docker-offlineimap/offlineimap/folder/Maildir.py
Sebastian Spaeth 9453e1d955 Fix getuidvalidity crash (UIDVALIDITY returning None)
Rename getuidvalidity -> get_uidvalidity and cache the IMAP result.

1) Start modernizing our function names using more underscores
2) IMAPs implementation of get_uidvalidity was removing the UIDVALIDITY result
   from the imaplib2 result stack, so subsequent calls would return "None".
   As various functions can invoke this, this led to some errors that we
   avoid by caching the current UIDVALIDITY value in the Folder instance.

There are more simplifications and improvements to be made.

Signed-off-by: Sebastian Spaeth <Sebastian@SSpaeth.de>
2012-01-19 12:02:13 +01:00

369 lines
15 KiB
Python

# Maildir folder support
# Copyright (C) 2002 - 2011 John Goerzen & 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 socket
import time
import re
import os
from Base import BaseFolder
from threading import Lock
try:
from hashlib import md5
except ImportError:
from md5 import md5
try: # python 2.6 has set() built in
set
except NameError:
from sets import Set as set
from offlineimap import OfflineImapError
# Find the UID in a message filename
re_uidmatch = re.compile(',U=(\d+)')
# Find a numeric timestamp in a string (filename prefix)
re_timestampmatch = re.compile('(\d+)');
timeseq = 0
lasttime = long(0)
timelock = Lock()
def gettimeseq():
global lasttime, timeseq, timelock
timelock.acquire()
try:
thistime = long(time.time())
if thistime == lasttime:
timeseq += 1
return (thistime, timeseq)
else:
lasttime = thistime
timeseq = 0
return (thistime, timeseq)
finally:
timelock.release()
class MaildirFolder(BaseFolder):
def __init__(self, root, name, sep, repository):
self.sep = sep # needs to be set before super().__init__
super(MaildirFolder, self).__init__(name, repository)
self.dofsync = self.config.getdefaultboolean("general", "fsync", True)
self.root = root
self.messagelist = None
# check if we should use a different infosep to support Win file systems
self.wincompatible = self.config.getdefaultboolean(
"Account "+self.accountname, "maildir-windows-compatible", False)
self.infosep = '!' if self.wincompatible else ':'
"""infosep is the separator between maildir name and flag appendix"""
self.re_flagmatch = re.compile('%s2,(\w*)' % self.infosep)
#self.ui is set in BaseFolder.init()
# Everything up to the first comma or colon (or ! if Windows):
self.re_prefixmatch = re.compile('([^'+ self.infosep + ',]*)')
#folder's md, so we can match with recorded file md5 for validity
self._foldermd5 = md5(self.getvisiblename()).hexdigest()
# Cache the full folder path, as we use getfullname() very often
self._fullname = os.path.join(self.getroot(), self.getname())
def getfullname(self):
"""Return the absolute file path to the Maildir folder (sans cur|new)"""
return self._fullname
def get_uidvalidity(self):
"""Retrieve the current connections UIDVALIDITY value
Maildirs have no notion of uidvalidity, so we just return a magic
token."""
return 42
#Checks to see if the given message is within the maximum age according
#to the maildir name which should begin with a timestamp
def _iswithinmaxage(self, messagename, maxage):
#In order to have the same behaviour as SINCE in an IMAP search
#we must convert this to the oldest time and then strip off hrs/mins
#from that day
oldest_time_utc = time.time() - (60*60*24*maxage)
oldest_time_struct = time.gmtime(oldest_time_utc)
oldest_time_today_seconds = ((oldest_time_struct[3] * 3600) \
+ (oldest_time_struct[4] * 60) \
+ oldest_time_struct[5])
oldest_time_utc -= oldest_time_today_seconds
timestampmatch = re_timestampmatch.search(messagename)
timestampstr = timestampmatch.group()
timestamplong = long(timestampstr)
if(timestamplong < oldest_time_utc):
return False
else:
return True
def _parse_filename(self, filename):
"""Returns a messages file name components
Receives the file name (without path) of a msg. Usual format is
'<%d_%d.%d.%s>,U=<%d>,FMD5=<%s>:2,<FLAGS>' (pointy brackets
denoting the various components).
If FMD5 does not correspond with the current folder MD5, we will
return None for the UID & FMD5 (as it is not valid in this
folder). If UID or FMD5 can not be detected, we return `None`
for the respective element. If flags are empty or cannot be
detected, we return an empty flags list.
:returns: (prefix, UID, FMD5, flags). UID is a numeric "long"
type. flags is a set() of Maildir flags"""
prefix, uid, fmd5, flags = None, None, None, set()
prefixmatch = self.re_prefixmatch.match(filename)
if prefixmatch:
prefix = prefixmatch.group(1)
folderstr = ',FMD5=%s' % self._foldermd5
foldermatch = folderstr in filename
# If there was no folder MD5 specified, or if it mismatches,
# assume it is a foreign (new) message and ret: uid, fmd5 = None, None
if foldermatch:
uidmatch = re_uidmatch.search(filename)
if uidmatch:
uid = long(uidmatch.group(1))
flagmatch = self.re_flagmatch.search(filename)
if flagmatch:
# Filter out all lowercase (custom maildir) flags. We don't
# handle them yet.
flags = set((c for c in flagmatch.group(1) if not c.islower()))
return prefix, uid, fmd5, flags
def _scanfolder(self):
"""Cache the message list from a Maildir.
Maildir flags are: R (replied) S (seen) T (trashed) D (draft) F
(flagged).
:returns: dict that can be used as self.messagelist"""
maxage = self.config.getdefaultint("Account " + self.accountname,
"maxage", None)
maxsize = self.config.getdefaultint("Account " + self.accountname,
"maxsize", None)
retval = {}
files = []
nouidcounter = -1 # Messages without UIDs get negative UIDs.
for dirannex in ['new', 'cur']:
fulldirname = os.path.join(self.getfullname(), dirannex)
files.extend((dirannex, filename) for
filename in os.listdir(fulldirname))
for dirannex, filename in files:
# We store just dirannex and filename, ie 'cur/123...'
filepath = os.path.join(dirannex, filename)
# check maxage/maxsize if this message should be considered
if maxage and not self._iswithinmaxage(filename, maxage):
continue
if maxsize and (os.path.getsize(os.path.join(
self.getfullname(), filepath)) > maxsize):
continue
(prefix, uid, fmd5, flags) = self._parse_filename(filename)
if uid is None: # assign negative uid to upload it.
uid = nouidcounter
nouidcounter -= 1
else: # It comes from our folder.
uidmatch = re_uidmatch.search(filename)
uid = None
if not uidmatch:
uid = nouidcounter
nouidcounter -= 1
else:
uid = long(uidmatch.group(1))
# 'filename' is 'dirannex/filename', e.g. cur/123,U=1,FMD5=1:2,S
retval[uid] = {'flags': flags, 'filename': filepath}
return retval
def quickchanged(self, statusfolder):
"""Returns True if the Maildir has changed"""
self.cachemessagelist()
# Folder has different uids than statusfolder => TRUE
if sorted(self.getmessageuidlist()) != \
sorted(statusfolder.getmessageuidlist()):
return True
# Also check for flag changes, it's quick on a Maildir
for (uid, message) in self.getmessagelist().iteritems():
if message['flags'] != statusfolder.getmessageflags(uid):
return True
return False #Nope, nothing changed
def cachemessagelist(self):
if self.messagelist is None:
self.messagelist = self._scanfolder()
def getmessagelist(self):
return self.messagelist
def getmessage(self, uid):
"""Return the content of the message"""
filename = self.messagelist[uid]['filename']
filepath = os.path.join(self.getfullname(), filename)
file = open(filepath, 'rt')
retval = file.read()
file.close()
#TODO: WHY are we replacing \r\n with \n here? And why do we
# read it as text?
return retval.replace("\r\n", "\n")
def getmessagetime(self, uid):
filename = self.messagelist[uid]['filename']
filepath = os.path.join(self.getfullname(), filename)
return os.path.getmtime(filepath)
def new_message_filename(self, uid, flags=set()):
"""Creates a new unique Maildir filename
:param uid: The UID`None`, or a set of maildir flags
:param flags: A set of maildir flags
:returns: String containing unique message filename"""
timeval, timeseq = gettimeseq()
return '%d_%d.%d.%s,U=%d,FMD5=%s%s2,%s' % \
(timeval, timeseq, os.getpid(), socket.gethostname(),
uid, self._foldermd5, self.infosep, ''.join(sorted(flags)))
def savemessage(self, uid, content, flags, rtime):
# This function only ever saves to tmp/,
# but it calls savemessageflags() to actually save to cur/ or new/.
self.ui.debug('maildir', 'savemessage: called to write with flags %s '
'and content %s' % (repr(flags), repr(content)))
if uid < 0:
# We cannot assign a new uid.
return uid
if uid in self.messagelist:
# We already have it, just update flags.
self.savemessageflags(uid, flags)
return uid
# Otherwise, save the message in tmp/ and then call savemessageflags()
# to give it a permanent home.
tmpdir = os.path.join(self.getfullname(), 'tmp')
messagename = self.new_message_filename(uid, flags)
# open file and write it out
try:
fd = os.open(os.path.join(tmpdir, messagename),
os.O_EXCL|os.O_CREAT|os.O_WRONLY, 0666)
except OSError, e:
if e.errno == 17:
#FILE EXISTS ALREADY
severity = OfflineImapError.ERROR.MESSAGE
raise OfflineImapError("Unique filename %s already existing." %\
messagename, severity)
else:
raise
file = os.fdopen(fd, 'wt')
file.write(content)
# Make sure the data hits the disk
file.flush()
if self.dofsync:
os.fsync(fd)
file.close()
if rtime != None:
os.utime(os.path.join(tmpdir, messagename), (rtime, rtime))
self.messagelist[uid] = {'flags': flags,
'filename': os.path.join('tmp', messagename)}
# savemessageflags moves msg to 'cur' or 'new' as appropriate
self.savemessageflags(uid, flags)
self.ui.debug('maildir', 'savemessage: returning uid %d' % uid)
return uid
def getmessageflags(self, uid):
return self.messagelist[uid]['flags']
def savemessageflags(self, uid, flags):
"""Sets the specified message's flags to the given set.
This function moves the message to the cur or new subdir,
depending on the 'S'een flag."""
oldfilename = self.messagelist[uid]['filename']
dir_prefix, filename = os.path.split(oldfilename)
# If a message has been seen, it goes into 'cur'
dir_prefix = 'cur' if 'S' in flags else 'new'
if flags != self.messagelist[uid]['flags']:
# Flags have actually changed, construct new filename Strip
# off existing infostring (possibly discarding small letter
# flags that dovecot uses TODO)
infomatch = self.re_flagmatch.search(filename)
if infomatch:
filename = filename[:-len(infomatch.group())] #strip off
infostr = '%s2,%s' % (self.infosep, ''.join(sorted(flags)))
filename += infostr
newfilename = os.path.join(dir_prefix, filename)
if (newfilename != oldfilename):
try:
os.rename(os.path.join(self.getfullname(), oldfilename),
os.path.join(self.getfullname(), newfilename))
except OSError, e:
raise OfflineImapError("Can't rename file '%s' to '%s': %s" % (
oldfilename, newfilename, e[1]),
OfflineImapError.ERROR.FOLDER)
self.messagelist[uid]['flags'] = flags
self.messagelist[uid]['filename'] = newfilename
def change_message_uid(self, uid, new_uid):
"""Change the message from existing uid to new_uid
This will not update the statusfolder UID, you need to do that yourself.
:param new_uid: (optional) If given, the old UID will be changed
to a new UID. The Maildir backend can implement this as an efficient
rename."""
if not uid in self.messagelist:
raise OfflineImapError("Cannot change unknown Maildir UID %s" % uid)
if uid == new_uid: return
oldfilename = self.messagelist[uid]['filename']
dir_prefix, filename = os.path.split(oldfilename)
flags = self.getmessageflags(uid)
filename = self.new_message_filename(new_uid, flags)
os.rename(os.path.join(self.getfullname(), oldfilename),
os.path.join(self.getfullname(), dir_prefix, filename))
self.messagelist[new_uid] = self.messagelist[uid]
del self.messagelist[uid]
def deletemessage(self, uid):
"""Unlinks a message file from the Maildir.
:param uid: UID of a mail message
:type uid: String
:return: Nothing, or an Exception if UID but no corresponding file
found.
"""
if not self.uidexists(uid):
return
filename = self.messagelist[uid]['filename']
filepath = os.path.join(self.getfullname(), filename)
try:
os.unlink(filepath)
except OSError:
# Can't find the file -- maybe already deleted?
newmsglist = self._scanfolder()
if uid in newmsglist: # Nope, try new filename.
filename = newmsglist[uid]['filename']
filepath = os.path.join(self.getfullname(), filename)
os.unlink(filepath)
# Yep -- return.
del(self.messagelist[uid])