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content / browser / preloading / prerender / prerender_commit_deferring_condition.cc [blame]
// Copyright 2021 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "content/browser/preloading/prerender/prerender_commit_deferring_condition.h"
#include "base/memory/ptr_util.h"
#include "base/task/sequenced_task_runner.h"
#include "content/browser/preloading/prerender/prerender_host.h"
#include "content/browser/preloading/prerender/prerender_metrics.h"
#include "content/browser/renderer_host/frame_tree.h"
#include "content/browser/renderer_host/frame_tree_node.h"
#include "content/browser/renderer_host/navigation_request.h"
#include "content/public/browser/render_frame_host.h"
namespace content {
namespace {
// Returns the root prerender frame tree node associated with navigation_request
// of ongoing prerender activation.
FrameTreeNode* GetRootPrerenderFrameTreeNode(
FrameTreeNodeId prerender_frame_tree_node_id) {
FrameTreeNode* root =
FrameTreeNode::GloballyFindByID(prerender_frame_tree_node_id);
if (root) {
CHECK(root->IsOutermostMainFrame());
}
return root;
}
} // namespace
// static
std::unique_ptr<CommitDeferringCondition>
PrerenderCommitDeferringCondition::MaybeCreate(
NavigationRequest& navigation_request,
NavigationType navigation_type,
std::optional<FrameTreeNodeId> candidate_prerender_frame_tree_node_id) {
// Don't create if this navigation is not for prerender page activation.
if (navigation_type != NavigationType::kPrerenderedPageActivation)
return nullptr;
return base::WrapUnique(new PrerenderCommitDeferringCondition(
navigation_request, candidate_prerender_frame_tree_node_id.value()));
}
PrerenderCommitDeferringCondition::~PrerenderCommitDeferringCondition() =
default;
PrerenderCommitDeferringCondition::PrerenderCommitDeferringCondition(
NavigationRequest& navigation_request,
FrameTreeNodeId candidate_prerender_frame_tree_node_id)
: CommitDeferringCondition(navigation_request),
WebContentsObserver(navigation_request.GetWebContents()),
candidate_prerender_frame_tree_node_id_(
candidate_prerender_frame_tree_node_id) {
CHECK(candidate_prerender_frame_tree_node_id_);
}
CommitDeferringCondition::Result
PrerenderCommitDeferringCondition::WillCommitNavigation(
base::OnceClosure resume) {
FrameTreeNode* prerender_frame_tree_node =
GetRootPrerenderFrameTreeNode(candidate_prerender_frame_tree_node_id_);
// If the prerender FrameTreeNode is gone, the prerender activation is allowed
// to continue here but will fail soon.
if (!prerender_frame_tree_node) {
return Result::kProceed;
}
PrerenderHost& prerender_host =
PrerenderHost::GetFromFrameTreeNode(*prerender_frame_tree_node);
// If there is no ongoing main frame navigation in prerender frame tree, the
// prerender activation is allowed to continue.
if (!prerender_frame_tree_node->HasNavigation()) {
// Record the defer waiting time for PrerenderCommitDeferringCondition as no
// delay.
RecordPrerenderActivationCommitDeferTime(
base::TimeDelta(), prerender_host.trigger_type(),
prerender_host.embedder_histogram_suffix());
return Result::kProceed;
}
// If we cannot match the navigation URL the prerender activation is allowed
// to continue here but will fail soon. This can happen when matching
// by No-Vary-Search hint and the No-Vary-Search header doesn't agree.
if (!prerender_host.IsUrlMatch(GetNavigationHandle().GetURL())) {
return Result::kProceed;
}
// Defer the prerender activation until the ongoing prerender main frame
// navigation commits.
done_closure_ = std::move(resume);
defer_start_time_ = base::TimeTicks::Now();
return Result::kDefer;
}
const char* PrerenderCommitDeferringCondition::TraceEventName() const {
return "PrerenderCommitDeferringCondition";
}
void PrerenderCommitDeferringCondition::DidFinishNavigation(
NavigationHandle* handle) {
auto* finished_navigation_request = NavigationRequest::From(handle);
FrameTreeNode* prerender_frame_tree_node =
GetRootPrerenderFrameTreeNode(candidate_prerender_frame_tree_node_id_);
// If the prerender frame tree node is gone, there is nothing to do.
if (!prerender_frame_tree_node)
return;
// If the finished navigation is not for the prerendering main frame,
// ignore this event.
if (finished_navigation_request->frame_tree_node() !=
prerender_frame_tree_node) {
return;
}
// PrerenderNavigationThrottle allows navigations after the initial commit so
// the callback should be called after all ongoing navigations are completed.
if (done_closure_ && !prerender_frame_tree_node->HasNavigation()) {
// It's possible that another navigation happens after posting a task to
// resume the activation because PrerenderNavigationThrottle allows the main
// frame navigation in a prerendered page. In that case, prerendering is
// cancelled and the activation falls back to network.
base::SequencedTaskRunner::GetCurrentDefault()->PostTask(
FROM_HERE, std::move(done_closure_));
// Record the defer waiting time for PrerenderCommitDeferringCondition.
base::TimeDelta delta = base::TimeTicks::Now() - defer_start_time_;
PrerenderHost& prerender_host =
PrerenderHost::GetFromFrameTreeNode(*prerender_frame_tree_node);
RecordPrerenderActivationCommitDeferTime(
delta, prerender_host.trigger_type(),
prerender_host.embedder_histogram_suffix());
}
}
} // namespace content