chrome/browser/chromeos/policy/device_local_account_external_data_manager.h

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROME_BROWSER_CHROMEOS_POLICY_DEVICE_LOCAL_ACCOUNT_EXTERNAL_DATA_MANAGER_H_
   6 #define CHROME_BROWSER_CHROMEOS_POLICY_DEVICE_LOCAL_ACCOUNT_EXTERNAL_DATA_MANAGER_H_
   7
   8 #include <string>
   9
  10 #include "base/basictypes.h"
  11 #include "base/compiler_specific.h"
  12 #include "base/memory/ref_counted.h"
  13 #include "chrome/browser/chromeos/policy/cloud_external_data_manager_base.h"
  14 #include "components/policy/core/common/policy_details.h"
  15
  16 namespace base {
  17 class SequencedTaskRunner;
  18 }
  19
  20 namespace policy {
  21
  22 class ResourceCache;
  23
  24 // Downloads, verifies, caches and retrieves external data referenced by
  25 // policies.
  26 // This is the implementation for device-local accounts on Chrome OS.
  27 // The manager is created by the DeviceLocalAccountExternalDataService and must
  28 // not outlive it because the |resource_cache| is owned by the service. However,
  29 // the service is not the manager's sole owner: The manager lives as long as
  30 // either the service or a DeviceLocalAccountPolicyProvider references it. This
  31 // is necessary because a device-local account can be removed from policy (thus
  32 // removing it from the service) while a session is in progress and a provider
  33 // exists for the account. The manager is only destroyed when neither service
  34 // nor provider reference it anymore.
  35 class DeviceLocalAccountExternalDataManager
  36     : public CloudExternalDataManagerBase,
  37       public base::RefCounted<DeviceLocalAccountExternalDataManager> {
  38  private:
  39   friend class DeviceLocalAccountExternalDataService;
  40   friend class base::RefCounted<DeviceLocalAccountExternalDataManager>;
  41
  42   // |get_policy_details| is used to determine the maximum size that the
  43   // data referenced by each policy can have. Download scheduling, verification,
  44   // caching and retrieval tasks are done via the |backend_task_runner|, which
  45   // must support file I/O. Network I/O is done via the |io_task_runner|. The
  46   // manager is responsible for external data references by policies in
  47   // |policy_store|. Downloaded external data is stored in the |resource_cache|.
  48   // The data is keyed by |account_id|, allowing one cache to be shared by any
  49   // number of accounts. To ensure synchronization of operations on the shared
  50   // cache, all its users must access the cache via |backend_task_runner| only.
  51   DeviceLocalAccountExternalDataManager(
  52       const std::string& account_id,
  53       const GetChromePolicyDetailsCallback& get_policy_details,
  54       scoped_refptr<base::SequencedTaskRunner> backend_task_runner,
  55       scoped_refptr<base::SequencedTaskRunner> io_task_runner,
  56       ResourceCache* resource_cache);
  57   ~DeviceLocalAccountExternalDataManager() override;
  58
  59   // CloudExternalDataManagerBase:
  60   void OnPolicyStoreLoaded() override;
  61
  62   DISALLOW_COPY_AND_ASSIGN(DeviceLocalAccountExternalDataManager);
  63 };
  64
  65 }  // namespace policy
  66
  67 #endif  // CHROME_BROWSER_CHROMEOS_POLICY_DEVICE_LOCAL_ACCOUNT_EXTERNAL_DATA_MANAGER_H_