blob: 86ac1258bdad81ba4215b9d86b27f9efdaf3aac8 [file] [log] [blame]
// Copyright (c) 2012 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 <map>
#include <memory>
#include <string>
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/synchronization/lock.h"
#include "extensions/renderer/extension_throttle_entry.h"
#include "url/gurl.h"
namespace blink {
class WebURLRequest;
} // namespace blink
namespace content {
class URLLoaderThrottle;
} // namespace content
namespace net {
struct RedirectInfo;
} // namespace net
namespace network {
struct ResourceResponseHead;
} // namespace network
namespace extensions {
// This is a thread safe class that registers URL request throttler entries for
// URLs being accessed in order to supervise traffic. URL requests for HTTP
// contents should register their URLs in this manager on each request.
// ExtensionThrottleManager maintains a map of URL IDs to URL request
// throttler entries. It creates URL request throttler entries when new URLs
// are registered, and does garbage collection from time to time in order to
// clean out outdated entries. URL ID consists of lowercased scheme, host, port
// and path. All URLs converted to the same ID will share the same entry.
class ExtensionThrottleManager {
virtual ~ExtensionThrottleManager();
// Creates a throttle which uses this class to prevent extensions from
// requesting a URL too often, if such a throttle is needed.
std::unique_ptr<content::URLLoaderThrottle> MaybeCreateURLLoaderThrottle(
const blink::WebURLRequest& request);
// Determine if a request to |request_url| with the given |request_load_flags|
// (see net/base/load_flags.h) should be rejected.
bool ShouldRejectRequest(const GURL& request_url, int request_load_flags);
// Determine if a redirect from the original |request_url| with the original
// |request_load_flags| (see net/base/load_flags.h) should be allowed to be
// redirected as specified by |redirect_info|.
bool ShouldRejectRedirect(const GURL& request_url,
int request_load_flags,
const net::RedirectInfo& redirect_info);
// Must be called when the |response_head| for a request has been received.
void WillProcessResponse(const GURL& response_url,
const network::ResourceResponseHead& response_head);
// Set the network status online state as specified in |is_online|.
void SetOnline(bool is_online);
void SetBackoffPolicyForTests(
std::unique_ptr<net::BackoffEntry::Policy> policy);
// Registers a new entry in this service and overrides the existing entry (if
// any) for the URL. The service will hold a reference to the entry.
// It is only used by unit tests.
void OverrideEntryForTests(const GURL& url,
std::unique_ptr<ExtensionThrottleEntry> entry);
// Sets whether to ignore net::LOAD_MAYBE_USER_GESTURE of the request for
// testing. Otherwise, requests will not be throttled when they may have been
// throttled in response to a recent user gesture, though they're still
// counted for the purpose of throttling other requests.
void SetIgnoreUserGestureLoadFlagForTests(
bool ignore_user_gesture_load_flag_for_tests);
int GetNumberOfEntriesForTests() const { return url_entries_.size(); }
// Method that allows us to transform a URL into an ID that can be used in our
// map. Resulting IDs will be lowercase and consist of the scheme, host, port
// and path (without query string, fragment, etc.).
// If the URL is invalid, the invalid spec will be returned, without any
// transformation.
std::string GetIdFromUrl(const GURL& url) const;
// Must be called for every request, returns the URL request throttler entry
// associated with the URL. The caller must inform this entry of some events.
// Please refer to extension_throttle_entry.h for further information.
ExtensionThrottleEntry* RegisterRequestUrl(const GURL& url);
// Method that does the actual work of garbage collecting.
void GarbageCollectEntries();
// Explicitly erases an entry.
// This is useful to remove those entries which have got infinite lifetime and
// thus won't be garbage collected.
// It is only used by unit tests.
void EraseEntryForTests(const GURL& url);
// Whether throttling is enabled or not.
void set_enforce_throttling(bool enforce);
bool enforce_throttling();
// Method that ensures the map gets cleaned from time to time. The period at
// which garbage collecting happens is adjustable with the
// kRequestBetweenCollecting constant.
void GarbageCollectEntriesIfNecessary();
// Maximum number of entries that we are willing to collect in our map.
static const unsigned int kMaximumNumberOfEntries;
// Number of requests that will be made between garbage collection.
static const unsigned int kRequestsBetweenCollecting;
// Map that contains a list of URL ID (composed of the scheme, host, port and
// path) and their matching ExtensionThrottleEntry.
std::map<std::string, std::unique_ptr<ExtensionThrottleEntry>> url_entries_;
// This keeps track of how many requests have been made. Used with
// GarbageCollectEntries.
unsigned int requests_since_last_gc_;
// Valid after construction.
GURL::Replacements url_id_replacements_;
bool ignore_user_gesture_load_flag_for_tests_;
// This is null when it is not set for tests.
std::unique_ptr<net::BackoffEntry::Policy> backoff_policy_for_tests_;
// Used to synchronize all public methods.
base::Lock lock_;
} // namespace extensions