Report frequency of single page app navigations to UMA

third_party/WebKit/Source/core/loader/FrameLoader.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights
  * reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved.
  * (http://www.torchmobile.com/)
  * Copyright (C) 2008 Alp Toker <alp@atoker.com>
  * Copyright (C) Research In Motion Limited 2009. All rights reserved.
  * Copyright (C) 2011 Kris Jordan <krisjordan@gmail.com>
  * Copyright (C) 2011 Google Inc. All rights reserved.
@@ skipping 61 matching lines @@
 #include "core/loader/ProgressTracker.h"
 #include "core/loader/appcache/ApplicationCacheHost.h"
 #include "core/page/ChromeClient.h"
 #include "core/page/CreateWindow.h"
 #include "core/page/FrameTree.h"
 #include "core/page/Page.h"
 #include "core/page/scrolling/ScrollingCoordinator.h"
 #include "core/probe/CoreProbes.h"
 #include "core/svg/graphics/SVGImage.h"
 #include "core/xml/parser/XMLDocumentParser.h"
+#include "platform/Histogram.h"
 #include "platform/InstanceCounters.h"
 #include "platform/PluginScriptForbiddenScope.h"
 #include "platform/ScriptForbiddenScope.h"
 #include "platform/bindings/DOMWrapperWorld.h"
 #include "platform/instrumentation/tracing/TraceEvent.h"
 #include "platform/loader/fetch/ResourceFetcher.h"
 #include "platform/loader/fetch/ResourceRequest.h"
 #include "platform/network/HTTPParsers.h"
 #include "platform/network/NetworkUtils.h"
 #include "platform/scroll/ScrollAnimatorBase.h"
@@ skipping 385 matching lines @@
   return allowed;
 }
 
 void FrameLoader::UpdateForSameDocumentNavigation(
     const KURL& new_url,
     SameDocumentNavigationSource same_document_navigation_source,
     PassRefPtr<SerializedScriptValue> data,
     HistoryScrollRestorationType scroll_restoration_type,
     FrameLoadType type,
     Document* initiating_document) {
+  // This enum is used to index different kinds of single-page-application

[Nate Chapin, 2017/06/21 18:05:24]

Could we put this all of this logging in a helper? It seems like it's
complicated enough it deserves its own function.

[Liquan (Max) Gu, 2017/06/26 14:52:21]

By 'all of this logging' do you mean the big switch and
UMA_HISTOGRAM_ENUMERATION()? It looks weird to me to mix the logging logic and
categorizing logic in a helper function. Helper function with only categorizing
logic seems more normal? Let's say, a single_page_application_helper class with
FindSinglePageAppNavigationType()?

+  // navigations for UMA enum histogram. New enum values can be added, but
+  // existing enums must never be renumbered or deleted and reused.
+  // This enum should be consistent with SinglePageAppNavigationType in
+  // tools/metrics/histograms/enums.
+  //
+  // |SinglePageAppNavigationType| falls into this grid according to different
+  // combinations of |FrameLoadType| and |SameDocumentNavigationSource|:
+  //
+  //                              HistoryApi    Default
+  //  kFrameLoadTypeBackForward    illegal         1
+  // !kFrameLoadTypeBackForward       0            2
+  enum SinglePageAppNavigationType {

[tdresser, 2017/06/21 14:45:00]

We'd normally define the enum outside of this method. This would let you refer
to the enum values in the test for example, which will make the test a bit
clearer.

[Liquan (Max) Gu, 2017/06/26 14:52:21]

Good idea.

+    kSPANavTypeHistoryPushStateOrReplaceState = 0,
+    kSPANavTypeSameDocumentBackwardOrForward = 1,
+    kSPANavTypeOtherFragmentNavigation = 2,
+    kSPANavTypeCount
+  };
+  SinglePageAppNavigationType single_page_app_navigation_type;
+  switch (same_document_navigation_source) {
+    case kSameDocumentNavigationDefault:
+      if (type == kFrameLoadTypeBackForward) {
+        single_page_app_navigation_type =
+            kSPANavTypeSameDocumentBackwardOrForward;
+      } else {
+        single_page_app_navigation_type = kSPANavTypeOtherFragmentNavigation;
+      }
+      break;
+    case kSameDocumentNavigationHistoryApi:
+      // It's illegal to have both kSameDocumentNavigationHistoryApi and
+      // kFrameLoadTypeBackForward.
+      DCHECK(type != kFrameLoadTypeBackForward);
+      single_page_app_navigation_type =
+          kSPANavTypeHistoryPushStateOrReplaceState;
+  }
+  UMA_HISTOGRAM_ENUMERATION(
+      "RendererScheduler.UpdateForSameDocumentNavigationCount",
+      single_page_app_navigation_type, kSPANavTypeCount);
+
   TRACE_EVENT1("blink", "FrameLoader::updateForSameDocumentNavigation", "url",
                new_url.GetString().Ascii().data());
 
   // Generate start and stop notifications only when loader is completed so that
   // we don't fire them for fragment redirection that happens in window.onload
   // handler. See https://bugs.webkit.org/show_bug.cgi?id=31838
   // Do not fire the notifications if the frame is concurrently navigating away
   // from the document, since a new document is already loading.
   if (frame_->GetDocument()->LoadEventFinished() &&
       !provisional_document_loader_)
@@ skipping 1187 matching lines @@
   // TODO(japhet): This is needed because the browser process DCHECKs if the
   // first entry we commit in a new frame has replacement set. It's unclear
   // whether the DCHECK is right, investigate removing this special case.
   bool replace_current_item = load_type == kFrameLoadTypeReplaceCurrentItem &&
                               (!Opener() || !request.Url().IsEmpty());
   loader->SetReplacesCurrentHistoryItem(replace_current_item);
   return loader;
 }
 
 }  // namespace blink