docker-offlineimap/offlineimap/folder/Maildir.py
Rodolfo García Peñas (kix) 6ec6111896 2to3 main
2020-08-28 03:32:43 +02:00

552 lines
23 KiB
Python

# Maildir folder support
# Copyright (C) 2002-2016 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
import six
from sys import exc_info
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, emailutil
from .Base import BaseFolder
# 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+)')
timehash = {}
timelock = Lock()
def _gettimeseq(date=None):
global timehash, timelock
timelock.acquire()
try:
if date is None:
date = int(time.time())
if date in timehash:
timehash[date] += 1
else:
timehash[date] = 0
return (date, timehash[date])
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.root = root
# 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())
# Modification time from 'Date' header.
utime_from_header_global = self.config.getdefaultboolean(
"general", "utime_from_header", False)
self._utime_from_header = self.config.getdefaultboolean(
self.repoconfname, "utime_from_header", utime_from_header_global)
# What do we substitute pathname separator in names (if any)
self.sep_subst = '-'
if os.path.sep == self.sep_subst:
self.sep_subst = '_'
# Interface from BaseFolder
def getfullname(self):
"""Return the absolute file path to the Maildir folder (sans cur|new)"""
return self._fullname
# Interface from BaseFolder
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
def _iswithintime(self, messagename, date):
"""Check to see if the given message is newer than date (a
time_struct) according to the maildir name which should begin
with a timestamp."""
timestampmatch = re_timestampmatch.search(messagename)
if not timestampmatch:
return True
timestampstr = timestampmatch.group()
timestamplong = int(timestampstr)
if(timestamplong < time.mktime(date)):
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
# XXX: This is wrong behaviour: if FMD5 is missing or mismatches, assume
# the mail is new and **fix UID to None** to avoid any conflict.
# XXX: If UID is missing, I have no idea what FMD5 can do. Should be
# fixed to None in this case, too.
if foldermatch:
uidmatch = re_uidmatch.search(filename)
if uidmatch:
uid = int(uidmatch.group(1))
flagmatch = self.re_flagmatch.search(filename)
if flagmatch:
flags = set((c for c in flagmatch.group(1)))
return prefix, uid, fmd5, flags
def _scanfolder(self, min_date=None, min_uid=None):
"""Cache the message list from a Maildir.
If min_date is set, this finds the min UID of all messages newer than
min_date and uses it as the real cutoff for considering messages.
This handles the edge cases where the date is much earlier than messages
with similar UID's (e.g. the UID was reassigned much later).
Maildir flags are:
D (draft) F (flagged) R (replied) S (seen) T (trashed),
plus lower-case letters for custom flags.
:returns: dict that can be used as self.messagelist.
"""
maxsize = self.getmaxsize()
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))
date_excludees = {}
for dirannex, filename in files:
if filename.startswith('.'):
continue # Ignore dot files.
# We store just dirannex and filename, ie 'cur/123...'
filepath = os.path.join(dirannex, filename)
# Check maxsize if this message should be considered.
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 = int(uidmatch.group(1))
if min_uid != None and uid > 0 and uid < min_uid:
continue
if min_date != None and not self._iswithintime(filename, min_date):
# Keep track of messages outside of the time limit, because they
# still might have UID > min(UIDs of within-min_date). We hit
# this case for maxage if any message had a known/valid datetime
# and was re-uploaded because the UID in the filename got lost
# (e.g. local copy/move). On next sync, it was assigned a new
# UID from the server and will be included in the SEARCH
# condition. So, we must re-include them later in this method
# in order to avoid inconsistent lists of messages.
date_excludees[uid] = self.msglist_item_initializer(uid)
date_excludees[uid]['flags'] = flags
date_excludees[uid]['filename'] = filepath
else:
# 'filename' is 'dirannex/filename', e.g. cur/123,U=1,FMD5=1:2,S
retval[uid] = self.msglist_item_initializer(uid)
retval[uid]['flags'] = flags
retval[uid]['filename'] = filepath
if min_date != None:
# Re-include messages with high enough uid's.
positive_uids = [uid for uid in retval if uid > 0]
if positive_uids:
min_uid = min(positive_uids)
for uid in list(date_excludees.keys()):
if uid > min_uid:
# This message was originally excluded because of
# its date. It is re-included now because we want all
# messages with UID > min_uid.
retval[uid] = date_excludees[uid]
return retval
# Interface from BaseFolder
def quickchanged(self, statusfolder):
"""Returns True if the Maildir has changed
Assumes cachemessagelist() has already been called """
# 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 list(self.getmessagelist().items()):
if message['flags'] != statusfolder.getmessageflags(uid):
return True
return False # Nope, nothing changed.
# Interface from BaseFolder
def msglist_item_initializer(self, uid):
return {'flags': set(), 'filename': '/no-dir/no-such-file/'}
# Interface from BaseFolder
def cachemessagelist(self, min_date=None, min_uid=None):
if self.ismessagelistempty():
self.ui.loadmessagelist(self.repository, self)
self.messagelist = self._scanfolder(min_date=min_date,
min_uid=min_uid)
self.ui.messagelistloaded(self.repository, self, self.getmessagecount())
# Interface from BaseFolder
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")
# Interface from BaseFolder
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(), date=None):
"""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(date)
uniq_name = '%d_%d.%d.%s,U=%d,FMD5=%s%s2,%s' % \
(timeval, timeseq, os.getpid(), socket.gethostname(),
uid, self._foldermd5, self.infosep, ''.join(sorted(flags)))
return uniq_name.replace(os.path.sep, self.sep_subst)
def save_to_tmp_file(self, filename, content):
"""Saves given content to the named temporary file in the
'tmp' subdirectory of $CWD.
Arguments:
- filename: name of the temporary file;
- content: data to be saved.
Returns: relative path to the temporary file
that was created."""
tmpname = os.path.join('tmp', filename)
# Open file and write it out.
# XXX: why do we need to loop 7 times?
tries = 7
while tries:
tries = tries - 1
try:
fd = os.open(os.path.join(self.getfullname(), tmpname),
os.O_EXCL|os.O_CREAT|os.O_WRONLY, 0o666)
break
except OSError as e:
if not hasattr(e, 'EEXIST'):
raise
if e.errno == e.EEXIST:
if tries:
time.sleep(0.23)
continue
severity = OfflineImapError.ERROR.MESSAGE
six.reraise(OfflineImapError,
OfflineImapError(
"Unique filename %s already exists."%
filename, severity),
exc_info()[2])
else:
raise
fd = os.fdopen(fd, 'wt')
fd.write(content)
# Make sure the data hits the disk.
fd.flush()
if self.dofsync():
os.fsync(fd)
fd.close()
return tmpname
# Interface from BaseFolder
def savemessage(self, uid, content, flags, rtime):
"""Writes a new message, with the specified uid.
See folder/Base for detail. Note that savemessage() does not
check against dryrun settings, so you need to ensure that
savemessage is never called in a dryrun mode."""
# This function only ever saves to tmp/,
# but it calls savemessageflags() to actually save to cur/ or new/.
self.ui.savemessage('maildir', uid, flags, self)
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')
# Use the mail timestamp given by either Date or Delivery-date mail
# headers.
message_timestamp = None
if self._filename_use_mail_timestamp is not False:
try:
message_timestamp = emailutil.get_message_date(content, 'Date')
if message_timestamp is None:
# Give a try with Delivery-date
message_timestamp = emailutil.get_message_date(
content, 'Delivery-date')
except Exception as e:
# This should never happen.
from email.Parser import Parser
from offlineimap.ui import getglobalui
datestr = Parser().parsestr(content, True).get("Date")
ui = getglobalui()
ui.warn("UID %d has invalid date %s: %s\n"
"Not using message timestamp as file prefix"%
(uid, datestr, e))
# No need to check if message_timestamp is None here since it
# would be overridden by _gettimeseq.
messagename = self.new_message_filename(uid, flags, date=message_timestamp)
tmpname = self.save_to_tmp_file(messagename, content)
if self._utime_from_header is True:
try:
date = emailutil.get_message_date(content, 'Date')
if date is not None:
os.utime(os.path.join(self.getfullname(), tmpname),
(date, date))
# In case date is wrongly so far into the future as to be > max
# int32.
except Exception as e:
from email.Parser import Parser
from offlineimap.ui import getglobalui
datestr = Parser().parsestr(content, True).get("Date")
ui = getglobalui()
ui.warn("UID %d has invalid date %s: %s\n"
"Not changing file modification time"% (uid, datestr, e))
self.messagelist[uid] = self.msglist_item_initializer(uid)
self.messagelist[uid]['flags'] = flags
self.messagelist[uid]['filename'] = tmpname
# savemessageflags moves msg to 'cur' or 'new' as appropriate.
self.savemessageflags(uid, flags)
self.ui.debug('maildir', 'savemessage: returning uid %d' % uid)
return uid
# Interface from BaseFolder
def getmessageflags(self, uid):
return self.messagelist[uid]['flags']
# Interface from BaseFolder
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.
Note that this function does not check against dryrun settings,
so you need to ensure that it is never called in a
dryrun mode."""
assert uid in self.messagelist
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
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 as e:
six.reraise(OfflineImapError,
OfflineImapError(
"Can't rename file '%s' to '%s': %s"%
(oldfilename, newfilename, e[1]),
OfflineImapError.ERROR.FOLDER),
exc_info()[2])
self.messagelist[uid]['flags'] = flags
self.messagelist[uid]['filename'] = newfilename
# Interface from BaseFolder
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,
OfflineImapError.ERROR.MESSAGE)
if uid == new_uid: return
oldfilename = self.messagelist[uid]['filename']
dir_prefix, filename = os.path.split(oldfilename)
flags = self.getmessageflags(uid)
# TODO: we aren't keeping the prefix timestamp so we don't honor the
# filename_use_mail_timestamp configuration option.
newfilename = os.path.join(dir_prefix,
self.new_message_filename(new_uid, flags))
os.rename(os.path.join(self.getfullname(), oldfilename),
os.path.join(self.getfullname(), newfilename))
self.messagelist[new_uid] = self.messagelist[uid]
self.messagelist[new_uid]['filename'] = newfilename
del self.messagelist[uid]
# Interface from BaseFolder
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.
"""
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])
def migratefmd5(self, dryrun=False):
"""Migrate FMD5 hashes from versions prior to 6.3.5
:param dryrun: Run in dry run mode
:type fix: Boolean
:return: None
"""
oldfmd5 = md5(self.name).hexdigest()
msglist = self._scanfolder()
for mkey, mvalue in list(msglist.items()):
filename = os.path.join(self.getfullname(), mvalue['filename'])
match = re.search("FMD5=([a-fA-F0-9]+)", filename)
if match is None:
self.ui.debug("maildir",
"File `%s' doesn't have an FMD5 assigned"
% filename)
elif match.group(1) == oldfmd5:
self.ui.info("Migrating file `%s' to FMD5 `%s'"
% (filename, self._foldermd5))
if not dryrun:
newfilename = filename.replace(
"FMD5=" + match.group(1), "FMD5=" + self._foldermd5)
try:
os.rename(filename, newfilename)
except OSError as e:
six.reraise(OfflineImapError,
OfflineImapError(
"Can't rename file '%s' to '%s': %s"%
(filename, newfilename, e[1]),
OfflineImapError.ERROR.FOLDER),
exc_info()[2])
elif match.group(1) != self._foldermd5:
self.ui.warn(("Inconsistent FMD5 for file `%s':"
" Neither `%s' nor `%s' found")
% (filename, oldfmd5, self._foldermd5))