Adds support for thumbnail click pings for Most Visited

chrome/browser/resources/local_ntp/most_visited_util.js

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 
 /**
  * @fileoverview Utilities for rendering most visited thumbnails and titles.
  */
 
 <include src="instant_iframe_validation.js">
@@ skipping 27 matching lines @@
   // (if it was provided), resulting in a grey tile.
   NTP_THUMBNAIL_ERROR: 6,
   // Used a gray tile with the domain as the fallback for a failed thumbnail.
   NTP_GRAY_TILE_FALLBACK: 7,
   // The visuals of that tile's fallback are handled externally.
   NTP_EXTERNAL_TILE_FALLBACK: 8,
   // The user moused over an NTP tile or title.
   NTP_MOUSEOVER: 9
 };
 
-
 /**
  * Type of the impression provider for a generic client-provided suggestion.
  * @type {string}
  * @const
  */
 var CLIENT_PROVIDER_NAME = 'client';
 
 /**
  * Type of the impression provider for a generic server-provided suggestion.
  * @type {string}
  * @const
  */
 var SERVER_PROVIDER_NAME = 'server';
 
 /**
+ * The origin of this request.
+ * @type {string}
+ * @const

[Mathieu, 2014/07/30 14:12:54]

You can simplify to @const {string}

[fserb, 2014/07/31 18:18:47]

Done.

+ */
+var DOMAIN_ORIGIN = '{{ORIGIN}}';
+
+/**
  * Parses query parameters from Location.
  * @param {string} location The URL to generate the CSS url for.
  * @return {Object} Dictionary containing name value pairs for URL.
  */
 function parseQueryParams(location) {
   var params = Object.create(null);
   var query = location.search.substring(1);
   var vars = query.split('&');
   for (var i = 0; i < vars.length; i++) {
     var pair = vars[i].split('=');
@@ skipping 40 matching lines @@
     link.textContent = text;
   link.addEventListener('mouseover', function() {
     var ntpApiHandle = chrome.embeddedSearch.newTabPage;
     ntpApiHandle.logEvent(NTP_LOGGING_EVENT_TYPE.NTP_MOUSEOVER);
   });
 
   // Webkit's security policy prevents some Most Visited thumbnails from
   // working (those with schemes different from http and https). Therefore,
   // navigateContentWindow is being used in order to get all schemes working.
   link.addEventListener('click', function handleNavigation(e) {
+    if (params.ping) {

[Mathieu, 2014/07/30 14:12:54]

nit: you can omit braces

[fserb, 2014/07/31 18:18:47]

Acknowledged.

+      generatePing(DOMAIN_ORIGIN + params.ping);
+    }
+
     var ntpApiHandle = chrome.embeddedSearch.newTabPage;
     if ('pos' in params && isFinite(params.pos)) {
       ntpApiHandle.logMostVisitedNavigation(parseInt(params.pos, 10),
                                             provider || '');
     }
     var isServerSuggestion = 'url' in params;
     if (!isServerSuggestion) {
       e.preventDefault();
       ntpApiHandle.navigateContentWindow(href, getDispositionFromEvent(e));
     }
     // Else follow <a> normally, so transition type would be LINK.

[Mathieu, 2014/07/30 14:12:54]

This comment seems to say that for server suggestions we use <a> tags for
navigation, so perhaps we can use the 'ping' there?

[fserb, 2014/07/31 18:18:47]

as discussed offline, trying not to rely on a ping for the future.

   });
 
   return link;
 }
 
 
 /**
  * Decodes most visited styles from URL parameters.
  * - f: font-family
  * - fs: font-size as a number in pixels.
@@ skipping 23 matching lines @@
   return styles;
 }
 
 
 /**
  * @param {string} location A location containing URL parameters.
  * @param {function(Object, Object)} fill A function called with styles and
  *     data to fill.
  */
 function fillMostVisited(location, fill) {
-  var params = parseQueryParams(document.location);
+  var params = parseQueryParams(location);
   params.rid = parseInt(params.rid, 10);
   if (!isFinite(params.rid) && !params.url)
     return;
   // Log whether the suggestion was obtained from the server or the client.
   chrome.embeddedSearch.newTabPage.logEvent(params.url ?
       NTP_LOGGING_EVENT_TYPE.NTP_SERVER_SIDE_SUGGESTION :
       NTP_LOGGING_EVENT_TYPE.NTP_CLIENT_SIDE_SUGGESTION);
   var data = {};
   if (params.url) {
     // Means that the suggestion data comes from the server. Create data object.
@@ skipping 16 matching lines @@
     data.provider = params.pr || CLIENT_PROVIDER_NAME;
   }
   if (/^javascript:/i.test(data.url) ||
       /^javascript:/i.test(data.thumbnailUrl) ||
       !/^[a-z0-9]{0,8}$/i.test(data.provider))
     return;
   if (data.direction)
     document.body.dir = data.direction;
   fill(params, data);
 }
+
+
+/**
+ * Sends a POST request to ping url.
+ * @param {string} url URL to be pinged.
+ */
+function generatePing(url) {
+  if (navigator.sendBeacon) {
+    navigator.sendBeacon(url);
+  } else {
+    // sendBeacon is still in experimental, so for now we use 'a ping'

[Mathieu, 2014/07/30 14:12:54]

you could say: "If sendBeacon is not enabled, use 'a ping'"

And mention that we use both in the CL description

[fserb, 2014/07/31 18:18:47]

Done.

+    var a = document.createElement('a');
+    a.href = '#';
+    a.ping = url;
+    a.click();
+  }
+}