PageLoadMetrics renderer and browser implementation (deprecated)

components/page_load_metrics/renderer/page_load_metrics_render_frame_observer.cc

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/time/time.h"
+#include "components/page_load_metrics/common/page_load_metrics_messages.h"
+#include "components/page_load_metrics/renderer/page_load_metrics_render_frame_observer.h"
+#include "content/public/renderer/render_frame.h"
+#include "third_party/WebKit/public/platform/WebURLResponse.h"
+#include "third_party/WebKit/public/web/WebDataSource.h"
+#include "third_party/WebKit/public/web/WebDocument.h"
+#include "third_party/WebKit/public/web/WebLocalFrame.h"
+#include "third_party/WebKit/public/web/WebPerformance.h"
+#include "url/gurl.h"
+
+using base::Time;
+
+namespace page_load_metrics {
+
+namespace {
+
+// PerformanceTiming is the concrete implementation of the Timing interface
+// that gets its timing data from a blink::WebPerformance instance.
+class PerformanceTiming : public PageLoadMetricsRenderFrameObserver::Timing {
+ public:
+  explicit PerformanceTiming(const blink::WebPerformance& performance)
+      : performance_(performance) {}
+
+  Time GetNavigationStart() const override {
+    return Time::FromDoubleT(performance_.navigationStart());
+  }
+
+  Time GetDOMContentLoadedEvent() const override {
+    return Time::FromDoubleT(performance_.domContentLoadedEventStart());
+  }
+
+  Time GetLoadEvent() const override {
+    return Time::FromDoubleT(performance_.loadEventStart());
+  }
+
+  Time GetFirstLayout() const override {
+    return Time::FromDoubleT(performance_.firstLayout());
+  }
+
+ private:
+  blink::WebPerformance performance_;
+
+  DISALLOW_COPY_AND_ASSIGN(PerformanceTiming);
+};
+
+}  // namespace
+
+// PageMetricsSender is a helper class responsible for sending page load
+// metrics over the lifetime of a webpage. A PageMetricsSender instance is
+// active from the time a provisional load is committed, until the time the
+// provisional load for the next page is started.
+class PageLoadMetricsRenderFrameObserver::PageMetricsSender {
+ public:
+  explicit PageMetricsSender(PageLoadMetricsRenderFrameObserver* parent);
+  void MaybeSendMetrics(const Timing& timing);
+
+ private:
+  void Send(IPC::Message* message) { parent_->Send(message); }
+  int routing_id() const { return parent_->routing_id(); }
+
+  void MaybeSendFirstLayout(const Timing& timing);
+  void MaybeSendDOMContentLoadedEvent(const Timing& timing);
+  void MaybeSendLoadEvent(const Timing& timing);
+
+  PageLoadMetricsRenderFrameObserver* const parent_;

[nasko, 2015/08/20 00:22:18]

Parent has a very well defined meaning with frames - it is the parent frame. It
is confusing to see parent here refer to an outer class that initializes this
one.

[Bryan McQuade, 2015/08/25 13:53:36]

This got refactored so we no longer have a parent_ pointer.

+  bool did_send_first_layout_;
+  bool did_send_dom_content_loaded_event_;
+  bool did_send_load_event_;
+};
+
+PageLoadMetricsRenderFrameObserver::PageLoadMetricsRenderFrameObserver(
+    content::RenderFrame* render_frame)
+    : content::RenderFrameObserver(render_frame) {}
+
+PageLoadMetricsRenderFrameObserver::~PageLoadMetricsRenderFrameObserver() {}
+
+// TODO(bmcquade): use DidChangePerformanceTiming instead, once available.
+void PageLoadMetricsRenderFrameObserver::DidFinishDocumentLoad() {
+  MaybeSendMetrics();
+}
+
+// TODO(bmcquade): use DidChangePerformanceTiming instead, once available.
+void PageLoadMetricsRenderFrameObserver::DidFinishLoad() {
+  MaybeSendMetrics();
+}
+
+void PageLoadMetricsRenderFrameObserver::DidStartProvisionalLoad() {
+  // A provisional page load has started. Shut down metrics reporting until the
+  // next page load is committed. Note that a provisoinal load may fail. We
+  // simply stop reporting metrics in that case, until the next successful page
+  // load is committed.
+  page_metrics_sender_.reset();
+}
+
+void PageLoadMetricsRenderFrameObserver::DidCommitProvisionalLoad(
+    bool is_new_navigation, bool is_same_page_navigation) {
+  // Same-page navigations (e.g. an in-document navigation from a fragment
+  // link) aren't full page loads, since they don't go to network to load the
+  // main HTML resource. DidStartProvisionalLoad doesn't get invoked for same

[nasko, 2015/08/20 00:22:18]

Do we only care about network loads? If so, we need to avoid data: and blob:
URLs as well.

[Bryan McQuade, 2015/08/25 13:53:36]

Ah, interesting. Are you saying that DidStartProvisionalLoad doesn't get invoked
for data: and blob: URLs?

+  // page navigations, so we may still have an active page_metrics_sender_ at
+  // this point.
+  if (is_same_page_navigation)
+    return;
+
+  DCHECK(!page_metrics_sender_);
+
+  // We only create a PageMetricsSender if the page meets the criteria for
+  // sending and recording metrics. Once page_metrics_sender_ is non-null,
+  // we will send metrics for the current page at some later time, as those
+  // metrics become available.
+  if (ShouldSendMetrics())
+    page_metrics_sender_.reset(new PageMetricsSender(this));
+}
+
+void PageLoadMetricsRenderFrameObserver::MaybeSendMetrics() {
+  if (!page_metrics_sender_)
+    return;
+
+  scoped_ptr<Timing> timing(CreateTiming());
+  page_metrics_sender_->MaybeSendMetrics(*timing);
+}
+
+bool PageLoadMetricsRenderFrameObserver::ShouldSendMetrics() const {
+  const blink::WebLocalFrame& frame = *render_frame()->GetWebFrame();
+  // We only generate historgrams for main frames.
+  if (frame.parent())
+    return false;
+
+  const blink::WebDocument& document = frame.document();
+  // Ignore non-HTTP schemes (e.g. chrome://).
+  const GURL& url = document.url();
+  if (!url.SchemeIsHTTPOrHTTPS())
+    return false;
+
+  const blink::WebURLResponse& url_response = frame.dataSource()->response();
+  // Ignore multipart responses (e.g. MHTML).
+  if (url_response.isMultipartPayload())
+    return false;
+
+  // Ignore non-HTML documents (e.g. SVG). Note that images are treated by
+  // Blink as HTML documents, so to exclude images, we must perform
+  // additional mime type checking below.
+  if (!document.isHTMLDocument() && !document.isXHTMLDocument())
+    return false;
+
+  // Ignore non-HTML mime types (e.g. images).
+  std::string mime_type = url_response.mimeType().utf8();
+  if (mime_type != "text/html" && mime_type != "application/xhtml+xml")
+    return false;
+
+  return true;
+}
+
+scoped_ptr<PageLoadMetricsRenderFrameObserver::Timing>
+PageLoadMetricsRenderFrameObserver::CreateTiming() {
+  blink::WebLocalFrame* frame = render_frame()->GetWebFrame();
+  scoped_ptr<Timing> timing(new PerformanceTiming(
+      frame ? frame->performance() : blink::WebPerformance()));
+  return timing.Pass();
+}
+
+PageLoadMetricsRenderFrameObserver::PageMetricsSender::PageMetricsSender(
+    PageLoadMetricsRenderFrameObserver* parent)
+    : parent_(parent),
+      did_send_first_layout_(false),
+      did_send_dom_content_loaded_event_(false),
+      did_send_load_event_(false) {}
+
+void PageLoadMetricsRenderFrameObserver::PageMetricsSender::MaybeSendMetrics(
+    const Timing& timing) {
+  MaybeSendFirstLayout(timing);
+  MaybeSendDOMContentLoadedEvent(timing);
+  MaybeSendLoadEvent(timing);
+}
+
+void PageLoadMetricsRenderFrameObserver::PageMetricsSender::
+    MaybeSendFirstLayout(const Timing& timing) {
+  if (did_send_first_layout_)
+    return;
+
+  if (timing.GetNavigationStart().is_null() ||
+      timing.GetFirstLayout().is_null())
+    return;
+
+  Send(new PageLoadMetricsMsg_FirstLayout(
+      routing_id(),
+      timing.GetFirstLayout() - timing.GetNavigationStart()));
+  did_send_first_layout_ = true;
+}
+
+void PageLoadMetricsRenderFrameObserver::PageMetricsSender::
+    MaybeSendDOMContentLoadedEvent(const Timing& timing) {
+  if (did_send_dom_content_loaded_event_)
+    return;
+
+  if (timing.GetNavigationStart().is_null() ||
+      timing.GetDOMContentLoadedEvent().is_null())
+    return;
+
+  Send(new PageLoadMetricsMsg_DOMContentLoadedEvent(
+      routing_id(),
+      timing.GetDOMContentLoadedEvent() - timing.GetNavigationStart()));
+  did_send_dom_content_loaded_event_ = true;
+}
+
+void PageLoadMetricsRenderFrameObserver::PageMetricsSender::MaybeSendLoadEvent(
+    const Timing& timing) {
+  if (did_send_load_event_)
+    return;
+
+  if (timing.GetNavigationStart().is_null() || timing.GetLoadEvent().is_null())
+    return;
+
+  Send(new PageLoadMetricsMsg_LoadEvent(
+      routing_id(),
+      timing.GetLoadEvent() - timing.GetNavigationStart()));
+  did_send_load_event_ = true;
+}
+
+}  // namespace page_load_metrics