 +1099,10 @@ Page is guaranteed to have a main frame which persists during navigations.
 
 - returns: <[Mouse]>
 
+#### page.opener()
+
+- returns: <[Promise]<?[Page]>> Promise which resolves to the opener for popup pages and `null` for others. If the opener has been closed already the promise may resolve to `null`.
+
 #### page.pdf([options])
 - `options` <[Object]> Options object which might have the following properties:
   - `path` <[string]> The file path to save the PDF to. If `path` is a relative path, then it is resolved relative to [current working directory](https://nodejs.org/api/process.html#process_process_cwd). If no path is provided, the PDF won't be saved to the disk.

src/chromium/crPage.ts

@@ -38,6 +38,7 @@ import { BrowserContext } from '../browserContext';
 import * as types from '../types';
 import { ConsoleMessage } from '../console';
 import * as platform from '../platform';
+import { CRTarget } from './crTarget';
 
 const UTILITY_WORLD_NAME = '__playwright_utility_world__';
 
@@ -349,6 +350,13 @@ export class CRPage implements PageDelegate {
     await this._client.send('Page.setInterceptFileChooserDialog', { enabled }).catch(e => {}); // target can be closed.
   }
 
+  async opener() : Promise<Page | null> {
+    const openerTarget = CRTarget.fromPage(this._page).opener();
+    if (!openerTarget)
+      return null;
+    return await openerTarget.page();
+  }
+
   async reload(): Promise<void> {
     await this._client.send('Page.reload');
   }

src/firefox/ffBrowser.ts

@@ -280,7 +280,12 @@ class Target {
     if (!this._pagePromise) {
       this._pagePromise = new Promise(async f => {
         const session = await this._connection.createSession(this._targetId);
-        this._ffPage = new FFPage(session, this._context);
+        this._ffPage = new FFPage(session, this._context, async () => {
+          const openerTarget = this.opener();
+          if (!openerTarget)
+            return null;
+          return await openerTarget.page();
+        });
         const page = this._ffPage._page;
         session.once(FFSessionEvents.Disconnected, () => page._didDisconnect());
         await this._ffPage._initialize();

src/firefox/ffPage.ts

@@ -41,12 +41,14 @@ export class FFPage implements PageDelegate {
   readonly _session: FFSession;
   readonly _page: Page;
   readonly _networkManager: FFNetworkManager;
+  private readonly _openerResolver: () => Promise<Page | null>;
   private readonly _contextIdToContext: Map<string, dom.FrameExecutionContext>;
   private _eventListeners: RegisteredListener[];
   private _workers = new Map<string, { frameId: string, session: FFSession }>();
 
-  constructor(session: FFSession, browserContext: BrowserContext) {
+  constructor(session: FFSession, browserContext: BrowserContext, openerResolver: () => Promise<Page | null>) {
     this._session = session;
+    this._openerResolver = openerResolver;
     this.rawKeyboard = new RawKeyboardImpl(session);
     this.rawMouse = new RawMouseImpl(session);
     this._contextIdToContext = new Map();
@@ -305,6 +307,10 @@ export class FFPage implements PageDelegate {
     await this._session.send('Page.setInterceptFileChooserDialog', { enabled }).catch(e => {}); // target can be closed.
   }
 
+  async opener() : Promise<Page | null> {
+    return await this._openerResolver();
+  }
+
   async reload(): Promise<void> {
     await this._session.send('Page.reload', { frameId: this._page.mainFrame()._id });
   }

src/page.ts

@@ -34,6 +34,8 @@ export interface PageDelegate {
   readonly rawMouse: input.RawMouse;
   readonly rawKeyboard: input.RawKeyboard;
 
+  opener(): Promise<Page | null>;
+
   reload(): Promise<void>;
   goBack(): Promise<boolean>;
   goForward(): Promise<boolean>;
@@ -173,6 +175,10 @@ export class Page extends platform.EventEmitter {
     return this._browserContext;
   }
 
+  async opener(): Promise<Page | null> {
+    return await this._delegate.opener();
+  }
+
   mainFrame(): frames.Frame {
     return this._frameManager.mainFrame();
   }

src/webkit/wkBrowser.ts

@@ -113,7 +113,14 @@ export class WKBrowser extends platform.EventEmitter implements Browser {
     const pageProxySession = new WKSession(this._connection, pageProxyId, `The page has been closed.`, (message: any) => {
       this._connection.rawSend({ ...message, pageProxyId });
     });
-    const pageProxy = new WKPageProxy(pageProxySession, context);
+    const pageProxy = new WKPageProxy(pageProxySession, context, () => {
+      if (!pageProxyInfo.openerId)
+        return null;
+      const opener = this._pageProxies.get(pageProxyInfo.openerId);
+      if (!opener)
+        return null;
+      return opener;
+    });
     this._pageProxies.set(pageProxyId, pageProxy);
 
     if (pageProxyInfo.openerId) {

src/webkit/wkPage.ts

@@ -45,15 +45,17 @@ export class WKPage implements PageDelegate {
   private _provisionalPage: WKProvisionalPage | null = null;
   readonly _page: Page;
   private readonly _pageProxySession: WKSession;
+  private readonly _openerResolver: () => Promise<Page | null>;
   private readonly _requestIdToRequest = new Map<string, WKInterceptableRequest>();
   private readonly _workers: WKWorkers;
   private readonly _contextIdToContext: Map<number, dom.FrameExecutionContext>;
   private _mainFrameContextId?: number;
   private _sessionListeners: RegisteredListener[] = [];
   private readonly _bootstrapScripts: string[] = [];
 
-  constructor(browserContext: BrowserContext, pageProxySession: WKSession) {
+  constructor(browserContext: BrowserContext, pageProxySession: WKSession, openerResolver: () => Promise<Page | null>) {
     this._pageProxySession = pageProxySession;
+    this._openerResolver = openerResolver;
     this.rawKeyboard = new RawKeyboardImpl(pageProxySession);
     this.rawMouse = new RawMouseImpl(pageProxySession);
     this._contextIdToContext = new Map();
@@ -415,6 +417,10 @@ export class WKPage implements PageDelegate {
     await this._session.send('Page.setInterceptFileChooserDialog', { enabled }).catch(e => {}); // target can be closed.
   }
 
+  async opener() {
+    return await this._openerResolver();
+  }
+
   async reload(): Promise<void> {
     await this._session.send('Page.reload');
   }

src/webkit/wkPageProxy.ts

@@ -28,6 +28,7 @@ const isPovisionalSymbol = Symbol('isPovisional');
 export class WKPageProxy {
   private readonly _pageProxySession: WKSession;
   readonly _browserContext: BrowserContext;
+  private readonly _openerResolver: () => WKPageProxy | null;
   private _pagePromise: Promise<Page> | null = null;
   private _wkPage: WKPage | null = null;
   private readonly _firstTargetPromise: Promise<void>;
@@ -36,9 +37,10 @@ export class WKPageProxy {
   private readonly _sessions = new Map<string, WKSession>();
   private readonly _eventListeners: RegisteredListener[];
 
-  constructor(pageProxySession: WKSession, browserContext: BrowserContext) {
+  constructor(pageProxySession: WKSession, browserContext: BrowserContext, openerResolver: () => (WKPageProxy | null)) {
     this._pageProxySession = pageProxySession;
     this._browserContext = browserContext;
+    this._openerResolver = openerResolver;
     this._firstTargetPromise = new Promise(r => this._firstTargetCallback = r);
     this._eventListeners = [
       helper.addEventListener(this._pageProxySession, 'Target.targetCreated', this._onTargetCreated.bind(this)),
@@ -111,7 +113,12 @@ export class WKPageProxy {
       }
     }
     assert(session, 'One non-provisional target session must exist');
-    this._wkPage = new WKPage(this._browserContext, this._pageProxySession);
+    this._wkPage = new WKPage(this._browserContext, this._pageProxySession, async () => {
+      const pageProxy = this._openerResolver();
+      if (!pageProxy)
+        return null;
+      return await pageProxy.page();
+    });
     await this._wkPage.initialize(session!);
     if (this._pagePausedOnStart) {
       this._resumeTarget(session!.sessionId);

test/page.spec.js

@@ -186,6 +186,26 @@ module.exports.describe = function({testRunner, expect, headless, playwright, FF
     });
   });
 
+  describe('Page.opener', function() {
+    it('should provide access to the opener page', async({page}) => {
+      const [popup] = await Promise.all([
+        new Promise(x => page.once('popup', x)),
+        page.evaluate(() => window.open('about:blank')),
+      ]);
+      const opener = await popup.opener();
+      expect(opener).toBe(page);
+    });
+    it('should return null if parent page has been closed', async({page}) => {
+      const [popup] = await Promise.all([
+        new Promise(x => page.once('popup', x)),
+        page.evaluate(() => window.open('about:blank')),
+      ]);
+      await page.close();
+      const opener = await popup.opener();
+      expect(opener).toBe(null);
+    });
+  });
+
   describe('Page.Events.Console', function() {
     it('should work', async({page, server}) => {
       let message = null;