1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
content / browser / preloading / prerenderer_impl.h [blame]
// Copyright 2022 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef CONTENT_BROWSER_PRELOADING_PRERENDERER_IMPL_H_
#define CONTENT_BROWSER_PRELOADING_PRERENDERER_IMPL_H_
#include <tuple>
#include "base/scoped_observation.h"
#include "content/browser/preloading/preloading_confidence.h"
#include "content/browser/preloading/prerender/prerender_host_registry.h"
#include "content/browser/preloading/prerenderer.h"
#include "content/public/browser/web_contents_observer.h"
namespace content {
class PrerenderHostRegistry;
class Page;
// Handles speculation-rules based prerenders.
class CONTENT_EXPORT PrerendererImpl : public Prerenderer,
WebContentsObserver,
PrerenderHostRegistry::Observer {
public:
explicit PrerendererImpl(RenderFrameHost& render_frame_host);
~PrerendererImpl() override;
// WebContentsObserver implementation:
void PrimaryPageChanged(Page& page) override;
void ProcessCandidatesForPrerender(
const std::vector<blink::mojom::SpeculationCandidatePtr>& candidates)
override;
bool MaybePrerender(const blink::mojom::SpeculationCandidatePtr& candidate,
const PreloadingPredictor& enacting_predictor,
PreloadingConfidence confidence) override;
void OnLCPPredicted() override;
bool ShouldWaitForPrerenderResult(const GURL& url) override;
// Sets a callback from PreloadingDecider to notify the cancellation of
// prerender to it.
void SetPrerenderCancellationCallback(
PrerenderCancellationCallback callback) override;
// PrerenderHostRegistry::Observer implementations:
void OnCancel(FrameTreeNodeId host_frame_tree_node_id,
const PrerenderCancellationReason& reason) override;
void OnRegistryDestroyed() override;
void CancelStartedPrerendersForTesting();
private:
struct PrerenderInfo;
void CancelStartedPrerenders();
// Used only for metric that counts received prerenders per
// primary page changed.
void RecordReceivedPrerendersCountToMetrics();
void ResetReceivedPrerendersCountForMetrics();
void IncrementReceivedPrerendersCountForMetrics(
PreloadingTriggerType trigger_type,
blink::mojom::SpeculationEagerness eagerness);
// Kept sorted by URL.
std::vector<PrerenderInfo> started_prerenders_;
// Used only for metric that counts received prerenders per
// primary page changed.
base::flat_map<PreloadingTriggerType,
std::array<int,
static_cast<size_t>(
blink::mojom::SpeculationEagerness::kMaxValue) +
1>>
received_prerenders_by_eagerness_;
// Used to notify cancellation from PrerendererImpl to PreloadingDecider.
// This is invoked in OnCancel, which is called when receiving a cancellation
// notification from PrerenderHostRegistry.
PrerenderCancellationCallback prerender_cancellation_callback_ =
base::DoNothing();
base::ScopedObservation<PrerenderHostRegistry,
PrerenderHostRegistry::Observer>
observation_{this};
base::WeakPtr<PrerenderHostRegistry> registry_;
// content::PreloadingDecider, which inherits content::DocumentUserData, owns
// `this`, so `this` can access `render_frame_host_` safely.
const raw_ref<RenderFrameHost> render_frame_host_;
// Below two fields are used to defer starting prerenders until LCP timing
// and are only used under LCPTimingPredictorPrerender2.
bool blocked_ = false;
using BlockedCandidateInfo =
std::tuple<blink::mojom::SpeculationCandidatePtr /*candidate*/,
PreloadingPredictor /*enacting_predictor*/,
PreloadingConfidence /*confidence*/>;
std::vector<BlockedCandidateInfo> blocked_candidates_;
};
} // namespace content
#endif // CONTENT_BROWSER_PRELOADING_PRERENDERER_IMPL_H_