blob: a535e3202a4b3823ae702d83b05c737000ece4de [file] [log] [blame]
// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "net/url_request/url_request_throttler_manager.h"
#include "base/check_op.h"
#include "base/strings/string_util.h"
#include "net/base/url_util.h"
#include "net/log/net_log.h"
#include "net/log/net_log_event_type.h"
#include "net/log/net_log_source_type.h"
namespace net {
const unsigned int URLRequestThrottlerManager::kMaximumNumberOfEntries = 1500;
const unsigned int URLRequestThrottlerManager::kRequestsBetweenCollecting = 200;
URLRequestThrottlerManager::URLRequestThrottlerManager() {
url_id_replacements_.ClearPassword();
url_id_replacements_.ClearUsername();
url_id_replacements_.ClearQuery();
url_id_replacements_.ClearRef();
NetworkChangeNotifier::AddIPAddressObserver(this);
NetworkChangeNotifier::AddConnectionTypeObserver(this);
}
URLRequestThrottlerManager::~URLRequestThrottlerManager() {
DCHECK_CALLED_ON_VALID_THREAD(thread_checker_);
NetworkChangeNotifier::RemoveIPAddressObserver(this);
NetworkChangeNotifier::RemoveConnectionTypeObserver(this);
// Since the manager object might conceivably go away before the
// entries, detach the entries' back-pointer to the manager.
auto i = url_entries_.begin();
while (i != url_entries_.end()) {
if (i->second.get() != nullptr) {
i->second->DetachManager();
}
++i;
}
// Delete all entries.
url_entries_.clear();
}
scoped_refptr<URLRequestThrottlerEntryInterface>
URLRequestThrottlerManager::RegisterRequestUrl(const GURL &url) {
DCHECK_CALLED_ON_VALID_THREAD(thread_checker_);
// Normalize the url.
std::string url_id = GetIdFromUrl(url);
// Periodically garbage collect old entries.
GarbageCollectEntriesIfNecessary();
// Find the entry in the map or create a new NULL entry.
scoped_refptr<URLRequestThrottlerEntry>& entry = url_entries_[url_id];
// If the entry exists but could be garbage collected at this point, we
// start with a fresh entry so that we possibly back off a bit less
// aggressively (i.e. this resets the error count when the entry's URL
// hasn't been requested in long enough).
if (entry.get() && entry->IsEntryOutdated()) {
entry = nullptr;
}
// Create the entry if needed.
if (entry.get() == nullptr) {
entry = base::MakeRefCounted<URLRequestThrottlerEntry>(this, url_id);
// We only disable back-off throttling on an entry that we have
// just constructed. This is to allow unit tests to explicitly override
// the entry for localhost URLs.
if (IsLocalhost(url)) {
if (!logged_for_localhost_disabled_ && IsLocalhost(url)) {
logged_for_localhost_disabled_ = true;
net_log_.AddEventWithStringParams(
NetLogEventType::THROTTLING_DISABLED_FOR_HOST, "host", url.host());
}
// TODO(joi): Once sliding window is separate from back-off throttling,
// we can simply return a dummy implementation of
// URLRequestThrottlerEntryInterface here that never blocks anything.
entry->DisableBackoffThrottling();
}
}
return entry;
}
void URLRequestThrottlerManager::OverrideEntryForTests(
const GURL& url,
scoped_refptr<URLRequestThrottlerEntry> entry) {
// Normalize the url.
std::string url_id = GetIdFromUrl(url);
// Periodically garbage collect old entries.
GarbageCollectEntriesIfNecessary();
url_entries_[url_id] = std::move(entry);
}
void URLRequestThrottlerManager::EraseEntryForTests(const GURL& url) {
// Normalize the url.
std::string url_id = GetIdFromUrl(url);
url_entries_.erase(url_id);
}
void URLRequestThrottlerManager::set_net_log(NetLog* net_log) {
DCHECK(net_log);
net_log_ = NetLogWithSource::Make(
net_log, NetLogSourceType::EXPONENTIAL_BACKOFF_THROTTLING);
}
NetLog* URLRequestThrottlerManager::net_log() const {
return net_log_.net_log();
}
void URLRequestThrottlerManager::OnIPAddressChanged() {
OnNetworkChange();
}
void URLRequestThrottlerManager::OnConnectionTypeChanged(
NetworkChangeNotifier::ConnectionType type) {
OnNetworkChange();
}
std::string URLRequestThrottlerManager::GetIdFromUrl(const GURL& url) const {
if (!url.is_valid())
return url.possibly_invalid_spec();
GURL id = url.ReplaceComponents(url_id_replacements_);
return base::ToLowerASCII(id.spec());
}
void URLRequestThrottlerManager::GarbageCollectEntriesIfNecessary() {
requests_since_last_gc_++;
if (requests_since_last_gc_ < kRequestsBetweenCollecting)
return;
requests_since_last_gc_ = 0;
GarbageCollectEntries();
}
void URLRequestThrottlerManager::GarbageCollectEntries() {
auto i = url_entries_.begin();
while (i != url_entries_.end()) {
if ((i->second)->IsEntryOutdated()) {
url_entries_.erase(i++);
} else {
++i;
}
}
// In case something broke we want to make sure not to grow indefinitely.
while (url_entries_.size() > kMaximumNumberOfEntries) {
url_entries_.erase(url_entries_.begin());
}
}
void URLRequestThrottlerManager::OnNetworkChange() {
// Remove all entries. Any entries that in-flight requests have a reference
// to will live until those requests end, and these entries may be
// inconsistent with new entries for the same URLs, but since what we
// want is a clean slate for the new connection type, this is OK.
url_entries_.clear();
requests_since_last_gc_ = 0;
}
} // namespace net