# Local status cache virtual folder: SQLite backend # Copyright (C) 2009-2011 Stewart Smith and contributors # # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation; either version 2 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program; if not, write to the Free Software # Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA import os.path import re from LocalStatus import LocalStatusFolder, magicline try: from pysqlite2 import dbapi2 as sqlite except: pass #fail only if needed later on, not on import class LocalStatusSQLiteFolder(LocalStatusFolder): """LocalStatus backend implemented with an SQLite database""" #current version of the db format cur_version = 1 def __init__(self, root, name, repository, accountname, config): super(LocalStatusSQLiteFolder, self).__init__(root, name, repository, accountname, config) #Try to establish connection try: self.connection = sqlite.connect(self.filename) except NameError: # sqlite import had failed raise UserWarning('SQLite backend chosen, but no sqlite python ' 'bindings available. Please install.') #Test if the db version is current enough and if the db is #readable. try: self.cursor = self.connection.cursor() self.cursor.execute("SELECT value from metadata WHERE key='db_version'") except sqlite.DatabaseError: #db file missing or corrupt, recreate it. self.connection.close() self.upgrade_db(0) else: # fetch db version and upgrade if needed version = int(self.cursor.fetchone()[0]) self.cursor.close() if version < LocalStatusSQLiteFolder.cur_version: self.upgrade_db(version) self.connection.close() def upgrade_db(self, from_ver): """Upgrade the sqlite format from version 'from_ver' to current""" if from_ver == 0: # from_ver==0: no db existent: plain text migration? self.create_db() # below was derived from repository.getfolderfilename() logic plaintextfilename = os.path.join( self.repository.account.getaccountmeta(), 'LocalStatus', re.sub('(^|\/)\.$','\\1dot', self.name)) # MIGRATE from plaintext if needed if os.path.exists(plaintextfilename): self.ui._msg('Migrating LocalStatus cache from plain text ' 'to sqlite database for %s:%s' %\ (self.repository, self)) file = open(plaintextfilename, "rt") line = file.readline().strip() assert(line == magicline) connection = sqlite.connect(self.filename) cursor = connection.cursor() for line in file.xreadlines(): line = line.strip() uid, flags = line.split(':') uid = long(uid) flags = [x for x in flags] flags.sort() flags = ''.join(flags) self.cursor.execute('INSERT INTO status (id,flags) VALUES (?,?)', (uid,flags)) file.close() self.connection.commit() os.rename(plaintextfilename, plaintextfilename + ".old") self.connection.close() # Future version upgrades come here... # if from_ver <= 1: ... #upgrade from 1 to 2 # if from_ver <= 2: ... #upgrade from 2 to 3 def create_db(self): """Create a new db file""" self.ui._msg('Creating new Local Status db for %s:%s' \ % (self.repository, self)) connection = sqlite.connect(self.filename) cursor = connection.cursor() cursor.execute('CREATE TABLE metadata (key VARCHAR(50) PRIMARY KEY, value VARCHAR(128))') cursor.execute("INSERT INTO metadata VALUES('db_version', '1')") cursor.execute('CREATE TABLE status (id INTEGER PRIMARY KEY, flags VARCHAR(50))') self.save() #commit if needed def isnewfolder(self): # testing the existence of the db file won't work. It is created # as soon as this class instance was intitiated. So say it is a # new folder when there are no messages at all recorded in it. return self.getmessagecount() > 0 def deletemessagelist(self): """delete all messages in the db""" self.cursor.execute('DELETE FROM status') def cachemessagelist(self): self.messagelist = {} self.cursor.execute('SELECT id,flags from status') for row in self.cursor: flags = [x for x in row[1]] self.messagelist[row[0]] = {'uid': row[0], 'flags': flags} def save(self): #Noop in this backend pass def uidexists(self,uid): self.cursor.execute('SELECT id FROM status WHERE id=:id',{'id': uid}) for row in self.cursor: if(row[0]==uid): return 1 return 0 def getmessageuidlist(self): self.cursor.execute('SELECT id from status') r = [] for row in self.cursor: r.append(row[0]) return r def getmessagecount(self): self.cursor.execute('SELECT count(id) from status'); row = self.cursor.fetchone() return row[0] def savemessage(self, uid, content, flags, rtime): if uid < 0: # We cannot assign a uid. return uid if self.uidexists(uid): # already have it self.savemessageflags(uid, flags) return uid self.messagelist[uid] = {'uid': uid, 'flags': flags, 'time': rtime} flags.sort() flags = ''.join(flags) self.cursor.execute('INSERT INTO status (id,flags) VALUES (?,?)', (uid,flags)) self.save() return uid def getmessageflags(self, uid): self.cursor.execute('SELECT flags FROM status WHERE id=:id', {'id': uid}) for row in self.cursor: flags = [x for x in row[0]] return flags assert False,"getmessageflags() called on non-existing message" def getmessagetime(self, uid): return self.messagelist[uid]['time'] def savemessageflags(self, uid, flags): self.messagelist[uid] = {'uid': uid, 'flags': flags} flags.sort() flags = ''.join(flags) self.cursor.execute('UPDATE status SET flags=? WHERE id=?',(flags,uid)) self.save() def deletemessages(self, uidlist): # Weed out ones not in self.messagelist uidlist = [uid for uid in uidlist if uid in self.messagelist] if not len(uidlist): return for uid in uidlist: del(self.messagelist[uid]) #if self.uidexists(uid): self.cursor.execute('DELETE FROM status WHERE id=:id', {'id': uid})