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_EXTENSIONS_DEVICE_LOCAL_ACCOUNT_EXTERNAL_POLICY_LOADER_H_
6#define CHROME_BROWSER_CHROMEOS_EXTENSIONS_DEVICE_LOCAL_ACCOUNT_EXTERNAL_POLICY_LOADER_H_
7
8#include "base/basictypes.h"
9#include "base/callback_forward.h"
10#include "base/compiler_specific.h"
11#include "base/files/file_path.h"
12#include "base/memory/ref_counted.h"
13#include "base/memory/scoped_ptr.h"
14#include "base/sequenced_task_runner.h"
15#include "chrome/browser/chromeos/extensions/external_cache.h"
16#include "chrome/browser/extensions/external_loader.h"
17#include "components/policy/core/common/cloud/cloud_policy_store.h"
18
19namespace chromeos {
20
21// A specialization of the ExternalLoader that serves external extensions from
22// the enterprise policy force-install list. This class is used for device-local
23// accounts in place of the ExternalPolicyLoader. The difference is that while
24// the ExternalPolicyLoader requires extensions to be downloaded on-the-fly,
25// this class caches them, allowing for offline installation.
26class DeviceLocalAccountExternalPolicyLoader
27    : public extensions::ExternalLoader,
28      public policy::CloudPolicyStore::Observer,
29      public ExternalCache::Delegate {
30 public:
31  // The list of force-installed extensions will be read from |store| and the
32  // extensions will be cached in the |cache_dir_|.
33  DeviceLocalAccountExternalPolicyLoader(policy::CloudPolicyStore* store,
34                                         const base::FilePath& cache_dir);
35
36  // While running, the cache requires exclusive write access to the
37  // |cache_dir_|.
38  bool IsCacheRunning() const;
39
40  // Start the cache. This method must only be invoked when there are no pending
41  // write operations to |cache_dir_| on any thread and none will be initiated
42  // while the cache is running.
43  void StartCache(
44      const scoped_refptr<base::SequencedTaskRunner>& cache_task_runner);
45
46  // Stop the cache. The |callback| will be invoked when the cache has shut down
47  // completely and write access to the |cache_dir_| is permitted again.
48  void StopCache(const base::Closure& callback);
49
50  // extensions::ExternalLoader:
51  virtual void StartLoading() OVERRIDE;
52
53  // policy::CloudPolicyStore::Observer:
54  virtual void OnStoreLoaded(policy::CloudPolicyStore* store) OVERRIDE;
55  virtual void OnStoreError(policy::CloudPolicyStore* store) OVERRIDE;
56
57  // ExternalCache::Delegate:
58  virtual void OnExtensionListsUpdated(
59      const base::DictionaryValue* prefs) OVERRIDE;
60
61  ExternalCache* GetExternalCacheForTesting();
62
63 private:
64  // If the cache was started, it must be stopped before |this| is destroyed.
65  virtual ~DeviceLocalAccountExternalPolicyLoader();
66
67  // Pass the current list of force-installed extensions from the |store_| to
68  // the |external_cache_|.
69  void UpdateExtensionListFromStore();
70
71  policy::CloudPolicyStore* store_;
72  const base::FilePath cache_dir_;
73  scoped_ptr<ExternalCache> external_cache_;
74
75  DISALLOW_COPY_AND_ASSIGN(DeviceLocalAccountExternalPolicyLoader);
76};
77
78}  // namespace chromeos
79
80#endif  // CHROME_BROWSER_CHROMEOS_EXTENSIONS_DEVICE_LOCAL_ACCOUNT_EXTERNAL_POLICY_LOADER_H_
81