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 // Chromium settings and storage represent user-selected preferences and 6 // information and MUST not be extracted, overwritten or modified except 7 // through Chromium defined APIs. 8 9 #ifndef COMPONENTS_WEBDATA_COMMON_WEB_DATABASE_SERVICE_H_ 10 #define COMPONENTS_WEBDATA_COMMON_WEB_DATABASE_SERVICE_H_ 11 12 #include "base/basictypes.h" 13 #include "base/callback_forward.h" 14 #include "base/compiler_specific.h" 15 #include "base/files/file_path.h" 16 #include "base/memory/ref_counted.h" 17 #include "base/memory/ref_counted_delete_on_message_loop.h" 18 #include "base/memory/scoped_ptr.h" 19 #include "base/memory/weak_ptr.h" 20 #include "base/message_loop/message_loop_proxy.h" 21 #include "base/observer_list.h" 22 #include "components/webdata/common/web_data_service_base.h" 23 #include "components/webdata/common/web_database.h" 24 #include "components/webdata/common/webdata_export.h" 25 26 class WebDataServiceBackend; 27 class WebDataRequestManager; 28 29 namespace content { 30 class BrowserContext; 31 } 32 33 namespace tracked_objects { 34 class Location; 35 } 36 37 class WDTypedResult; 38 class WebDataServiceConsumer; 39 40 41 //////////////////////////////////////////////////////////////////////////////// 42 // 43 // WebDatabaseService defines the interface to a generic data repository 44 // responsible for controlling access to the web database (metadata associated 45 // with web pages). 46 // 47 //////////////////////////////////////////////////////////////////////////////// 48 49 class WEBDATA_EXPORT WebDatabaseService 50 : public base::RefCountedDeleteOnMessageLoop<WebDatabaseService> { 51 public: 52 typedef base::Callback<scoped_ptr<WDTypedResult>(WebDatabase*)> ReadTask; 53 typedef base::Callback<WebDatabase::State(WebDatabase*)> WriteTask; 54 55 // Types for managing DB loading callbacks. 56 typedef base::Closure DBLoadedCallback; 57 typedef base::Callback<void(sql::InitStatus)> DBLoadErrorCallback; 58 59 // Takes the path to the WebDatabase file. 60 // WebDatabaseService lives on |ui_thread| and posts tasks to |db_thread|. 61 WebDatabaseService(const base::FilePath& path, 62 const scoped_refptr<base::MessageLoopProxy>& ui_thread, 63 const scoped_refptr<base::MessageLoopProxy>& db_thread); 64 65 // Adds |table| as a WebDatabaseTable that will participate in 66 // managing the database, transferring ownership. All calls to this 67 // method must be made before |LoadDatabase| is called. 68 virtual void AddTable(scoped_ptr<WebDatabaseTable> table); 69 70 // Initializes the web database service. 71 virtual void LoadDatabase(); 72 73 // Unloads the database and shuts down the service. 74 virtual void ShutdownDatabase(); 75 76 // Gets a pointer to the WebDatabase (owned by WebDatabaseService). 77 // TODO(caitkp): remove this method once SyncServices no longer depend on it. 78 virtual WebDatabase* GetDatabaseOnDB() const; 79 80 // Returns a pointer to the WebDataServiceBackend. 81 scoped_refptr<WebDataServiceBackend> GetBackend() const; 82 83 // Schedule an update/write task on the DB thread. 84 virtual void ScheduleDBTask( 85 const tracked_objects::Location& from_here, 86 const WriteTask& task); 87 88 // Schedule a read task on the DB thread. 89 virtual WebDataServiceBase::Handle ScheduleDBTaskWithResult( 90 const tracked_objects::Location& from_here, 91 const ReadTask& task, 92 WebDataServiceConsumer* consumer); 93 94 // Cancel an existing request for a task on the DB thread. 95 // TODO(caitkp): Think about moving the definition of the Handle type to 96 // somewhere else. 97 virtual void CancelRequest(WebDataServiceBase::Handle h); 98 99 // Register a callback to be notified that the database has loaded. Multiple 100 // callbacks may be registered, and each will be called at most once 101 // (following a successful database load), then cleared. 102 // Note: if the database load is already complete, then the callback will NOT 103 // be stored or called. 104 void RegisterDBLoadedCallback(const DBLoadedCallback& callback); 105 106 // Register a callback to be notified that the database has failed to load. 107 // Multiple callbacks may be registered, and each will be called at most once 108 // (following a database load failure), then cleared. 109 // Note: if the database load is already complete, then the callback will NOT 110 // be stored or called. 111 void RegisterDBErrorCallback(const DBLoadErrorCallback& callback); 112 113 bool db_loaded() const { return db_loaded_; }; 114 115 private: 116 class BackendDelegate; 117 friend class BackendDelegate; 118 friend class base::RefCountedDeleteOnMessageLoop<WebDatabaseService>; 119 friend class base::DeleteHelper<WebDatabaseService>; 120 121 typedef std::vector<DBLoadedCallback> LoadedCallbacks; 122 typedef std::vector<DBLoadErrorCallback> ErrorCallbacks; 123 124 virtual ~WebDatabaseService(); 125 126 void OnDatabaseLoadDone(sql::InitStatus status); 127 128 base::FilePath path_; 129 130 // The primary owner is |WebDatabaseService| but is refcounted because 131 // PostTask on DB thread may outlive us. 132 scoped_refptr<WebDataServiceBackend> wds_backend_; 133 134 // Callbacks to be called once the DB has loaded. 135 LoadedCallbacks loaded_callbacks_; 136 137 // Callbacks to be called if the DB has failed to load. 138 ErrorCallbacks error_callbacks_; 139 140 // True if the WebDatabase has loaded. 141 bool db_loaded_; 142 143 scoped_refptr<base::MessageLoopProxy> db_thread_; 144 145 // All vended weak pointers are invalidated in ShutdownDatabase(). 146 base::WeakPtrFactory<WebDatabaseService> weak_ptr_factory_; 147 148 DISALLOW_COPY_AND_ASSIGN(WebDatabaseService); 149 }; 150 151 #endif // COMPONENTS_WEBDATA_COMMON_WEB_DATABASE_SERVICE_H_ 152
