Introduce Page.waitForNavigation (#94)

This patch introduces Page.waitForNavigation which allows to wait
for render-initiated navigation.

This patch also does a nice refactoring, replacing Navigator with NavigatorWatcher which
is not a part of a page state.

References #89

docs/api.md

@@ -42,7 +42,7 @@
   * [page.navigate(url, options)](#pagenavigateurl-options)
   * [page.pdf(options)](#pagepdfoptions)
   * [page.plainText()](#pageplaintext)
-  * [page.reload()](#pagereload)
+  * [page.reload(options)](#pagereloadoptions)
   * [page.screenshot([options])](#pagescreenshotoptions)
   * [page.setContent(html)](#pagesetcontenthtml)
   * [page.setHTTPHeaders(headers)](#pagesethttpheadersheaders)
@@ -57,6 +57,7 @@
   * [page.userAgent()](#pageuseragent)
   * [page.viewport()](#pageviewport)
   * [page.waitFor(selector)](#pagewaitforselector)
+  * [page.waitForNavigation(options)](#pagewaitfornavigationoptions)
 - [class: Keyboard](#class-keyboard)
   * [keyboard.hold(key[, options])](#keyboardholdkey-options)
   * [keyboard.modifiers()](#keyboardmodifiers)
@@ -422,7 +423,8 @@ The `format` options are:
 #### page.plainText()
 - returns:  <[Promise]<[string]>> Returns page's inner text.
 
-#### page.reload()
+#### page.reload(options)
+- `options` <[Object]> Navigation parameters, same as in [page.navigate](#pagenavigateurl-options).
 - returns: <[Promise]<[Response]>> Promise which resolves to the main resource response. In case of multiple redirects, the navigation will resolve with the response of the last redirect.
 
 #### page.screenshot([options])
@@ -535,6 +537,10 @@ This is a shortcut for [page.mainFrame().url()](#frameurl)
 - `selector` <[string]> A query selector to wait for on the page.
 - returns: <[Promise]> Promise which resolves when the element matching `selector` appears in the page.
 
+#### page.waitForNavigation(options)
+- `options` <[Object]> Navigation parameters, same as in [page.navigate](#pagenavigateurl-options).
+- returns: <[Promise]<[Response]>> Promise which resolves to the main resource response. In case of multiple redirects, the navigation will resolve with the response of the last redirect.
+
 Shortcut for [page.mainFrame().waitFor(selector)](#framewaitforselector).
 
 ### class: Keyboard

lib/NavigatorWatcher.js

@@ -14,30 +14,31 @@
  * limitations under the License.
  */
 
-class Navigator {
+const NetworkManager = require('./NetworkManager');
+
+class NavigatorWatcher {
   /**
    * @param {!Connection} client
-   * @param {string} url
-   * @param {string=} referrer
+   * @param {!NetworkManager} networkManager
    * @param {!Object=} options
    */
-  constructor(client, url, referrer, options = {}) {
+  constructor(client, networkManager, options = {}) {
     this._client = client;
-    this._url = url;
-    this._referrer = referrer;
+    this._networkManager = networkManager;
     this._maxTime = typeof options['maxTime'] === 'number' ? options['maxTime'] : 30000;
     this._idleTime = typeof options['networkIdleTimeout'] === 'number' ? options['networkIdleTimeout'] : 1000;
     this._idleInflight = typeof options['networkIdleInflight'] === 'number' ? options['networkIdleInflight'] : 2;
     this._waitUntil = typeof options['waitUntil'] === 'string' ? options['waitUntil'] : 'load';
-
     console.assert(this._waitUntil === 'load' || this._waitUntil === 'networkidle', 'Unknown value for options.waitUntil: ' + this._waitUntil);
   }
 
+
   /**
-   * @return {!Promise}
+   * @return {!Promise<!Map<string, !Response>>}
    */
-  async navigate() {
+  async waitForNavigation() {
     this._init();
+
     let certificateError = new Promise(fulfill => this._client.once('Security.certificateError', fulfill))
         .then(error => new Error('SSL Certiciate error: ' + error.errorType));
     let networkIdle = new Promise(fulfill => this._networkIdleCallback = fulfill).then(() => null);
@@ -46,15 +47,19 @@ class Navigator {
 
     try {
       // Await for the command to throw exception in case of illegal arguments.
-      await this._client.send('Page.navigate', {url: this._url, referrer: this._referrer});
       const error = await Promise.race([certificateError, watchdog, this._waitUntil === 'load' ? loadEventFired : networkIdle]);
       if (error)
         throw error;
+      return this._responses;
     } finally {
       this._cleanup();
     }
   }
 
+  cancel() {
+    this._cleanup();
+  }
+
   /**
    * @param {!Object} event
    */
@@ -83,14 +88,18 @@ class Navigator {
   _init() {
     this._loadingStartedHandler = this._onLoadingStarted.bind(this);
     this._loadingCompletedHandler = this._onLoadingCompleted.bind(this);
+    this._onResponseHandler = this._onResponse.bind(this);
     this._client.on('Network.requestWillBeSent', this._loadingStartedHandler);
     this._client.on('Network.loadingFinished', this._loadingCompletedHandler);
     this._client.on('Network.loadingFailed', this._loadingCompletedHandler);
     this._client.on('Network.webSocketCreated', this._loadingStartedHandler);
     this._client.on('Network.webSocketClosed', this._loadingCompletedHandler);
+    this._networkManager.on(NetworkManager.Events.Response, this._onResponseHandler);
 
     this._inflightRequests = 0;
     this._requestIds = new Set();
+    /** @type {!Map<string, !Response>} */
+    this._responses = new Map();
   }
 
   _cleanup() {
@@ -99,10 +108,19 @@ class Navigator {
     this._client.removeListener('Network.loadingFailed', this._loadingCompletedHandler);
     this._client.removeListener('Network.webSocketCreated', this._loadingStartedHandler);
     this._client.removeListener('Network.webSocketClosed', this._loadingCompletedHandler);
+    this._networkManager.removeListener(NetworkManager.Events.Response, this._onResponseHandler);
 
     clearTimeout(this._idleTimer);
     clearTimeout(this._maximumTimer);
+    this._responses = new Map();
+  }
+
+  /**
+   * @param {!Response} response
+   */
+  _onResponse(response) {
+    this._responses.set(response.url, response);
   }
 }
 
-module.exports = Navigator;
+module.exports = NavigatorWatcher;

lib/Page.js

@@ -18,7 +18,7 @@ let fs = require('fs');
 let EventEmitter = require('events');
 let mime = require('mime');
 let NetworkManager = require('./NetworkManager');
-let Navigator = require('./Navigator');
+let NavigatorWatcher = require('./NavigatorWatcher');
 let Dialog = require('./Dialog');
 let EmulationManager = require('./EmulationManager');
 let FrameManager = require('./FrameManager');
@@ -267,32 +267,36 @@ class Page extends EventEmitter {
    * @return {!Promise<!Response>}
    */
   async navigate(url, options) {
+    const watcher = new NavigatorWatcher(this._client, this._networkManager, options);
+    const result = watcher.waitForNavigation();
     const referrer = this._networkManager.httpHeaders()['referer'];
-    this._navigator = new Navigator(this._client, url, referrer, options);
-    return this.reload();
+    try {
+      await this._client.send('Page.navigate', {url, referrer});
+    } catch (e) {
+      watcher.cancel();
+      throw e;
+    }
+    const responses = await result;
+    return responses.get(this.mainFrame().url());
   }
 
   /**
-   * @return {!Promise<!Response>}
+   * @param {!Object=} options
+   * @return {!Promise<?Response>}
    */
-  async reload() {
-    if (!this._navigator)
-      return;
-    /** @type {!Map<string, !Response>} */
-    const responses = new Map();
-    const onResponse = response => responses.set(response.url, response);
-    this._networkManager.on(NetworkManager.Events.Response, onResponse);
-    try {
-      await this._navigator.navigate();
-    } finally {
-      this._networkManager.removeListener(NetworkManager.Events.Response, onResponse);
+  async reload(options) {
+    this._client.send('Page.reload');
+    return this.waitForNavigation(options);
   }
-    const response = responses.get(this.mainFrame().url());
-    console.assert(response);
 
-    // Await for a single raf rountrip to ensure basic rasterization is complete.
-    await this.evaluate(() => new Promise(fulfill => requestAnimationFrame(fulfill)));
-    return response;
+  /**
+   * @param {!Object=} options
+   * @return {!Promise<?Response>}
+   */
+  async waitForNavigation(options) {
+    const watcher = new NavigatorWatcher(this._client, this._networkManager, options);
+    const responses = await watcher.waitForNavigation();
+    return responses.get(this.mainFrame().url()) || null;
   }
 
   /**

test/test.js

@@ -427,6 +427,17 @@ describe('Puppeteer', function() {
     }));
   });
 
+  describe('Page.waitForNavigation', function() {
+    it('should work', SX(async function() {
+      await page.navigate(EMPTY_PAGE);
+      const result = page.waitForNavigation();
+      page.evaluate(url => window.location.href = url, PREFIX + '/grid.html');
+      const response = await result;
+      expect(response.ok).toBe(true);
+      expect(response.url).toContain('grid.html');
+    }));
+  });
+
   describe('Page.setInPageCallback', function() {
     it('should work', SX(async function() {
       await page.setInPageCallback('callController', function(a, b) {

utils/doclint/lint.js

@@ -11,7 +11,7 @@ let EXCLUDE_CLASSES = new Set([
   'EmulationManager',
   'FrameManager',
   'Helper',
-  'Navigator',
+  'NavigatorWatcher',
   'NetworkManager',
   'ProxyStream'
 ]);