src/content/renderer/stats_collection_controller.cc

   1 // Copyright 2013 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 #include "content/renderer/stats_collection_controller.h"
   6
   7 #include "base/bind.h"
   8 #include "base/bind_helpers.h"
   9 #include "base/json/json_writer.h"
  10 #include "base/metrics/histogram.h"
  11 #include "base/metrics/statistics_recorder.h"
  12 #include "base/strings/string_util.h"
  13 #include "content/common/child_process_messages.h"
  14 #include "content/renderer/render_view_impl.h"
  15 #include "third_party/WebKit/public/web/WebFrame.h"
  16 #include "third_party/WebKit/public/web/WebView.h"
  17
  18 using webkit_glue::CppArgumentList;
  19 using webkit_glue::CppVariant;
  20
  21 namespace content {
  22
  23 namespace {
  24
  25 bool CurrentRenderViewImpl(RenderViewImpl** out) {
  26   WebKit::WebFrame* web_frame = WebKit::WebFrame::frameForCurrentContext();
  27   if (!web_frame)
  28     return false;
  29
  30   WebKit::WebView* web_view = web_frame->view();
  31   if (!web_view)
  32     return false;
  33
  34   RenderViewImpl* render_view_impl =
  35       RenderViewImpl::FromWebView(web_view);
  36   if (!render_view_impl)
  37     return false;
  38
  39   *out = render_view_impl;
  40   return true;
  41 }
  42
  43 // Encodes a WebContentsLoadTime as JSON.
  44 // Input:
  45 // - |load_start_time| - time at which page load started.
  46 // - |load_stop_time| - time at which page load stopped.
  47 // - |result| - returned JSON.
  48 // Example return value:
  49 // {'load_start_ms': 1, 'load_duration_ms': 2.5}
  50 // either value may be null if a web contents hasn't fully loaded.
  51 // load_start_ms is represented as milliseconds since system boot.
  52 void ConvertLoadTimeToJSON(
  53     const base::TimeTicks& load_start_time,
  54     const base::TimeTicks& load_stop_time,
  55     std::string *result) {
  56   base::DictionaryValue item;
  57
  58   if (load_start_time.is_null()) {
  59      item.Set("load_start_ms", base::Value::CreateNullValue());
  60   } else {
  61     // This code relies on an implementation detail of TimeTicks::Now() - that
  62     // its return value happens to coincide with the system uptime value in
  63     // microseconds, on Win/Mac/iOS/Linux/ChromeOS and Android.  See comments
  64     // in base::SysInfo::Uptime().
  65     item.SetDouble("load_start_ms", load_start_time.ToInternalValue() / 1000);
  66   }
  67   if (load_start_time.is_null() || load_stop_time.is_null()) {
  68     item.Set("load_duration_ms", base::Value::CreateNullValue());
  69   } else {
  70     item.SetDouble("load_duration_ms",
  71         (load_stop_time - load_start_time).InMilliseconds());
  72   }
  73   base::JSONWriter::Write(&item, result);
  74 }
  75
  76 }  // namespace
  77
  78 StatsCollectionController::StatsCollectionController()
  79     : sender_(NULL) {
  80   BindCallback("getHistogram",
  81                base::Bind(&StatsCollectionController::GetHistogram,
  82                           base::Unretained(this)));
  83   BindCallback("getBrowserHistogram",
  84                base::Bind(&StatsCollectionController::GetBrowserHistogram,
  85                           base::Unretained(this)));
  86   BindCallback("tabLoadTiming",
  87                base::Bind(
  88                   &StatsCollectionController::GetTabLoadTiming,
  89                   base::Unretained(this)));
  90 }
  91
  92 void StatsCollectionController::GetHistogram(const CppArgumentList& args,
  93                                             CppVariant* result) {
  94   if (args.size() != 1) {
  95     result->SetNull();
  96     return;
  97   }
  98   base::HistogramBase* histogram =
  99       base::StatisticsRecorder::FindHistogram(args[0].ToString());
 100   std::string output;
 101   if (!histogram) {
 102     output = "{}";
 103   } else {
 104     histogram->WriteJSON(&output);
 105   }
 106   result->Set(output);
 107 }
 108
 109 void StatsCollectionController::GetBrowserHistogram(const CppArgumentList& args,
 110                                                    CppVariant* result) {
 111   if (args.size() != 1) {
 112     result->SetNull();
 113     return;
 114   }
 115
 116   if (!sender_) {
 117     NOTREACHED();
 118     result->SetNull();
 119     return;
 120   }
 121
 122   std::string histogram_json;
 123   sender_->Send(new ChildProcessHostMsg_GetBrowserHistogram(
 124       args[0].ToString(), &histogram_json));
 125   result->Set(histogram_json);
 126 }
 127
 128 void StatsCollectionController::GetTabLoadTiming(
 129     const CppArgumentList& args,
 130     CppVariant* result) {
 131   if (!sender_) {
 132     NOTREACHED();
 133     result->SetNull();
 134     return;
 135   }
 136
 137   RenderViewImpl *render_view_impl = NULL;
 138   if (!CurrentRenderViewImpl(&render_view_impl)) {
 139     NOTREACHED();
 140     result->SetNull();
 141     return;
 142   }
 143
 144   StatsCollectionObserver* observer =
 145       render_view_impl->GetStatsCollectionObserver();
 146   if (!observer) {
 147     NOTREACHED();
 148     result->SetNull();
 149     return;
 150   }
 151
 152   std::string tab_timing_json;
 153   ConvertLoadTimeToJSON(
 154       observer->load_start_time(), observer->load_stop_time(),
 155       &tab_timing_json);
 156   result->Set(tab_timing_json);
 157 }
 158
 159 }  // namespace content