docker-offlineimap/offlineimap/folder/Base.py
Sebastian Spaeth fc03475b9e Remove thread Lock() when saving UIDvalidity
Removing this lock makes the function not threadsafe, but then it is
only ever called from one thread, the main account syncer. Also, it
doesn't make it worse than most of the other functions in that class
which are also not threadsafe.

Removing this makes the code simpler, and removes the need to import the
threading module.

Signed-off-by: Sebastian Spaeth <Sebastian@SSpaeth.de>
Signed-off-by: Nicolas Sebrecht <nicolas.s-dev@laposte.net>
2011-03-06 18:33:11 +01:00

432 lines
16 KiB
Python

# Base folder support
# Copyright (C) 2002 John Goerzen
# <jgoerzen@complete.org>
#
# 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
from offlineimap import threadutil
from offlineimap.ui import getglobalui
import os.path
import re
import sys
import traceback
class BaseFolder:
def __init__(self):
self.ui = getglobalui()
def getname(self):
"""Returns name"""
return self.name
def suggeststhreads(self):
"""Returns true if this folder suggests using threads for actions;
false otherwise. Probably only IMAP will return true."""
return 0
def waitforthread(self):
"""For threading folders, waits until there is a resource available
before firing off a thread. For all others, returns immediately."""
pass
def getcopyinstancelimit(self):
"""For threading folders, returns the instancelimitname for
InstanceLimitedThreads."""
raise NotImplementedException
def storesmessages(self):
"""Should be true for any backend that actually saves message bodies.
(Almost all of them). False for the LocalStatus backend. Saves
us from having to slurp up messages just for localstatus purposes."""
return 1
def getvisiblename(self):
return self.name
def getrepository(self):
"""Returns the repository object that this folder is within."""
return self.repository
def getroot(self):
"""Returns the root of the folder, in a folder-specific fashion."""
return self.root
def getsep(self):
"""Returns the separator for this folder type."""
return self.sep
def getfullname(self):
if self.getroot():
return self.getroot() + self.getsep() + self.getname()
else:
return self.getname()
def getfolderbasename(self):
foldername = self.getname()
foldername = foldername.replace(self.repository.getsep(), '.')
foldername = re.sub('/\.$', '/dot', foldername)
foldername = re.sub('^\.$', 'dot', foldername)
return foldername
def isuidvalidityok(self):
"""Does the cached UID match the real UID
If required it caches the UID. In this case the function is not
threadsafe. So don't attempt to call it from concurrent threads."""
if self.getsaveduidvalidity() != None:
return self.getsaveduidvalidity() == self.getuidvalidity()
else:
self.saveuidvalidity()
return 1
def _getuidfilename(self):
return os.path.join(self.repository.getuiddir(),
self.getfolderbasename())
def getsaveduidvalidity(self):
if hasattr(self, '_base_saved_uidvalidity'):
return self._base_saved_uidvalidity
uidfilename = self._getuidfilename()
if not os.path.exists(uidfilename):
self._base_saved_uidvalidity = None
else:
file = open(uidfilename, "rt")
self._base_saved_uidvalidity = long(file.readline().strip())
file.close()
return self._base_saved_uidvalidity
def saveuidvalidity(self):
"""Save the UID value of the folder to the status
This function is not threadsafe, so don't attempt to call it
from concurrent threads."""
newval = self.getuidvalidity()
uidfilename = self._getuidfilename()
file = open(uidfilename + ".tmp", "wt")
file.write("%d\n" % newval)
file.close()
os.rename(uidfilename + ".tmp", uidfilename)
self._base_saved_uidvalidity = newval
def getuidvalidity(self):
raise NotImplementedException
def cachemessagelist(self):
"""Reads the message list from disk or network and stores it in
memory for later use. This list will not be re-read from disk or
memory unless this function is called again."""
raise NotImplementedException
def getmessagelist(self):
"""Gets the current message list.
You must call cachemessagelist() before calling this function!"""
raise NotImplementedException
def getmessage(self, uid):
"""Returns the content of the specified message."""
raise NotImplementedException
def savemessage(self, uid, content, flags, rtime):
"""Writes a new message, with the specified uid.
If the uid is < 0, the backend should assign a new uid and return it.
If the backend cannot assign a new uid, it returns the uid passed in
WITHOUT saving the message.
If the backend CAN assign a new uid, but cannot find out what this UID
is (as is the case with many IMAP servers), it returns 0 but DOES save
the message.
IMAP backend should be the only one that can assign a new uid.
If the uid is > 0, the backend should set the uid to this, if it can.
If it cannot set the uid to that, it will save it anyway.
It will return the uid assigned in any case.
"""
raise NotImplementedException
def getmessagetime(self, uid):
"""Return the received time for the specified message."""
raise NotImplementedException
def getmessageflags(self, uid):
"""Returns the flags for the specified message."""
raise NotImplementedException
def savemessageflags(self, uid, flags):
"""Sets the specified message's flags to the given set."""
raise NotImplementedException
def addmessageflags(self, uid, flags):
"""Adds the specified flags to the message's flag set. If a given
flag is already present, it will not be duplicated."""
newflags = self.getmessageflags(uid)
for flag in flags:
if not flag in newflags:
newflags.append(flag)
newflags.sort()
self.savemessageflags(uid, newflags)
def addmessagesflags(self, uidlist, flags):
for uid in uidlist:
self.addmessageflags(uid, flags)
def deletemessageflags(self, uid, flags):
"""Removes each flag given from the message's flag set. If a given
flag is already removed, no action will be taken for that flag."""
newflags = self.getmessageflags(uid)
for flag in flags:
if flag in newflags:
newflags.remove(flag)
newflags.sort()
self.savemessageflags(uid, newflags)
def deletemessagesflags(self, uidlist, flags):
for uid in uidlist:
self.deletemessageflags(uid, flags)
def deletemessage(self, uid):
raise NotImplementedException
def deletemessages(self, uidlist):
for uid in uidlist:
self.deletemessage(uid)
def syncmessagesto_neguid_msg(self, uid, dest, applyto, register = 1):
if register:
self.ui.registerthread(self.getaccountname())
self.ui.copyingmessage(uid, self, applyto)
successobject = None
successuid = None
message = self.getmessage(uid)
flags = self.getmessageflags(uid)
rtime = self.getmessagetime(uid)
for tryappend in applyto:
successuid = tryappend.savemessage(uid, message, flags, rtime)
if successuid >= 0:
successobject = tryappend
break
# Did we succeed?
if successobject != None:
if successuid: # Only if IMAP actually assigned a UID
# Copy the message to the other remote servers.
for appendserver in \
[x for x in applyto if x != successobject]:
appendserver.savemessage(successuid, message, flags, rtime)
# Copy to its new name on the local server and delete
# the one without a UID.
self.savemessage(successuid, message, flags, rtime)
self.deletemessage(uid) # It'll be re-downloaded.
else:
# Did not find any server to take this message. Ignore.
pass
def syncmessagesto_neguid(self, dest, applyto):
"""Pass 1 of folder synchronization.
Look for messages in self with a negative uid. These are messages in
Maildirs that were not added by us. Try to add them to the dests,
and once that succeeds, get the UID, add it to the others for real,
add it to local for real, and delete the fake one."""
uidlist = [uid for uid in self.getmessagelist().keys() if uid < 0]
threads = []
usethread = None
if applyto != None:
usethread = applyto[0]
for uid in uidlist:
if usethread and usethread.suggeststhreads():
usethread.waitforthread()
thread = threadutil.InstanceLimitedThread(\
usethread.getcopyinstancelimit(),
target = self.syncmessagesto_neguid_msg,
name = "New msg sync from %s" % self.getvisiblename(),
args = (uid, dest, applyto))
thread.setDaemon(1)
thread.start()
threads.append(thread)
else:
self.syncmessagesto_neguid_msg(uid, dest, applyto, register = 0)
for thread in threads:
thread.join()
def copymessageto(self, uid, applyto, register = 1):
# Sometimes, it could be the case that if a sync takes awhile,
# a message might be deleted from the maildir before it can be
# synced to the status cache. This is only a problem with
# self.getmessage(). So, don't call self.getmessage unless
# really needed.
try:
if register:
self.ui.registerthread(self.getaccountname())
self.ui.copyingmessage(uid, self, applyto)
message = ''
# If any of the destinations actually stores the message body,
# load it up.
for object in applyto:
if object.storesmessages():
message = self.getmessage(uid)
break
flags = self.getmessageflags(uid)
rtime = self.getmessagetime(uid)
for object in applyto:
newuid = object.savemessage(uid, message, flags, rtime)
if newuid > 0 and newuid != uid:
# Change the local uid.
self.savemessage(newuid, message, flags, rtime)
self.deletemessage(uid)
uid = newuid
except (KeyboardInterrupt):
raise
except:
self.ui.warn("ERROR attempting to copy message " + str(uid) \
+ " for account " + self.getaccountname() + ":" + traceback.format_exc())
def syncmessagesto_copy(self, dest, applyto):
"""Pass 2 of folder synchronization.
Look for messages present in self but not in dest. If any, add
them to dest."""
threads = []
dest_messagelist = dest.getmessagelist()
for uid in self.getmessagelist().keys():
if uid < 0: # Ignore messages that pass 1 missed.
continue
if not uid in dest_messagelist:
if self.suggeststhreads():
self.waitforthread()
thread = threadutil.InstanceLimitedThread(\
self.getcopyinstancelimit(),
target = self.copymessageto,
name = "Copy message %d from %s" % (uid,
self.getvisiblename()),
args = (uid, applyto))
thread.setDaemon(1)
thread.start()
threads.append(thread)
else:
self.copymessageto(uid, applyto, register = 0)
for thread in threads:
thread.join()
def syncmessagesto_delete(self, dest, applyto):
"""Pass 3 of folder synchronization.
Look for message present in dest but not in self.
If any, delete them."""
deletelist = []
self_messagelist = self.getmessagelist()
for uid in dest.getmessagelist().keys():
if uid < 0:
continue
if not uid in self_messagelist:
deletelist.append(uid)
if len(deletelist):
self.ui.deletingmessages(deletelist, applyto)
for object in applyto:
object.deletemessages(deletelist)
def syncmessagesto_flags(self, dest, applyto):
"""Pass 4 of folder synchronization.
Look for any flag matching issues -- set dest message to have the
same flags that we have."""
# As an optimization over previous versions, we store up which flags
# are being used for an add or a delete. For each flag, we store
# a list of uids to which it should be added. Then, we can call
# addmessagesflags() to apply them in bulk, rather than one
# call per message as before. This should result in some significant
# performance improvements.
addflaglist = {}
delflaglist = {}
for uid in self.getmessagelist().keys():
if uid < 0: # Ignore messages missed by pass 1
continue
selfflags = self.getmessageflags(uid)
destflags = dest.getmessageflags(uid)
addflags = [x for x in selfflags if x not in destflags]
for flag in addflags:
if not flag in addflaglist:
addflaglist[flag] = []
addflaglist[flag].append(uid)
delflags = [x for x in destflags if x not in selfflags]
for flag in delflags:
if not flag in delflaglist:
delflaglist[flag] = []
delflaglist[flag].append(uid)
for object in applyto:
for flag in addflaglist.keys():
self.ui.addingflags(addflaglist[flag], flag, [object])
object.addmessagesflags(addflaglist[flag], [flag])
for flag in delflaglist.keys():
self.ui.deletingflags(delflaglist[flag], flag, [object])
object.deletemessagesflags(delflaglist[flag], [flag])
def syncmessagesto(self, dest, applyto = None):
"""Syncs messages in this folder to the destination.
If applyto is specified, it should be a list of folders (don't forget
to include dest!) to which all write actions should be applied.
It defaults to [dest] if not specified. It is important that
the UID generator be listed first in applyto; that is, the other
applyto ones should be the ones that "copy" the main action."""
if applyto == None:
applyto = [dest]
try:
self.syncmessagesto_neguid(dest, applyto)
except (KeyboardInterrupt):
raise
except:
self.ui.warn("ERROR attempting to handle negative uids " \
+ "for account " + self.getaccountname() + ":" + traceback.format_exc())
#all threads launched here are in try / except clauses when they copy anyway...
self.syncmessagesto_copy(dest, applyto)
try:
self.syncmessagesto_delete(dest, applyto)
except (KeyboardInterrupt):
raise
except:
self.ui.warn("ERROR attempting to delete messages " \
+ "for account " + self.getaccountname() + ":" + traceback.format_exc())
# Now, the message lists should be identical wrt the uids present.
# (except for potential negative uids that couldn't be placed
# anywhere)
try:
self.syncmessagesto_flags(dest, applyto)
except (KeyboardInterrupt):
raise
except:
self.ui.warn("ERROR attempting to sync flags " \
+ "for account " + self.getaccountname() + ":" + traceback.format_exc())