chrome/browser/resources/net_internals/bandwidth_view.js

   1 // Copyright (c) 2012 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 /** This view displays summary statistics on bandwidth usage. */
   6 var BandwidthView = (function() {
   7   'use strict';
   8
   9   // We inherit from DivView.
  10   var superClass = DivView;
  11
  12   /**
  13    * @constructor
  14    */
  15   function BandwidthView() {
  16     assertFirstConstructorCall(BandwidthView);
  17
  18     // Call superclass's constructor.
  19     superClass.call(this, BandwidthView.MAIN_BOX_ID);
  20
  21     g_browser.addSessionNetworkStatsObserver(this, true);
  22     g_browser.addHistoricNetworkStatsObserver(this, true);
  23
  24     this.sessionNetworkStats_ = null;
  25     this.historicNetworkStats_ = null;
  26   }
  27
  28   BandwidthView.TAB_ID = 'tab-handle-bandwidth';
  29   BandwidthView.TAB_NAME = 'Bandwidth';
  30   BandwidthView.TAB_HASH = '#bandwidth';
  31
  32   // IDs for special HTML elements in bandwidth_view.html
  33   BandwidthView.MAIN_BOX_ID = 'bandwidth-view-tab-content';
  34
  35   cr.addSingletonGetter(BandwidthView);
  36
  37   BandwidthView.prototype = {
  38     // Inherit the superclass's methods.
  39     __proto__: superClass.prototype,
  40
  41     onLoadLogFinish: function(data) {
  42       // Even though this information is included in log dumps, there's no real
  43       // reason to display it when debugging a loaded log file.
  44       return false;
  45     },
  46
  47     /**
  48      * Retains information on bandwidth usage this session.
  49      */
  50     onSessionNetworkStatsChanged: function(sessionNetworkStats) {
  51       this.sessionNetworkStats_ = sessionNetworkStats;
  52       return this.updateBandwidthUsageTable_();
  53     },
  54
  55     /**
  56      * Displays information on bandwidth usage this session and over the
  57      * browser's lifetime.
  58      */
  59     onHistoricNetworkStatsChanged: function(historicNetworkStats) {
  60       this.historicNetworkStats_ = historicNetworkStats;
  61       return this.updateBandwidthUsageTable_();
  62     },
  63
  64     /**
  65      * Update the bandwidth usage table.  Returns false on failure.
  66      */
  67     updateBandwidthUsageTable_: function() {
  68       var sessionNetworkStats = this.sessionNetworkStats_;
  69       var historicNetworkStats = this.historicNetworkStats_;
  70       if (!sessionNetworkStats || !historicNetworkStats)
  71         return false;
  72
  73       var sessionOriginal = sessionNetworkStats.session_original_content_length;
  74       var sessionReceived = sessionNetworkStats.session_received_content_length;
  75       var historicOriginal =
  76           historicNetworkStats.historic_original_content_length;
  77       var historicReceived =
  78           historicNetworkStats.historic_received_content_length;
  79
  80       var rows = [];
  81       rows.push({
  82           title: 'Original (KB)',
  83           sessionValue: bytesToRoundedKilobytes_(sessionOriginal),
  84           historicValue: bytesToRoundedKilobytes_(historicOriginal)
  85       });
  86       rows.push({
  87           title: 'Received (KB)',
  88           sessionValue: bytesToRoundedKilobytes_(sessionReceived),
  89           historicValue: bytesToRoundedKilobytes_(historicReceived)
  90       });
  91       rows.push({
  92           title: 'Savings (KB)',
  93           sessionValue:
  94               bytesToRoundedKilobytes_(sessionOriginal - sessionReceived),
  95           historicValue:
  96               bytesToRoundedKilobytes_(historicOriginal - historicReceived)
  97       });
  98       rows.push({
  99           title: 'Savings (%)',
 100           sessionValue: getPercentSavings_(sessionOriginal, sessionReceived),
 101           historicValue: getPercentSavings_(historicOriginal,
 102                                             historicReceived)
 103       });
 104
 105       var input = new JsEvalContext({rows: rows});
 106       jstProcess(input, $(BandwidthView.MAIN_BOX_ID));
 107       return true;
 108     }
 109   };
 110
 111   /**
 112    * Converts bytes to kilobytes rounded to one decimal place.
 113    */
 114   function bytesToRoundedKilobytes_(val) {
 115     return (val / 1024).toFixed(1);
 116   }
 117
 118   /**
 119    * Returns bandwidth savings as a percent rounded to one decimal place.
 120    */
 121   function getPercentSavings_(original, received) {
 122     if (original > 0) {
 123       return ((original - received) * 100 / original).toFixed(1);
 124     }
 125     return '0.0';
 126   }
 127
 128   return BandwidthView;
 129 })();