chrome/browser/chromeos/extensions/device_local_account_external_policy_loader.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_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
  19 namespace 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.
  26 class 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  private:
  62   // If the cache was started, it must be stopped before |this| is destroyed.
  63   virtual ~DeviceLocalAccountExternalPolicyLoader();
  64
  65   // Pass the current list of force-installed extensions from the |store_| to
  66   // the |external_cache_|.
  67   void UpdateExtensionListFromStore();
  68
  69   policy::CloudPolicyStore* store_;
  70   const base::FilePath cache_dir_;
  71   scoped_ptr<ExternalCache> external_cache_;
  72
  73   DISALLOW_COPY_AND_ASSIGN(DeviceLocalAccountExternalPolicyLoader);
  74 };
  75
  76 }  // namespace chromeos
  77
  78 #endif  // CHROME_BROWSER_CHROMEOS_EXTENSIONS_DEVICE_LOCAL_ACCOUNT_EXTERNAL_POLICY_LOADER_H_