When starting with a library that has a corrupted db, offer the user the option of rebuilding the db from backups, instead of trying to repair the db (which is likely to fail anyway)

src/calibre/gui2/dialogs/restore_library.py

@@ -5,12 +5,14 @@ __license__   = 'GPL v3'
 __copyright__ = '2011, Kovid Goyal <kovid@kovidgoyal.net>'
 __docformat__ = 'restructuredtext en'
 
-from PyQt4.Qt import QDialog, QLabel, QVBoxLayout, QDialogButtonBox, \
+from PyQt4.Qt import (QDialog, QLabel, QVBoxLayout, QDialogButtonBox,
-        QProgressBar, QSize, QTimer, pyqtSignal, Qt
+        QProgressBar, QSize, QTimer, pyqtSignal, Qt)
 
 from calibre.library.restore import Restore
-from calibre.gui2 import error_dialog, question_dialog, warning_dialog, \
+from calibre.gui2 import (error_dialog, question_dialog, warning_dialog,
-    info_dialog
+    info_dialog)
+from calibre import force_unicode
+from calibre.constants import filesystem_encoding
 
 class DBRestore(QDialog):
 
@@ -73,6 +75,19 @@ class DBRestore(QDialog):
             self.msg.setText(msg)
             self.pb.setValue(step)
 
+def _show_success_msg(restorer, parent=None):
+    r = restorer
+    olddb = _('The old database was saved as: %s')%force_unicode(r.olddb,
+            filesystem_encoding)
+    if r.errors_occurred:
+        warning_dialog(parent, _('Success'),
+                _('Restoring the database succeeded with some warnings'
+                    ' click Show details to see the details. %s')%olddb,
+                det_msg=r.report, show=True)
+    else:
+        info_dialog(parent, _('Success'),
+                _('Restoring database was successful. %s')%olddb, show=True,
+                show_copy_button=False)
 
 def restore_database(db, parent=None):
     if not question_dialog(parent, _('Are you sure?'), '<p>'+
@@ -102,14 +117,21 @@ def restore_database(db, parent=None):
         _('Restoring database failed, click Show details to see details'),
         det_msg=r.tb, show=True)
     else:
-        if r.errors_occurred:
+        _show_success_msg(r, parent=parent)
-            warning_dialog(parent, _('Success'),
-                    _('Restoring the database succeeded with some warnings'
-                        ' click Show details to see the details.'),
-                    det_msg=r.report, show=True)
-        else:
-            info_dialog(parent, _('Success'),
-                    _('Restoring database was successful'), show=True,
-                    show_copy_button=False)
     return True
 
+def repair_library_at(library_path):
+    d = DBRestore(None, library_path)
+    d.exec_()
+    if d.rejected:
+        return False
+    r = d.restorer
+    if r.tb is not None:
+        error_dialog(None, _('Failed'),
+        _('Restoring database failed, click Show details to see details'),
+        det_msg=r.tb, show=True)
+        return False
+    _show_success_msg(r)
+    return True
+
+

src/calibre/gui2/main.py

@@ -4,16 +4,15 @@ __copyright__ = '2008, Kovid Goyal <kovid at kovidgoyal.net>'
 import sys, os, time, socket, traceback
 from functools import partial
 
-from PyQt4.Qt import QCoreApplication, QIcon, QObject, QTimer, \
+from PyQt4.Qt import (QCoreApplication, QIcon, QObject, QTimer,
-        QThread, pyqtSignal, Qt, QProgressDialog, QString, QPixmap, \
+        QPixmap, QSplashScreen, QApplication)
-        QSplashScreen, QApplication
 
 from calibre import prints, plugins
-from calibre.constants import iswindows, __appname__, isosx, DEBUG, \
+from calibre.constants import (iswindows, __appname__, isosx, DEBUG,
-        filesystem_encoding
+        filesystem_encoding)
 from calibre.utils.ipc import ADDRESS, RC
-from calibre.gui2 import ORG_NAME, APP_UID, initialize_file_icon_provider, \
+from calibre.gui2 import (ORG_NAME, APP_UID, initialize_file_icon_provider,
-    Application, choose_dir, error_dialog, question_dialog, gprefs
+    Application, choose_dir, error_dialog, question_dialog, gprefs)
 from calibre.gui2.main_window import option_parser as _option_parser
 from calibre.utils.config import prefs, dynamic
 from calibre.library.database2 import LibraryDatabase2
@@ -110,36 +109,9 @@ def get_library_path(parent=None):
                 default_dir=get_default_library_path())
     return library_path
 
-class DBRepair(QThread):
+def repair_library(library_path):
-
+    from calibre.gui2.dialogs.restore_library import repair_library_at
-    repair_done = pyqtSignal(object, object)
+    return repair_library_at(library_path)
-    progress = pyqtSignal(object, object)
-
-    def __init__(self, library_path, parent, pd):
-        QThread.__init__(self, parent)
-        self.library_path = library_path
-        self.pd = pd
-        self.progress.connect(self._callback, type=Qt.QueuedConnection)
-
-    def _callback(self, num, is_length):
-        if is_length:
-            self.pd.setRange(0, num-1)
-            num = 0
-        self.pd.setValue(num)
-
-    def callback(self, num, is_length):
-        self.progress.emit(num, is_length)
-
-    def run(self):
-        from calibre.debug import reinit_db
-        try:
-            reinit_db(os.path.join(self.library_path, 'metadata.db'),
-                    self.callback)
-            db = LibraryDatabase2(self.library_path)
-            tb = None
-        except:
-            db, tb = None, traceback.format_exc()
-        self.repair_done.emit(db, tb)
 
 class GuiRunner(QObject):
     '''Make sure an event loop is running before starting the main work of
@@ -184,9 +156,6 @@ class GuiRunner(QObject):
         raise SystemExit(1)
 
     def initialize_db_stage2(self, db, tb):
-        repair_pd = getattr(self, 'repair_pd', None)
-        if repair_pd is not None:
-            repair_pd.cancel()
 
         if db is None and tb is not None:
             # DB Repair failed
@@ -219,23 +188,15 @@ class GuiRunner(QObject):
             db = LibraryDatabase2(self.library_path)
         except (sqlite.Error, DatabaseException):
             repair = question_dialog(self.splash_screen, _('Corrupted database'),
-                    _('Your calibre database appears to be corrupted. Do '
+                    _('Your calibre library database appears to be corrupted. Do '
-                    'you want calibre to try and repair it automatically? '
+                    'you want calibre to try and rebuild it automatically? '
+                    'The rebuild may not be completely successful. '
                     'If you say No, a new empty calibre library will be created.'),
                     det_msg=traceback.format_exc()
                     )
             if repair:
-                self.repair_pd = QProgressDialog(_('Repairing database. This '
+                if repair_library(self.library_path):
-                    'can take a very long time for a large collection'), QString(),
+                    db = LibraryDatabase2(self.library_path)
-                    0, 0)
-                self.repair_pd.setWindowModality(Qt.WindowModal)
-                self.repair_pd.show()
-
-                self.repair = DBRepair(self.library_path, self, self.repair_pd)
-                self.repair.repair_done.connect(self.initialize_db_stage2,
-                        type=Qt.QueuedConnection)
-                self.repair.start()
-                return
         except:
             error_dialog(self.splash_screen, _('Bad database location'),
                     _('Bad database location %r. Will start with '