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.
5 #ifndef COMPONENTS_WEBDATA_COMMON_WEB_DATA_SERVICE_BACKEND_H_
6 #define COMPONENTS_WEBDATA_COMMON_WEB_DATA_SERVICE_BACKEND_H_
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/ref_counted_delete_on_message_loop.h"
14 #include "base/memory/scoped_ptr.h"
15 #include "base/memory/scoped_vector.h"
16 #include "components/webdata/common/web_database_service.h"
17 #include "components/webdata/common/webdata_export.h"
20 class WebDatabaseTable;
22 class WebDataRequestManager;
24 namespace tracked_objects {
28 // WebDataServiceBackend handles all database tasks posted by
29 // WebDatabaseService. It is refcounted to allow asynchronous destruction on the
32 // TODO(caitkp): Rename this class to WebDatabaseBackend.
34 class WEBDATA_EXPORT WebDataServiceBackend
35 : public base::RefCountedDeleteOnMessageLoop<WebDataServiceBackend> {
39 virtual ~Delegate() {}
41 // Invoked when the backend has finished loading the db.
42 virtual void DBLoaded(sql::InitStatus status) = 0;
45 WebDataServiceBackend(const base::FilePath& path,
47 const scoped_refptr<base::MessageLoopProxy>& db_thread);
49 // Must call only before InitDatabaseWithCallback.
50 void AddTable(scoped_ptr<WebDatabaseTable> table);
52 // Initializes the database and notifies caller via callback when complete.
53 // Callback is called synchronously.
56 // Opens the database file from the profile path if an init has not yet been
57 // attempted. Separated from the constructor to ease construction/destruction
58 // of this object on one thread but database access on the DB thread. Returns
59 // the status of the database.
60 sql::InitStatus LoadDatabaseIfNecessary();
62 // Shuts down database. |should_reinit| tells us whether or not it should be
63 // possible to re-initialize the DB after the shutdown.
64 void ShutdownDatabase(bool should_reinit);
66 // Task wrappers to update requests and and notify |request_manager_|. These
67 // are used in cases where the request is being made from the UI thread and an
68 // asyncronous callback is required to notify the client of |request|'s
70 void DBWriteTaskWrapper(
71 const WebDatabaseService::WriteTask& task,
72 scoped_ptr<WebDataRequest> request);
73 void DBReadTaskWrapper(
74 const WebDatabaseService::ReadTask& task,
75 scoped_ptr<WebDataRequest> request);
77 // Task runners to run database tasks.
78 void ExecuteWriteTask(const WebDatabaseService::WriteTask& task);
79 scoped_ptr<WDTypedResult> ExecuteReadTask(
80 const WebDatabaseService::ReadTask& task);
82 const scoped_refptr<WebDataRequestManager>& request_manager() {
83 return request_manager_;
86 WebDatabase* database() { return db_.get(); }
89 friend class base::RefCountedDeleteOnMessageLoop<WebDataServiceBackend>;
90 friend class base::DeleteHelper<WebDataServiceBackend>;
92 virtual ~WebDataServiceBackend();
95 // Commit the current transaction.
98 // Path to database file.
99 base::FilePath db_path_;
101 // The tables that participate in managing the database. These are
102 // owned here but other than that this class does nothing with
103 // them. Their initialization is in whatever factory creates
104 // WebDatabaseService, and lookup by type is provided by the
105 // WebDatabase class. The tables need to be owned by this refcounted
106 // object, or they themselves would need to be refcounted. Owning
107 // them here rather than having WebDatabase own them makes for
108 // easier unit testing of WebDatabase.
109 ScopedVector<WebDatabaseTable> tables_;
111 scoped_ptr<WebDatabase> db_;
113 // Keeps track of all pending requests made to the db.
114 scoped_refptr<WebDataRequestManager> request_manager_;
116 // State of database initialization. Used to prevent the executing of tasks
117 // before the db is ready.
118 sql::InitStatus init_status_;
120 // True if an attempt has been made to load the database (even if the attempt
121 // fails), used to avoid continually trying to reinit if the db init fails.
124 // Delegate. See the class definition above for more information.
125 scoped_ptr<Delegate> delegate_;
127 DISALLOW_COPY_AND_ASSIGN(WebDataServiceBackend);
130 #endif // COMPONENTS_WEBDATA_COMMON_WEB_DATA_SERVICE_BACKEND_H_