services/network/throttling/throttling_controller.h

// Copyright 2014 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.

#ifndef SERVICES_NETWORK_THROTTLING_THROTTLING_NETWORK_CONTROLLER_H_
#define SERVICES_NETWORK_THROTTLING_THROTTLING_NETWORK_CONTROLLER_H_

#include <map>
#include <memory>
#include <string>

#include "base/component_export.h"
#include "base/macros.h"
#include "base/optional.h"
#include "base/threading/thread_checker.h"
#include "base/unguessable_token.h"

namespace network {

class NetworkConditions;
class ScopedThrottlingToken;
class ThrottlingNetworkInterceptor;

// ThrottlingController manages interceptors identified by NetLog source ID and
// profile ID and their throttling conditions.
class COMPONENT_EXPORT(NETWORK_SERVICE) ThrottlingController {
 public:
  // Applies network emulation configuration.
  static void SetConditions(const base::UnguessableToken& throttling_profile_id,
                            std::unique_ptr<NetworkConditions>);

  // Returns the profile ID for the NetLog source ID. Returns an empty string if
  // not registered.
  // Note: This method is used only from ServiceWorkerFetchDispatcher to copy
  // the profile ID from the net::URLRequest of original navigation request to
  // the network::ResourceRequest of navigation preload request when
  // S13nServiceWorker is not enabled.
  // TODO(crbug/846235): Remove this method once S13nServiceWorker is shipped.
  static base::Optional<base::UnguessableToken> GetProfileIDForNetLogSource(
      uint32_t net_log_source_id);

  // Returns the interceptor for the NetLog source ID.
  static ThrottlingNetworkInterceptor* GetInterceptor(
      uint32_t net_log_source_id);

 private:
  friend class ScopedThrottlingToken;

  ThrottlingController();
  ~ThrottlingController();

  // Registers the profile ID for the NetLog source. This is called from
  // ScopedThrottlingToken.
  static void RegisterProfileIDForNetLogSource(
      uint32_t net_log_source_id,
      const base::UnguessableToken& throttling_profile_id);

  // Unregister the NetLog source. This is called from ScopedThrottlingToken.
  static void UnregisterNetLogSource(uint32_t net_log_source_id);

  // Returns whether there is an interceptor for the profile ID. This is called
  // from ScopedThrottlingToken.
  static bool HasInterceptor(
      const base::UnguessableToken& throttling_profile_id);

  void Register(uint32_t net_log_source_id,
                const base::UnguessableToken& throttling_profile_id);
  void Unregister(uint32_t net_log_source_id);

  base::Optional<base::UnguessableToken> GetProfileID(
      uint32_t net_log_source_id);

  void SetNetworkConditions(const base::UnguessableToken& throttling_profile_id,
                            std::unique_ptr<NetworkConditions> conditions);

  ThrottlingNetworkInterceptor* FindInterceptor(uint32_t net_log_source_id);

  static ThrottlingController* instance_;

  using InterceptorMap =
      std::map<base::UnguessableToken,
               std::unique_ptr<ThrottlingNetworkInterceptor>>;
  using NetLogSourceProfileMap =
      std::map<uint32_t /* net_log_source_id */,
               base::UnguessableToken /* throttling_profile_id */>;

  InterceptorMap interceptors_;
  NetLogSourceProfileMap net_log_source_profile_map_;
  THREAD_CHECKER(thread_checker_);

  DISALLOW_COPY_AND_ASSIGN(ThrottlingController);
};

}  // namespace network

#endif  // SERVICES_NETWORK_THROTTLING_THROTTLING_NETWORK_CONTROLLER_H_