make sqlite status cache the default

Signed-off-by: Nicolas Sebrecht <nicolas.s-dev@laposte.net>

docs/offlineimap.txt

@@ -200,16 +200,20 @@ done this yet, do it :). See the folderfilter section in offlineimap.conf.
 
 3. The cache.
 +
-The default status cache is a plain text file that will write out the complete
-file for each single new message (or even changed flag) to a temporary file.
-If you have plenty of files in a folder, this is a few hundred kilo to
-megabytes for each mail and is bound to make things slower. I recommend to use
-the sqlite backend for that. See the status_backend = sqlite setting in the
-offlineimap.conf. You will need to have python-sqlite installed in order to
-use this. This will save you plenty of disk activity. Do note that
-the sqlite backend is still considered experimental as it has only been
-included recently (although a loss of your status cache should not be a
-tragedy as that file can be rebuilt automatically)
+OfflineImap caches the state of the synchronisation to e.g. be able to determine
+if a mail has been added or deleted on either side.
++
+The historical status cache is a plain text file that writes out the complete
+file for each single new message (or even changed flag) to a temporary file. If
+you have plenty of files in a folder, this is a few hundred kilo to megabytes
+for each mail and is bound to make things slow. The default status cache uses
+sqlite. This saves plenty of disk activity. The sqlite engine and the Python
+sqlite module must installed. See the status_backend = plain setting in the
+offlineimap.conf.
++
+If you switch the backend from plain to sqlite, you may want to delete the old
+cache directory in <metadata>/Account-<account>/LocalStatus manually once
+you are sure that things work.
 
 4. Use quick sync.
 +

offlineimap.conf

@@ -302,26 +302,16 @@ remoterepository = RemoteExample
 #
 # This example plays a sound file of your chosing when new mail arrives.
 #
-#newmail_hook = lambda: os.system("cvlc --play-and-stop --play-and-exit /path/to/sound/file.mp3" +
-#				 " > /dev/null 2>&1")
+#newmail_hook = lambda: os.system(
+#"cvlc --play-and-stop --play-and-exit /path/to/sound/file.mp3 > /dev/null 2>&1")
 
 
 # This option stands in the [Account Test] section.
 #
-# OfflineImap caches the state of the synchronisation to e.g. be able to
-# determine if a mail has been added or deleted on either side.
+# The historical backend is 'plain' which writes out the state in plain text
+# files. See manual.
 #
-# The default and historical backend is 'plain' which writes out the
-# state in plain text files. On Repositories with large numbers of
-# mails, the performance might not be optimal, as we write out the
-# complete file for each change.  Another new backend 'sqlite' is
-# available which stores the status in sqlite databases.
-#
-# If you switch the backend, you may want to delete the old cache
-# directory in ~/.offlineimap/Account-<account>/LocalStatus manually
-# once you are sure that things work.
-#
-#status_backend = plain
+#status_backend = sqlite
 
 
 # This option stands in the [Account Test] section.

offlineimap/repository/LocalStatus.py

@@ -38,7 +38,7 @@ class LocalStatusRepository(BaseRepository):
         }
 
         # Set class and root for the configured backend
-        self.setup_backend(self.account.getconf('status_backend', 'plain'))
+        self.setup_backend(self.account.getconf('status_backend', 'sqlite'))
 
         if not os.path.exists(self.root):
             os.mkdir(self.root, 0o700)
@@ -71,8 +71,8 @@ class LocalStatusRepository(BaseRepository):
 
             # if backend contains data, import it to folder.
             if not folderbk.isnewfolder():
-                self.ui._msg('Migrating LocalStatus cache from %s to %s " \
-                    "status folder for %s:%s'%
+                self.ui._msg("Migrating LocalStatus cache from %s to %s "
+                    "status folder for %s:%s"%
                     (bk, self._backend, self.name, folder.name))
 
                 folderbk.cachemessagelist()