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content / browser / preloading / prefetch / prefetch_params.cc [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.
#include "content/browser/preloading/prefetch/prefetch_params.h"
#include <string>
#include "base/command_line.h"
#include "base/metrics/field_trial_params.h"
#include "base/no_destructor.h"
#include "base/rand_util.h"
#include "content/browser/preloading/prefetch/prefetch_features.h"
#include "content/browser/preloading/preloading_trigger_type_impl.h"
#include "content/browser/preloading/prerender/prerender_features.h"
#include "content/common/features.h"
#include "content/public/browser/prefetch_service_delegate.h"
#include "content/public/common/content_features.h"
#include "third_party/blink/public/mojom/speculation_rules/speculation_rules.mojom.h"
namespace content {
GURL PrefetchProxyHost(const GURL& default_proxy_url) {
// Command line overrides take priority.
std::string cmd_line_value =
base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
"isolated-prerender-tunnel-proxy");
if (!cmd_line_value.empty()) {
GURL cmd_line_url(cmd_line_value);
if (cmd_line_url.is_valid()) {
return cmd_line_url;
}
LOG(ERROR) << "--isolated-prerender-tunnel-proxy value is invalid";
}
return default_proxy_url;
}
std::string PrefetchProxyServerExperimentGroup() {
return base::GetFieldTrialParamValueByFeature(
features::kPrefetchUseContentRefactor, "server_experiment_group");
}
bool PrefetchAllowAllDomains() {
return base::GetFieldTrialParamByFeatureAsBool(
features::kPrefetchUseContentRefactor, "allow_all_domains",
false) ||
base::CommandLine::ForCurrentProcess()->HasSwitch(
"isolated-prerender-allow-all-domains");
}
bool PrefetchAllowAllDomainsForExtendedPreloading() {
return base::GetFieldTrialParamByFeatureAsBool(
features::kPrefetchUseContentRefactor,
"allow_all_domains_for_extended_preloading", true);
}
bool PrefetchServiceSendDecoyRequestForIneligblePrefetch(
bool disabled_based_on_user_settings) {
if (base::CommandLine::ForCurrentProcess()->HasSwitch(
"prefetch-proxy-never-send-decoy-requests-for-testing")) {
return false;
}
if (base::CommandLine::ForCurrentProcess()->HasSwitch(
"prefetch-proxy-always-send-decoy-requests-for-testing")) {
return true;
}
if (base::GetFieldTrialParamByFeatureAsBool(
features::kPrefetchUseContentRefactor,
"disable_decoys_based_on_user_settings", true) &&
disabled_based_on_user_settings) {
return false;
}
double probability = base::GetFieldTrialParamByFeatureAsDouble(
features::kPrefetchUseContentRefactor,
"ineligible_decoy_request_probability", 1.0);
// Clamp to [0.0, 1.0].
probability = std::max(0.0, probability);
probability = std::min(1.0, probability);
// RandDouble returns [0.0, 1.0) so don't use <= here since that may return
// true when the probability is supposed to be 0 (i.e.: always false).
return base::RandDouble() < probability;
}
base::TimeDelta PrefetchTimeoutDuration() {
return base::Milliseconds(base::GetFieldTrialParamByFeatureAsInt(
features::kPrefetchUseContentRefactor, "prefetch_timeout_ms",
10 * 1000 /* 10 seconds */));
}
size_t PrefetchMainframeBodyLengthLimit() {
return 1024 * base::GetFieldTrialParamByFeatureAsInt(
features::kPrefetchUseContentRefactor,
"max_mainframe_body_length_kb", 5 * 1024);
}
bool PrefetchCloseIdleSockets() {
return base::GetFieldTrialParamByFeatureAsBool(
features::kPrefetchUseContentRefactor, "close_idle_sockets", true);
}
bool PrefetchStartsSpareRenderer() {
return base::CommandLine::ForCurrentProcess()->HasSwitch(
"isolated-prerender-start-spare-renderer") ||
base::GetFieldTrialParamByFeatureAsBool(
features::kPrefetchUseContentRefactor, "start_spare_renderer",
true);
}
base::TimeDelta PrefetchContainerLifetimeInPrefetchService() {
// A value of 0 or less, indicates that |PrefetchService| should keep the
// prefetch forever.
return base::Seconds(base::GetFieldTrialParamByFeatureAsInt(
features::kPrefetchUseContentRefactor, "prefetch_container_lifetime_s",
10 * 60 /* 10 minutes */));
}
bool PrefetchServiceHTMLOnly() {
return base::GetFieldTrialParamByFeatureAsBool(
features::kPrefetchUseContentRefactor, "html_only", false);
}
bool ShouldPrefetchBypassProxyForTestHost(std::string_view host) {
static const base::NoDestructor<std::string> bypass(
base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
"bypass-prefetch-proxy-for-host"));
if (bypass->empty()) {
return false;
}
return host == *bypass;
}
base::TimeDelta PrefetchCacheableDuration() {
return base::Seconds(base::GetFieldTrialParamByFeatureAsInt(
features::kPrefetchUseContentRefactor, "cacheable_duration", 300));
}
bool PrefetchProbingEnabled() {
return base::GetFieldTrialParamByFeatureAsBool(
features::kPrefetchUseContentRefactor, "must_probe_origin", true);
}
bool PrefetchCanaryCheckEnabled() {
return base::GetFieldTrialParamByFeatureAsBool(
features::kPrefetchUseContentRefactor, "do_canary", true);
}
bool PrefetchTLSCanaryCheckEnabled() {
return base::GetFieldTrialParamByFeatureAsBool(
features::kPrefetchUseContentRefactor, "do_tls_canary", false);
}
GURL PrefetchTLSCanaryCheckURL(const GURL& default_tls_canary_check_url) {
GURL url(base::GetFieldTrialParamValueByFeature(
features::kPrefetchUseContentRefactor, "tls_canary_url"));
if (url.is_valid())
return url;
return default_tls_canary_check_url;
}
GURL PrefetchDNSCanaryCheckURL(const GURL& default_dns_canary_check_url) {
GURL url(base::GetFieldTrialParamValueByFeature(
features::kPrefetchUseContentRefactor, "dns_canary_url"));
if (url.is_valid())
return url;
return default_dns_canary_check_url;
}
base::TimeDelta PrefetchCanaryCheckCacheLifetime() {
return base::Hours(base::GetFieldTrialParamByFeatureAsInt(
features::kPrefetchUseContentRefactor, "canary_cache_hours", 24));
}
base::TimeDelta PrefetchCanaryCheckTimeout() {
return base::Milliseconds(base::GetFieldTrialParamByFeatureAsInt(
features::kPrefetchUseContentRefactor, "canary_check_timeout_ms",
5 * 1000 /* 5 seconds */));
}
int PrefetchCanaryCheckRetries() {
return base::GetFieldTrialParamByFeatureAsInt(
features::kPrefetchUseContentRefactor, "canary_check_retries", 1);
}
base::TimeDelta PrefetchBlockUntilHeadTimeout(
const PrefetchType& prefetch_type) {
int timeout_in_milliseconds = 0;
if (IsSpeculationRuleType(prefetch_type.trigger_type())) {
switch (prefetch_type.GetEagerness()) {
case blink::mojom::SpeculationEagerness::kEager:
timeout_in_milliseconds = base::GetFieldTrialParamByFeatureAsInt(
features::kPrefetchUseContentRefactor,
"block_until_head_timeout_eager_prefetch", 1000);
break;
case blink::mojom::SpeculationEagerness::kModerate:
timeout_in_milliseconds = base::GetFieldTrialParamByFeatureAsInt(
features::kPrefetchUseContentRefactor,
"block_until_head_timeout_moderate_prefetch", 0);
break;
case blink::mojom::SpeculationEagerness::kConservative:
timeout_in_milliseconds = base::GetFieldTrialParamByFeatureAsInt(
features::kPrefetchUseContentRefactor,
"block_until_head_timeout_conservative_prefetch", 0);
break;
}
} else {
timeout_in_milliseconds = base::GetFieldTrialParamByFeatureAsInt(
features::kPrefetchUseContentRefactor,
"block_until_head_timeout_embedder_prefetch", 1000);
}
return base::Milliseconds(timeout_in_milliseconds);
}
std::string GetPrefetchEagernessHistogramSuffix(
blink::mojom::SpeculationEagerness eagerness) {
switch (eagerness) {
case blink::mojom::SpeculationEagerness::kEager:
return "Eager";
case blink::mojom::SpeculationEagerness::kModerate:
return "Moderate";
case blink::mojom::SpeculationEagerness::kConservative:
return "Conservative";
}
}
size_t MaxNumberOfEagerPrefetchesPerPage() {
int max = base::GetFieldTrialParamByFeatureAsInt(features::kPrefetchNewLimits,
"max_eager_prefetches", 50);
return std::max(0, max);
}
size_t MaxNumberOfNonEagerPrefetchesPerPage() {
int max = base::GetFieldTrialParamByFeatureAsInt(
features::kPrefetchNewLimits, "max_non_eager_prefetches", 2);
return std::max(0, max);
}
bool PrefetchNIKScopeEnabled() {
return base::FeatureList::IsEnabled(features::kPrefetchNIKScope);
}
bool PrefetchBrowserInitiatedTriggersEnabled() {
return base::FeatureList::IsEnabled(
features::kPrefetchBrowserInitiatedTriggers);
}
bool UseNewWaitLoop() {
return base::FeatureList::IsEnabled(features::kPrefetchNewWaitLoop) ||
(base::FeatureList::IsEnabled(features::kPrefetchReusable) &&
features::kPrefetchReusableUseNewWaitLoop.Get()) ||
base::FeatureList::IsEnabled(
features::kPrerender2FallbackPrefetchSpecRules);
}
} // namespace content