chrome/browser/resources/predictors/resource_prefetch_predictor.js

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 /**
   6  * Requests the database from the backend.
   7  */
   8 function requestResourcePrefetchPredictorDb() {
   9   chrome.send('requestResourcePrefetchPredictorDb');
  10 }
  11
  12 /**
  13  * Callback from backend with the database contents. Sets up some globals and
  14  * calls to create the UI.
  15  * @param {Dictionary} database Information about ResourcePrefetchPredictor
  16  *     including the database as a flattened list, a boolean indicating if the
  17  *     system is enabled.
  18  */
  19 function updateResourcePrefetchPredictorDb(database) {
  20   updateResourcePrefetchPredictorDbView(database);
  21 }
  22
  23 /**
  24  * Truncates the string to keep the database readable.
  25  * @param {string} str The string to truncate.
  26  * @return {string} The truncated string.
  27  */
  28 function truncateString(str) {
  29   return str.length < 100 ? str : str.substring(0, 99);
  30 }
  31
  32 /**
  33  * Updates the table from the database.
  34  * @param {Dictionary} database Information about ResourcePrefetchPredictor
  35  *     including the database as a flattened list, a boolean indicating if the
  36  *     system is enabled and the current hit weight.
  37  */
  38 function updateResourcePrefetchPredictorDbView(database) {
  39   if (!database.enabled) {
  40     $('rpp_enabled').style.display = 'none';
  41     $('rpp_disabled').style.display = 'block';
  42     return;
  43   } else {
  44     $('rpp_enabled').style.display = 'block';
  45     $('rpp_disabled').style.display = 'none';
  46   }
  47
  48   var hasUrlData = database.url_db && database.url_db.length > 0;
  49   var hasHostData = database.host_db && database.host_db.length > 0;
  50
  51   if (hasUrlData)
  52     renderCacheData($('rpp_url_body'), database.url_db);
  53   if (hasHostData)
  54     renderCacheData($('rpp_host_body'), database.host_db);
  55 }
  56
  57 /**
  58  * Renders cache data for URL or host based data.
  59  * @param {HTMLElement} body element of table to render into.
  60  * @param {Dictionary} database to render.
  61  */
  62 function renderCacheData(body, database) {
  63   body.textContent = '';
  64   for (var i = 0; i < database.length; ++i) {
  65     var main = database[i];
  66
  67     for (var j = 0; j < main.resources.length; ++j) {
  68       var resource = main.resources[j];
  69       var row = document.createElement('tr');
  70
  71       if (j == 0) {
  72         var t = document.createElement('td');
  73         t.rowSpan = main.resources.length;
  74         t.textContent = truncateString(main.main_frame_url);
  75         t.className = 'last';
  76         row.appendChild(t);
  77       }
  78
  79       if (j == main.resources.length - 1)
  80         row.className = 'last';
  81
  82       row.appendChild(document.createElement('td')).textContent =
  83           truncateString(resource.resource_url);
  84       row.appendChild(document.createElement('td')).textContent =
  85           resource.resource_type;
  86       row.appendChild(document.createElement('td')).textContent =
  87           resource.number_of_hits;
  88       row.appendChild(document.createElement('td')).textContent =
  89           resource.number_of_misses;
  90       row.appendChild(document.createElement('td')).textContent =
  91           resource.consecutive_misses;
  92       row.appendChild(document.createElement('td')).textContent =
  93           resource.position;
  94       row.appendChild(document.createElement('td')).textContent =
  95           resource.score;
  96       body.appendChild(row);
  97     }
  98   }
  99 }
 100
 101 document.addEventListener('DOMContentLoaded',
 102                           requestResourcePrefetchPredictorDb);