chrome/browser/sessions/base_session_service.h

   1 // Copyright (c) 2012 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_SESSIONS_BASE_SESSION_SERVICE_H_
   6 #define CHROME_BROWSER_SESSIONS_BASE_SESSION_SERVICE_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/callback.h"
  10 #include "base/files/file_path.h"
  11 #include "base/gtest_prod_util.h"
  12 #include "base/location.h"
  13 #include "base/memory/ref_counted.h"
  14 #include "base/memory/scoped_vector.h"
  15 #include "base/memory/weak_ptr.h"
  16 #include "base/task/cancelable_task_tracker.h"
  17 #include "base/threading/sequenced_worker_pool.h"
  18 #include "components/sessions/session_id.h"
  19 #include "url/gurl.h"
  20
  21 class Profile;
  22 class SessionBackend;
  23 class SessionCommand;
  24
  25 namespace sessions {
  26 class SerializedNavigationEntry;
  27 }
  28
  29 // BaseSessionService is the super class of both tab restore service and
  30 // session service. It contains commonality needed by both, in particular
  31 // it manages a set of SessionCommands that are periodically sent to a
  32 // SessionBackend.
  33 class BaseSessionService {
  34  public:
  35   // Identifies the type of session service this is. This is used by the
  36   // backend to determine the name of the files.
  37   enum SessionType {
  38     SESSION_RESTORE,
  39     TAB_RESTORE
  40   };
  41
  42   // Creates a new BaseSessionService. After creation you need to invoke
  43   // Init.
  44   // |type| gives the type of session service, |profile| the profile and
  45   // |path| the path to save files to. If |profile| is non-NULL, |path| is
  46   // ignored and instead the path comes from the profile.
  47   BaseSessionService(SessionType type,
  48                      Profile* profile,
  49                      const base::FilePath& path);
  50
  51   Profile* profile() const { return profile_; }
  52
  53   // Deletes the last session.
  54   void DeleteLastSession();
  55
  56   typedef base::Callback<void(ScopedVector<SessionCommand>)>
  57       InternalGetCommandsCallback;
  58
  59  protected:
  60   virtual ~BaseSessionService();
  61
  62   // Returns the backend.
  63   SessionBackend* backend() const { return backend_.get(); }
  64
  65   // Returns the set of commands that needed to be scheduled. The commands
  66   // in the vector are owned by BaseSessionService, until they are scheduled
  67   // on the backend at which point the backend owns the commands.
  68   std::vector<SessionCommand*>&  pending_commands() {
  69     return pending_commands_;
  70   }
  71
  72   // Whether the next save resets the file before writing to it.
  73   void set_pending_reset(bool value) { pending_reset_ = value; }
  74   bool pending_reset() const { return pending_reset_; }
  75
  76   // Returns the number of commands sent down since the last reset.
  77   int commands_since_reset() const { return commands_since_reset_; }
  78
  79   // Schedules a command. This adds |command| to pending_commands_ and
  80   // invokes StartSaveTimer to start a timer that invokes Save at a later
  81   // time.
  82   virtual void ScheduleCommand(SessionCommand* command);
  83
  84   // Starts the timer that invokes Save (if timer isn't already running).
  85   void StartSaveTimer();
  86
  87   // Saves pending commands to the backend. This is invoked from the timer
  88   // scheduled by StartSaveTimer.
  89   virtual void Save();
  90
  91   // Creates a SessionCommand that represents a navigation.
  92   SessionCommand* CreateUpdateTabNavigationCommand(
  93       SessionID::id_type command_id,
  94       SessionID::id_type tab_id,
  95       const sessions::SerializedNavigationEntry& navigation);
  96
  97   // Creates a SessionCommand that represents marking a tab as an application.
  98   SessionCommand* CreateSetTabExtensionAppIDCommand(
  99       SessionID::id_type command_id,
 100       SessionID::id_type tab_id,
 101       const std::string& extension_id);
 102
 103   // Creates a SessionCommand that containing user agent override used by a
 104   // tab's navigations.
 105   SessionCommand* CreateSetTabUserAgentOverrideCommand(
 106       SessionID::id_type command_id,
 107       SessionID::id_type tab_id,
 108       const std::string& user_agent_override);
 109
 110   // Creates a SessionCommand stores a browser window's app name.
 111   SessionCommand* CreateSetWindowAppNameCommand(
 112       SessionID::id_type command_id,
 113       SessionID::id_type window_id,
 114       const std::string& app_name);
 115
 116   // Converts a SessionCommand previously created by
 117   // CreateUpdateTabNavigationCommand into a
 118   // sessions::SerializedNavigationEntry. Returns true on success. If
 119   // successful |tab_id| is set to the id of the restored tab.
 120   bool RestoreUpdateTabNavigationCommand(
 121       const SessionCommand& command,
 122       sessions::SerializedNavigationEntry* navigation,
 123       SessionID::id_type* tab_id);
 124
 125   // Extracts a SessionCommand as previously created by
 126   // CreateSetTabExtensionAppIDCommand into the tab id and application
 127   // extension id.
 128   bool RestoreSetTabExtensionAppIDCommand(
 129       const SessionCommand& command,
 130       SessionID::id_type* tab_id,
 131       std::string* extension_app_id);
 132
 133   // Extracts a SessionCommand as previously created by
 134   // CreateSetTabUserAgentOverrideCommand into the tab id and user agent.
 135   bool RestoreSetTabUserAgentOverrideCommand(
 136       const SessionCommand& command,
 137       SessionID::id_type* tab_id,
 138       std::string* user_agent_override);
 139
 140   // Extracts a SessionCommand as previously created by
 141   // CreateSetWindowAppNameCommand into the window id and application name.
 142   bool RestoreSetWindowAppNameCommand(
 143       const SessionCommand& command,
 144       SessionID::id_type* window_id,
 145       std::string* app_name);
 146
 147   // Returns true if the entry at specified |url| should be written to disk.
 148   bool ShouldTrackEntry(const GURL& url);
 149
 150   // Invokes SessionBackend::ReadLastSessionCommands with callback on the
 151   // backend thread.
 152   // If testing, SessionBackend::ReadLastSessionCommands is invoked directly.
 153   base::CancelableTaskTracker::TaskId ScheduleGetLastSessionCommands(
 154       const InternalGetCommandsCallback& callback,
 155       base::CancelableTaskTracker* tracker);
 156
 157   // This posts the task to the SequencedWorkerPool, or run immediately
 158   // if the SequencedWorkerPool has been shutdown.
 159   bool RunTaskOnBackendThread(const tracked_objects::Location& from_here,
 160                               const base::Closure& task);
 161
 162   // Max number of navigation entries in each direction we'll persist.
 163   static const int max_persist_navigation_count;
 164
 165  private:
 166   friend class BetterSessionRestoreCrashTest;
 167
 168   // The profile. This may be null during testing.
 169   Profile* profile_;
 170
 171   // The backend.
 172   scoped_refptr<SessionBackend> backend_;
 173
 174   // Used to invoke Save.
 175   base::WeakPtrFactory<BaseSessionService> weak_factory_;
 176
 177   // Commands we need to send over to the backend.
 178   std::vector<SessionCommand*>  pending_commands_;
 179
 180   // Whether the backend file should be recreated the next time we send
 181   // over the commands.
 182   bool pending_reset_;
 183
 184   // The number of commands sent to the backend before doing a reset.
 185   int commands_since_reset_;
 186
 187   // A token to make sure that all tasks will be serialized.
 188   base::SequencedWorkerPool::SequenceToken sequence_token_;
 189
 190   DISALLOW_COPY_AND_ASSIGN(BaseSessionService);
 191 };
 192
 193 #endif  // CHROME_BROWSER_SESSIONS_BASE_SESSION_SERVICE_H_