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/json/json_writer.h"
   8 #include "base/metrics/histogram.h"
   9 #include "base/metrics/statistics_recorder.h"
  10 #include "base/strings/string_util.h"
  11 #include "content/common/child_process_messages.h"
  12 #include "content/renderer/render_view_impl.h"
  13 #include "gin/handle.h"
  14 #include "gin/object_template_builder.h"
  15 #include "third_party/WebKit/public/web/WebFrame.h"
  16 #include "third_party/WebKit/public/web/WebKit.h"
  17 #include "third_party/WebKit/public/web/WebView.h"
  18
  19 namespace content {
  20
  21 namespace {
  22
  23 bool CurrentRenderViewImpl(RenderViewImpl** out) {
  24   blink::WebFrame* web_frame = blink::WebFrame::frameForCurrentContext();
  25   if (!web_frame)
  26     return false;
  27
  28   blink::WebView* web_view = web_frame->view();
  29   if (!web_view)
  30     return false;
  31
  32   RenderViewImpl* render_view_impl =
  33       RenderViewImpl::FromWebView(web_view);
  34   if (!render_view_impl)
  35     return false;
  36
  37   *out = render_view_impl;
  38   return true;
  39 }
  40
  41 // Encodes a WebContentsLoadTime as JSON.
  42 // Input:
  43 // - |load_start_time| - time at which page load started.
  44 // - |load_stop_time| - time at which page load stopped.
  45 // - |result| - returned JSON.
  46 // Example return value:
  47 // {'load_start_ms': 1, 'load_duration_ms': 2.5}
  48 // either value may be null if a web contents hasn't fully loaded.
  49 // load_start_ms is represented as milliseconds since system boot.
  50 void ConvertLoadTimeToJSON(
  51     const base::Time& load_start_time,
  52     const base::Time& load_stop_time,
  53     std::string *result) {
  54   base::DictionaryValue item;
  55
  56   if (load_start_time.is_null()) {
  57     item.Set("load_start_ms", base::Value::CreateNullValue());
  58   } else {
  59     item.SetDouble("load_start_ms", load_start_time.ToInternalValue() / 1000);
  60   }
  61   if (load_start_time.is_null() || load_stop_time.is_null()) {
  62     item.Set("load_duration_ms", base::Value::CreateNullValue());
  63   } else {
  64     item.SetDouble("load_duration_ms",
  65         (load_stop_time - load_start_time).InMillisecondsF());
  66   }
  67   base::JSONWriter::Write(&item, result);
  68 }
  69
  70 }  // namespace
  71
  72 // static
  73 gin::WrapperInfo StatsCollectionController::kWrapperInfo = {
  74     gin::kEmbedderNativeGin
  75 };
  76
  77 // static
  78 void StatsCollectionController::Install(blink::WebFrame* frame) {
  79   v8::Isolate* isolate = blink::mainThreadIsolate();
  80   v8::HandleScope handle_scope(isolate);
  81   v8::Handle<v8::Context> context = frame->mainWorldScriptContext();
  82   if (context.IsEmpty())
  83     return;
  84
  85   v8::Context::Scope context_scope(context);
  86
  87   gin::Handle<StatsCollectionController> controller =
  88       gin::CreateHandle(isolate, new StatsCollectionController());
  89   v8::Handle<v8::Object> global = context->Global();
  90   global->Set(gin::StringToV8(isolate, "statsCollectionController"),
  91               controller.ToV8());
  92 }
  93
  94 StatsCollectionController::StatsCollectionController() {}
  95
  96 StatsCollectionController::~StatsCollectionController() {}
  97
  98 gin::ObjectTemplateBuilder StatsCollectionController::GetObjectTemplateBuilder(
  99     v8::Isolate* isolate) {
 100   return gin::Wrappable<StatsCollectionController>::GetObjectTemplateBuilder(
 101       isolate)
 102       .SetMethod("getHistogram", &StatsCollectionController::GetHistogram)
 103       .SetMethod("getBrowserHistogram",
 104                  &StatsCollectionController::GetBrowserHistogram)
 105       .SetMethod("tabLoadTiming", &StatsCollectionController::GetTabLoadTiming);
 106 }
 107
 108 std::string StatsCollectionController::GetHistogram(
 109     const std::string& histogram_name) {
 110   base::HistogramBase* histogram =
 111       base::StatisticsRecorder::FindHistogram(histogram_name);
 112   std::string output;
 113   if (!histogram) {
 114     output = "{}";
 115   } else {
 116     histogram->WriteJSON(&output);
 117   }
 118   return output;
 119 }
 120
 121 std::string StatsCollectionController::GetBrowserHistogram(
 122     const std::string& histogram_name) {
 123   RenderViewImpl *render_view_impl = NULL;
 124   if (!CurrentRenderViewImpl(&render_view_impl)) {
 125     NOTREACHED();
 126     return std::string();
 127   }
 128
 129   std::string histogram_json;
 130   render_view_impl->Send(new ChildProcessHostMsg_GetBrowserHistogram(
 131       histogram_name, &histogram_json));
 132   return histogram_json;
 133 }
 134
 135 std::string StatsCollectionController::GetTabLoadTiming() {
 136   RenderViewImpl *render_view_impl = NULL;
 137   if (!CurrentRenderViewImpl(&render_view_impl)) {
 138     NOTREACHED();
 139     return std::string();
 140   }
 141
 142   StatsCollectionObserver* observer =
 143       render_view_impl->GetStatsCollectionObserver();
 144   if (!observer) {
 145     NOTREACHED();
 146     return std::string();
 147   }
 148
 149   std::string tab_timing_json;
 150   ConvertLoadTimeToJSON(
 151       observer->load_start_time(), observer->load_stop_time(),
 152       &tab_timing_json);
 153   return tab_timing_json;
 154 }
 155
 156 }  // namespace content