src/chrome/browser/extensions/api/storage/sync_storage_backend.h

   1 // Copyright 2014 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_EXTENSIONS_API_STORAGE_SYNC_STORAGE_BACKEND_H_
   6 #define CHROME_BROWSER_EXTENSIONS_API_STORAGE_SYNC_STORAGE_BACKEND_H_
   7
   8 #include <map>
   9 #include <set>
  10 #include <string>
  11
  12 #include "base/compiler_specific.h"
  13 #include "base/files/file_path.h"
  14 #include "base/memory/linked_ptr.h"
  15 #include "base/memory/ref_counted.h"
  16 #include "base/memory/scoped_ptr.h"
  17 #include "extensions/browser/api/storage/settings_observer.h"
  18 #include "extensions/browser/api/storage/settings_storage_factory.h"
  19 #include "extensions/browser/api/storage/settings_storage_quota_enforcer.h"
  20 #include "sync/api/syncable_service.h"
  21
  22 namespace syncer {
  23 class SyncErrorFactory;
  24 }
  25
  26 namespace extensions {
  27
  28 class SettingsSyncProcessor;
  29 class SyncableSettingsStorage;
  30
  31 // Manages ValueStore objects for extensions, including routing
  32 // changes from sync to them.
  33 // Lives entirely on the FILE thread.
  34 class SyncStorageBackend : public syncer::SyncableService {
  35  public:
  36   // |storage_factory| is use to create leveldb storage areas.
  37   // |base_path| is the base of the extension settings directory, so the
  38   // databases will be at base_path/extension_id.
  39   // |observers| is the list of observers to settings changes.
  40   SyncStorageBackend(
  41       const scoped_refptr<SettingsStorageFactory>& storage_factory,
  42       const base::FilePath& base_path,
  43       const SettingsStorageQuotaEnforcer::Limits& quota,
  44       const scoped_refptr<SettingsObserverList>& observers,
  45       syncer::ModelType sync_type,
  46       const syncer::SyncableService::StartSyncFlare& flare);
  47
  48   ~SyncStorageBackend() override;
  49
  50   virtual ValueStore* GetStorage(const std::string& extension_id);
  51   virtual void DeleteStorage(const std::string& extension_id);
  52
  53   // syncer::SyncableService implementation.
  54   syncer::SyncDataList GetAllSyncData(syncer::ModelType type) const override;
  55   syncer::SyncMergeResult MergeDataAndStartSyncing(
  56       syncer::ModelType type,
  57       const syncer::SyncDataList& initial_sync_data,
  58       scoped_ptr<syncer::SyncChangeProcessor> sync_processor,
  59       scoped_ptr<syncer::SyncErrorFactory> sync_error_factory) override;
  60   syncer::SyncError ProcessSyncChanges(
  61       const tracked_objects::Location& from_here,
  62       const syncer::SyncChangeList& change_list) override;
  63   void StopSyncing(syncer::ModelType type) override;
  64
  65  private:
  66   // Gets a weak reference to the storage area for a given extension,
  67   // initializing sync with some initial data if sync enabled.
  68   SyncableSettingsStorage* GetOrCreateStorageWithSyncData(
  69       const std::string& extension_id,
  70       const base::DictionaryValue& sync_data) const;
  71
  72   // Gets all extension IDs known to extension settings.  This may not be all
  73   // installed extensions.
  74   std::set<std::string> GetKnownExtensionIDs() const;
  75
  76   // Creates a new SettingsSyncProcessor for an extension.
  77   scoped_ptr<SettingsSyncProcessor> CreateSettingsSyncProcessor(
  78       const std::string& extension_id) const;
  79
  80   // The Factory to use for creating new ValueStores.
  81   const scoped_refptr<SettingsStorageFactory> storage_factory_;
  82
  83   // The base file path to use when creating new ValueStores.
  84   const base::FilePath base_path_;
  85
  86   // Quota limits (see SettingsStorageQuotaEnforcer).
  87   const SettingsStorageQuotaEnforcer::Limits quota_;
  88
  89   // The list of observers to settings changes.
  90   const scoped_refptr<SettingsObserverList> observers_;
  91
  92   // A cache of ValueStore objects that have already been created.
  93   // Ensure that there is only ever one created per extension.
  94   typedef std::map<std::string, linked_ptr<SyncableSettingsStorage> >
  95       StorageObjMap;
  96   mutable StorageObjMap storage_objs_;
  97
  98   // Current sync model type. Either EXTENSION_SETTINGS or APP_SETTINGS.
  99   syncer::ModelType sync_type_;
 100
 101   // Current sync processor, if any.
 102   scoped_ptr<syncer::SyncChangeProcessor> sync_processor_;
 103
 104   // Current sync error handler if any.
 105   scoped_ptr<syncer::SyncErrorFactory> sync_error_factory_;
 106
 107   syncer::SyncableService::StartSyncFlare flare_;
 108
 109   DISALLOW_COPY_AND_ASSIGN(SyncStorageBackend);
 110 };
 111
 112 }  // namespace extensions
 113
 114 #endif  // CHROME_BROWSER_EXTENSIONS_API_STORAGE_SYNC_STORAGE_BACKEND_H_