device_local_account_external_data_manager.h revision f2477e01787aa58f445919b809d89e252beef54f 
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
16namespace base {
17class SequencedTaskRunner;
18}
19
20namespace policy {
21
22class 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.
35class 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  virtual ~DeviceLocalAccountExternalDataManager();
58
59  // CloudExternalDataManagerBase:
60  virtual 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_
68