docker-offlineimap/offlineimap/folder/Maildir.py
Sebastian Spaeth f4081985dc Prettify and use new uidexists() helper function
Make the folder classes use uidexists() more. Add some code
documentation while going through.

Signed-off-by: Sebastian Spaeth <Sebastian@SSpaeth.de>
Signed-off-by: Nicolas Sebrecht <nicolas.s-dev@laposte.net>
2011-05-07 13:50:22 +02:00

319 lines
12 KiB
Python

# Maildir folder support
# Copyright (C) 2002 - 2007 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
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
uidmatchre = re.compile(',U=(\d+)')
flagmatchre = re.compile(':.*2,([A-Z]+)')
timestampmatchre = 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, accountname, config):
self.name = name
self.config = config
self.dofsync = config.getdefaultboolean("general", "fsync", True)
self.root = root
self.sep = sep
self.messagelist = None
self.repository = repository
self.accountname = accountname
BaseFolder.__init__(self)
#self.ui is set in BaseFolder.init()
def getaccountname(self):
return self.accountname
def getfullname(self):
return os.path.join(self.getroot(), self.getname())
def getuidvalidity(self):
"""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 = timestampmatchre.search(messagename)
timestampstr = timestampmatch.group()
timestamplong = long(timestampstr)
if(timestamplong < oldest_time_utc):
return False
else:
return True
def _scanfolder(self):
"""Cache the message list. Maildir flags are:
R (replied)
S (seen)
T (trashed)
D (draft)
F (flagged)
and must occur in ASCII order."""
retval = {}
files = []
nouidcounter = -1 # Messages without UIDs get
# negative UID numbers.
foldermd5 = md5(self.getvisiblename()).hexdigest()
folderstr = ',FMD5=' + foldermd5
for dirannex in ['new', 'cur']:
fulldirname = os.path.join(self.getfullname(), dirannex)
files.extend(os.path.join(fulldirname, filename) for
filename in os.listdir(fulldirname))
for file in files:
messagename = os.path.basename(file)
#check if there is a parameter for maxage / maxsize - then see if this
#message should be considered or not
maxage = self.config.getdefaultint("Account " + self.accountname, "maxage", -1)
maxsize = self.config.getdefaultint("Account " + self.accountname, "maxsize", -1)
if(maxage != -1):
isnewenough = self._iswithinmaxage(messagename, maxage)
if(isnewenough != True):
#this message is older than we should consider....
continue
#Check and see if the message is too big if the maxsize for this account is set
if(maxsize != -1):
filesize = os.path.getsize(file)
if(filesize > maxsize):
continue
foldermatch = messagename.find(folderstr) != -1
if not foldermatch:
# If there is no folder MD5 specified, or if it mismatches,
# assume it is a foreign (new) message and generate a
# negative uid for it
uid = nouidcounter
nouidcounter -= 1
else: # It comes from our folder.
uidmatch = uidmatchre.search(messagename)
uid = None
if not uidmatch:
uid = nouidcounter
nouidcounter -= 1
else:
uid = long(uidmatch.group(1))
flagmatch = flagmatchre.search(messagename)
flags = []
if flagmatch:
flags = [x for x in flagmatch.group(1)]
flags.sort()
retval[uid] = {'uid': uid,
'flags': flags,
'filename': file}
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):
filename = self.messagelist[uid]['filename']
file = open(filename, 'rt')
retval = file.read()
file.close()
return retval.replace("\r\n", "\n")
def getmessagetime( self, uid ):
filename = self.messagelist[uid]['filename']
st = os.stat(filename)
return st.st_mtime
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.
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 = None
attempts = 0
while 1:
if attempts > 15:
raise IOError, "Couldn't write to file %s" % messagename
timeval, timeseq = gettimeseq()
messagename = '%d_%d.%d.%s,U=%d,FMD5=%s' % \
(timeval,
timeseq,
os.getpid(),
socket.gethostname(),
uid,
md5(self.getvisiblename()).hexdigest())
if os.path.exists(os.path.join(tmpdir, messagename)):
time.sleep(2)
attempts += 1
else:
break
tmpmessagename = messagename.split(',')[0]
self.ui.debug('maildir', 'savemessage: using temporary name %s' % tmpmessagename)
file = open(os.path.join(tmpdir, tmpmessagename), "wt")
file.write(content)
# Make sure the data hits the disk
file.flush()
if self.dofsync:
os.fsync(file.fileno())
file.close()
if rtime != None:
os.utime(os.path.join(tmpdir,tmpmessagename), (rtime,rtime))
self.ui.debug('maildir', 'savemessage: moving from %s to %s' % \
(tmpmessagename, messagename))
if tmpmessagename != messagename: # then rename it
os.rename(os.path.join(tmpdir, tmpmessagename),
os.path.join(tmpdir, messagename))
if self.dofsync:
try:
# fsync the directory (safer semantics in Linux)
fd = os.open(tmpdir, os.O_RDONLY)
os.fsync(fd)
os.close(fd)
except:
pass
self.messagelist[uid] = {'uid': uid, 'flags': [],
'filename': os.path.join(tmpdir, messagename)}
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):
oldfilename = self.messagelist[uid]['filename']
newpath, newname = os.path.split(oldfilename)
tmpdir = os.path.join(self.getfullname(), 'tmp')
if 'S' in flags:
# If a message has been seen, it goes into the cur
# directory. CR debian#152482, [complete.org #4]
newpath = os.path.join(self.getfullname(), 'cur')
else:
newpath = os.path.join(self.getfullname(), 'new')
infostr = ':'
infomatch = re.search('(:.*)$', newname)
if infomatch: # If the info string is present..
infostr = infomatch.group(1)
newname = newname.split(':')[0] # Strip off the info string.
infostr = re.sub('2,[A-Z]*', '', infostr)
flags.sort()
infostr += '2,' + ''.join(flags)
newname += infostr
newfilename = os.path.join(newpath, newname)
if (newfilename != oldfilename):
os.rename(oldfilename, newfilename)
self.messagelist[uid]['flags'] = flags
self.messagelist[uid]['filename'] = newfilename
# By now, the message had better not be in tmp/ land!
final_dir, final_name = os.path.split(self.messagelist[uid]['filename'])
assert final_dir != tmpdir
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']
try:
os.unlink(filename)
except OSError:
# Can't find the file -- maybe already deleted?
newmsglist = self._scanfolder()
if uid in newmsglist: # Nope, try new filename.
os.unlink(newmsglist[uid]['filename'])
# Yep -- return.
del(self.messagelist[uid])