code.delx.au - offlineimap/blob - head/offlineimap/folder/Base.py

   1 # Base folder support
   2 # Copyright (C) 2002 John Goerzen
   3 # <jgoerzen@complete.org>
   4 #
   5 #    This program is free software; you can redistribute it and/or modify
   6 #    it under the terms of the GNU General Public License as published by
   7 #    the Free Software Foundation; either version 2 of the License, or
   8 #    (at your option) any later version.
   9 #
  10 #    This program is distributed in the hope that it will be useful,
  11 #    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 #    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 #    GNU General Public License for more details.
  14 #
  15 #    You should have received a copy of the GNU General Public License
  16 #    along with this program; if not, write to the Free Software
  17 #    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18
  19 import __main__
  20 from threading import *
  21 from offlineimap import threadutil
  22 from offlineimap.threadutil import InstanceLimitedThread
  23
  24 class BaseFolder:
  25     def getname(self):
  26         """Returns name"""
  27         return self.name
  28
  29     def suggeststhreads(self):
  30         """Returns true if this folder suggests using threads for actions;
  31         false otherwise.  Probably only IMAP will return true."""
  32         return 0
  33
  34     def waitforthread(self):
  35         """For threading folders, waits until there is a resource available
  36         before firing off a thread.  For all others, returns immediately."""
  37         pass
  38
  39     def getcopyinstancelimit(self):
  40         """For threading folders, returns the instancelimitname for
  41         InstanceLimitedThreads."""
  42         raise NotImplementedException
  43
  44     def getvisiblename(self):
  45         return self.name
  46
  47     def getroot(self):
  48         """Returns the root of the folder, in a folder-specific fashion."""
  49         return self.root
  50
  51     def getsep(self):
  52         """Returns the separator for this folder type."""
  53         return self.sep
  54
  55     def getfullname(self):
  56         if self.getroot():
  57             return self.getroot() + self.getsep() + self.getname()
  58         else:
  59             return self.getname()
  60
  61     def isuidvalidityok(self, remotefolder):
  62         raise NotImplementedException
  63
  64     def getuidvalidity(self):
  65         raise NotImplementedException
  66
  67     def saveuidvalidity(self, newval):
  68         raise NotImplementedException
  69
  70     def cachemessagelist(self):
  71         """Reads the message list from disk or network and stores it in
  72         memory for later use.  This list will not be re-read from disk or
  73         memory unless this function is called again."""
  74         raise NotImplementedException
  75
  76     def getmessagelist(self):
  77         """Gets the current message list.
  78         You must call cachemessagelist() before calling this function!"""
  79         raise NotImplementedException
  80
  81     def getmessage(self, uid):
  82         """Returns the content of the specified message."""
  83         raise NotImplementedException
  84
  85     def savemessage(self, uid, content, flags):
  86         """Writes a new message, with the specified uid.
  87         If the uid is < 0, the backend should assign a new uid and return it.
  88
  89         If the backend cannot assign a new uid, it returns the uid passed in
  90         WITHOUT saving the message.
  91
  92         IMAP backend should be the only one that can assign a new uid.
  93
  94         If the uid is > 0, the backend should set the uid to this, if it can.
  95         If it cannot set the uid to that, it will save it anyway.
  96         It will return the uid assigned in any case.
  97         """
  98         raise NotImplementedException
  99
 100     def getmessageflags(self, uid):
 101         """Returns the flags for the specified message."""
 102         raise NotImplementedException
 103
 104     def savemessageflags(self, uid, flags):
 105         """Sets the specified message's flags to the given set."""
 106         raise NotImplementedException
 107
 108     def addmessageflags(self, uid, flags):
 109         """Adds the specified flags to the message's flag set.  If a given
 110         flag is already present, it will not be duplicated."""
 111         newflags = self.getmessageflags(uid)
 112         for flag in flags:
 113             if not flag in newflags:
 114                 newflags.append(flag)
 115         newflags.sort()
 116         self.savemessageflags(uid, newflags)
 117
 118     def addmessagesflags(self, uidlist, flags):
 119         for uid in uidlist:
 120             self.addmessageflags(uid)
 121
 122     def deletemessageflags(self, uid, flags):
 123         """Removes each flag given from the message's flag set.  If a given
 124         flag is already removed, no action will be taken for that flag."""
 125         newflags = self.getmessageflags(uid)
 126         for flag in flags:
 127             if flag in newflags:
 128                 newflags.remove(flag)
 129         newflags.sort()
 130         self.savemessageflags(uid, newflags)
 131
 132     def deletemessage(self, uid):
 133         raise NotImplementedException
 134
 135     def deletemessages(self, uidlist):
 136         for uid in uidlist:
 137             self.deletemessage(uid)
 138
 139     def syncmessagesto_neguid(self, dest, applyto):
 140         """Pass 1 of folder synchronization.
 141
 142         Look for messages in self with a negative uid.  These are messages in
 143         Maildirs that were not added by us.  Try to add them to the dests,
 144         and once that succeeds, get the UID, add it to the others for real,
 145         add it to local for real, and delete the fake one."""
 146
 147         for uid in self.getmessagelist().keys():
 148             if uid >= 0:
 149                 continue
 150             __main__.ui.copyingmessage(uid, self, applyto)
 151             successobject = None
 152             successuid = None
 153             message = self.getmessage(uid)
 154             flags = self.getmessageflags(uid)
 155             for tryappend in applyto:
 156                 successuid = tryappend.savemessage(uid, message, flags)
 157                 if successuid > 0:
 158                     successobject = tryappend
 159                     break
 160             # Did we succeed?
 161             if successobject != None:
 162                 # Copy the message to the other remote servers.
 163                 for appendserver in [x for x in applyto if x != successobject]:
 164                     appendserver.savemessage(successuid, message, flags)
 165                 # Copy it to its new name on the local server and delete
 166                 # the one without a UID.
 167                 self.savemessage(successuid, message, flags)
 168                 self.deletemessage(uid)
 169             else:
 170                 # Did not find any server to take this message.  Ignore.
 171                 pass
 172
 173     def copymessageto(self, uid, applyto):
 174         __main__.ui.copyingmessage(uid, self, applyto)
 175         message = self.getmessage(uid)
 176         flags = self.getmessageflags(uid)
 177         for object in applyto:
 178             newuid = object.savemessage(uid, message, flags)
 179             if newuid > 0 and newuid != uid:
 180                 # Change the local uid.
 181                 self.savemessage(newuid, message, flags)
 182                 self.deletemessage(uid)
 183                 uid = newuid
 184
 185
 186     def syncmessagesto_copy(self, dest, applyto):
 187         """Pass 2 of folder synchronization.
 188
 189         Look for messages present in self but not in dest.  If any, add
 190         them to dest."""
 191         threads = []
 192
 193         for uid in self.getmessagelist().keys():
 194             if uid < 0:                 # Ignore messages that pass 1 missed.
 195                 continue
 196             if not uid in dest.getmessagelist():
 197                 if self.suggeststhreads():
 198                     self.waitforthread()
 199                     thread = InstanceLimitedThread(\
 200                         self.getcopyinstancelimit(),
 201                         target = self.copymessageto,
 202                         args = (uid, applyto))
 203                     thread.start()
 204                     threads.append(thread)
 205                 else:
 206                     self.copymessageto(uid, applyto)
 207         for thread in threads:
 208             thread.join()
 209
 210     def syncmessagesto_delete(self, dest, applyto):
 211         """Pass 3 of folder synchronization.
 212
 213         Look for message present in dest but not in self.
 214         If any, delete them."""
 215         deletelist = []
 216         for uid in dest.getmessagelist().keys():
 217             if uid < 0:
 218                 continue
 219             if not uid in self.getmessagelist():
 220                 deletelist.append(uid)
 221         if len(deletelist):
 222             __main__.ui.deletingmessages(deletelist, applyto)
 223             for object in applyto:
 224                 object.deletemessages(deletelist)
 225
 226     def syncmessagesto_flags(self, dest, applyto):
 227         """Pass 4 of folder synchronization.
 228
 229         Look for any flag matching issues -- set dest message to have the
 230         same flags that we have."""
 231         for uid in self.getmessagelist().keys():
 232             if uid < 0:                 # Ignore messages missed by pass 1
 233                 continue
 234             selfflags = self.getmessageflags(uid)
 235             destflags = dest.getmessageflags(uid)
 236
 237             addflags = [x for x in selfflags if x not in destflags]
 238             if len(addflags):
 239                 __main__.ui.addingflags(uid, addflags, applyto)
 240                 for object in applyto:
 241                     object.addmessageflags(uid, addflags)
 242
 243             delflags = [x for x in destflags if x not in selfflags]
 244             if len(delflags):
 245                 __main__.ui.deletingflags(uid, delflags, applyto)
 246                 for object in applyto:
 247                     object.deletemessageflags(uid, delflags)
 248
 249     def syncmessagesto(self, dest, applyto = None):
 250         """Syncs messages in this folder to the destination.
 251         If applyto is specified, it should be a list of folders (don't forget
 252         to include dest!) to which all write actions should be applied.
 253         It defaults to [dest] if not specified.  It is important that
 254         the UID generator be listed first in applyto; that is, the other
 255         applyto ones should be the ones that "copy" the main action."""
 256         if applyto == None:
 257             applyto = [dest]
 258
 259         self.syncmessagesto_neguid(dest, applyto)
 260         self.syncmessagesto_copy(dest, applyto)
 261         self.syncmessagesto_delete(dest, applyto)
 262
 263         # Now, the message lists should be identical wrt the uids present.
 264         # (except for potential negative uids that couldn't be placed
 265         # anywhere)
 266
 267         self.syncmessagesto_flags(dest, applyto)
 268
 269