# Base 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 from offlineimap import threadutil, emailutil from offlineimap import globals from offlineimap.ui import getglobalui from offlineimap.error import OfflineImapError import offlineimap.accounts import os.path import re from sys import exc_info import traceback class BaseFolder(object): def __init__(self, name, repository): """ :para name: Path & name of folder minus root or reference :para repository: Repository() in which the folder is. """ self.ui = getglobalui() # Save original name for folderfilter operations self.ffilter_name = name # Top level dir name is always '' self.root = None self.name = name if not name == self.getsep() else '' self.repository = repository self.visiblename = repository.nametrans(name) # In case the visiblename becomes '.' or '/' (top-level) we use # '' as that is the name that e.g. the Maildir scanning will # return for the top-level dir. if self.visiblename == self.getsep(): self.visiblename = '' self.config = repository.getconfig() utime_from_message_global = \ self.config.getdefaultboolean("general", "utime_from_message", False) repo = "Repository " + repository.name self._utime_from_message = \ self.config.getdefaultboolean(repo, "utime_from_message", utime_from_message_global) # Determine if we're running static or dynamic folder filtering # and check filtering status self._dynamic_folderfilter = \ self.config.getdefaultboolean(repo, "dynamic_folderfilter", False) self._sync_this = repository.should_sync_folder(self.ffilter_name) if self._dynamic_folderfilter: self.ui.debug('', "Running dynamic folder filtering on '%s'[%s]" \ % (self.ffilter_name, repository)) elif not self._sync_this: self.ui.debug('', "Filtering out '%s'[%s] due to folderfilter" \ % (self.ffilter_name, repository)) # Passes for syncmessagesto self.syncmessagesto_passes = [('copying messages' , self.__syncmessagesto_copy), ('deleting messages' , self.__syncmessagesto_delete), ('syncing flags' , self.__syncmessagesto_flags)] def getname(self): """Returns name""" return self.name def __str__(self): return self.name @property def accountname(self): """Account name as string""" return self.repository.accountname @property def sync_this(self): """Should this folder be synced or is it e.g. filtered out?""" if not self._dynamic_folderfilter: return self._sync_this else: return self.repository.should_sync_folder(self.ffilter_name) @property def utime_from_message(self): return self._utime_from_message 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): """Implements method that waits for thread to be usable. Should be implemented only for folders that suggest threads.""" raise NotImplementedError # XXX: we may need someting like supports_quickstatus() to check # XXX: if user specifies 'quick' flag for folder that doesn't # XXX: support quick status queries, so one believes that quick # XXX: status checks will be done, but it won't really be so. def quickchanged(self, statusfolder): """ Runs quick check for folder changes and returns changed status: True -- changed, False -- not changed. :param statusfolder: keeps track of the last known folder state. """ return True def getcopyinstancelimit(self): """For threading folders, returns the instancelimitname for InstanceLimitedThreads.""" raise NotImplementedError 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): """The nametrans-transposed name of the folder's name""" return self.visiblename def getexplainedname(self): """ Name that shows both real and nametrans-mangled values""" if self.name == self.visiblename: return self.name else: return "%s [remote name %s]" % (self.visiblename, 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): """Return base file name of file to store Status/UID info in""" if not self.name: basename = '.' else: #avoid directory hierarchies and file names such as '/' basename = self.name.replace('/', '.') # replace with literal 'dot' if final path name is '.' as '.' is # an invalid file name. basename = re.sub('(^|\/)\.$','\\1dot', basename) return basename def check_uidvalidity(self): """Tests if the cached UIDVALIDITY match the real current one If required it saves the UIDVALIDITY value. In this case the function is not threadsafe. So don't attempt to call it from concurrent threads. :returns: Boolean indicating the match. Returns True in case it implicitely saved the UIDVALIDITY.""" if self.get_saveduidvalidity() != None: return self.get_saveduidvalidity() == self.get_uidvalidity() else: self.save_uidvalidity() return True def _getuidfilename(self): """provides UIDVALIDITY cache filename for class internal purposes""" return os.path.join(self.repository.getuiddir(), self.getfolderbasename()) def get_saveduidvalidity(self): """Return the previously cached UIDVALIDITY value :returns: UIDVALIDITY as (long) number or None, if None had been saved yet.""" 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 save_uidvalidity(self): """Save the UIDVALIDITY value of the folder to the cache This function is not threadsafe, so don't attempt to call it from concurrent threads.""" newval = self.get_uidvalidity() uidfilename = self._getuidfilename() with open(uidfilename + ".tmp", "wt") as file: file.write("%d\n" % newval) os.rename(uidfilename + ".tmp", uidfilename) self._base_saved_uidvalidity = newval def get_uidvalidity(self): """Retrieve the current connections UIDVALIDITY value This function needs to be implemented by each Backend :returns: UIDVALIDITY as a (long) number""" raise NotImplementedError 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 NotImplementedError def getmessagelist(self): """Gets the current message list. You must call cachemessagelist() before calling this function!""" raise NotImplementedError def uidexists(self, uid): """Returns True if uid exists""" return uid in self.getmessagelist() def getmessageuidlist(self): """Gets a list of UIDs. You may have to call cachemessagelist() before calling this function!""" return self.getmessagelist().keys() def getmessagecount(self): """Gets the number of messages.""" return len(self.getmessagelist()) def getmessage(self, uid): """Returns the content of the specified message.""" raise NotImplementedError 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. In case it cannot assign a new uid, it returns the negative 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 some 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. Note that savemessage() does not check against dryrun settings, so you need to ensure that savemessage is never called in a dryrun mode. """ raise NotImplementedError def getmessagetime(self, uid): """Return the received time for the specified message.""" raise NotImplementedError def getmessagemtime(self, uid): """Returns the message modification time of the specified message.""" raise NotImplementedError def getmessageflags(self, uid): """Returns the flags for the specified message.""" raise NotImplementedError def savemessageflags(self, uid, flags): """Sets the specified message's flags to the given set. Note that this function does not check against dryrun settings, so you need to ensure that it is never called in a dryrun mode.""" raise NotImplementedError 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. Note that this function does not check against dryrun settings, so you need to ensure that it is never called in a dryrun mode. :param flags: A set() of flags""" newflags = self.getmessageflags(uid) | flags self.savemessageflags(uid, newflags) def addmessagesflags(self, uidlist, flags): """ Note that this function does not check against dryrun settings, so you need to ensure that it is never called in a dryrun mode.""" 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. Note that this function does not check against dryrun settings, so you need to ensure that it is never called in a dryrun mode.""" newflags = self.getmessageflags(uid) - flags self.savemessageflags(uid, newflags) def deletemessagesflags(self, uidlist, flags): """ Note that this function does not check against dryrun settings, so you need to ensure that it is never called in a dryrun mode.""" for uid in uidlist: self.deletemessageflags(uid, flags) def getmessagelabels(self, uid): """Returns the labels for the specified message.""" raise NotImplementedError def savemessagelabels(self, uid, labels, ignorelabels=set(), mtime=0): """Sets the specified message's labels to the given set. Note that this function does not check against dryrun settings, so you need to ensure that it is never called in a dryrun mode.""" raise NotImplementedError def addmessagelabels(self, uid, labels): """Adds the specified labels to the message's labels set. If a given label is already present, it will not be duplicated. Note that this function does not check against dryrun settings, so you need to ensure that it is never called in a dryrun mode. :param labels: A set() of labels""" newlabels = self.getmessagelabels(uid) | labels self.savemessagelabels(uid, newlabels) def addmessageslabels(self, uidlist, labels): """ Note that this function does not check against dryrun settings, so you need to ensure that it is never called in a dryrun mode.""" for uid in uidlist: self.addmessagelabels(uid, labels) def deletemessagelabels(self, uid, labels): """Removes each label given from the message's label set. If a given label is already removed, no action will be taken for that label. Note that this function does not check against dryrun settings, so you need to ensure that it is never called in a dryrun mode.""" newlabels = self.getmessagelabels(uid) - labels self.savemessagelabels(uid, newlabels) def deletemessageslabels(self, uidlist, labels): """ Note that this function does not check against dryrun settings, so you need to ensure that it is never called in a dryrun mode.""" for uid in uidlist: self.deletemessagelabels(uid, labels) def addmessageheader(self, content, linebreak, headername, headervalue): """ Adds new header to the provided message. Arguments: - content: message content, headers and body as a single string - linebreak: string that carries line ending - headername: name of the header to add - headervalue: value of the header to add This has to deal with strange corner cases where the header is missing or empty. Here are illustrations for all the cases, showing where the header gets inserted and what the end result is. In each illustration, '+' means the added contents. Note that these examples assume LF for linebreak, not CRLF, so '\n' denotes a linebreak and '\n\n' corresponds to the transition between header and body. However if the linebreak parameter is set to '\r\n' then you would have to substitute '\r\n' for '\n' in the below examples. * Case 1: No '\n\n', leading '\n' +X-Flying-Pig-Header: i am here\n \n This is the body\n next line\n * Case 2: '\n\n' at position 0 +X-Flying-Pig-Header: i am here \n \n This is the body\n next line\n * Case 3: No '\n\n', no leading '\n' +X-Flying-Pig-Header: i am here\n +\n This is the body\n next line\n * Case 4: '\n\n' at non-zero position Subject: Something wrong with OI\n From: some@person.at +\nX-Flying-Pig-Header: i am here \n \n This is the body\n next line\n """ self.ui.debug('', 'addmessageheader: called to add %s: %s' % (headername, headervalue)) insertionpoint = content.find(linebreak * 2) if insertionpoint == -1: self.ui.debug('', 'addmessageheader: headers were missing') else: self.ui.debug('', 'addmessageheader: headers end at position %d' % insertionpoint) mark = '==>EOH<==' contextstart = max(0, insertionpoint - 100) contextend = min(len(content), insertionpoint + 100) self.ui.debug('', 'addmessageheader: header/body transition context (marked by %s): %s' % (mark, repr(content[contextstart:insertionpoint]) + \ mark + repr(content[insertionpoint:contextend]))) # Hoping for case #4 prefix = linebreak suffix = '' # Case #2 if insertionpoint == 0: prefix = '' suffix = '' # Either case #1 or #3 elif insertionpoint == -1: prefix = '' suffix = linebreak insertionpoint = 0 # Case #3: when body starts immediately, without preceding '\n' # (this shouldn't happen with proper mail messages, but # we seen many broken ones), we should add '\n' to make # new (and the only header, in this case) to be properly # separated from the message body. if content[0:len(linebreak)] != linebreak: suffix = suffix + linebreak self.ui.debug('', 'addmessageheader: insertionpoint = %d' % insertionpoint) headers = content[0:insertionpoint] self.ui.debug('', 'addmessageheader: headers = %s' % repr(headers)) new_header = prefix + ("%s: %s" % (headername, headervalue)) + suffix self.ui.debug('', 'addmessageheader: new_header = ' + repr(new_header)) return headers + new_header + content[insertionpoint:] def __find_eoh(self, content): """ Searches for the point where mail headers end. Either double '\n', or end of string. Arguments: - content: contents of the message to search in Returns: position of the first non-header byte. """ eoh_cr = content.find('\n\n') if eoh_cr == -1: eoh_cr = len(content) return eoh_cr def getmessageheader(self, content, name): """ Searches for the given header and returns its value. Header name is case-insensitive. Arguments: - contents: message itself - name: name of the header to be searched Returns: header value or None if no such header was found """ self.ui.debug('', 'getmessageheader: called to get %s' % name) eoh = self.__find_eoh(content) self.ui.debug('', 'getmessageheader: eoh = %d' % eoh) headers = content[0:eoh] self.ui.debug('', 'getmessageheader: headers = %s' % repr(headers)) m = re.search('^%s:(.*)$' % name, headers, flags = re.MULTILINE | re.IGNORECASE) if m: return m.group(1).strip() else: return None def deletemessageheaders(self, content, header_list): """ Deletes headers in the given list from the message content. Arguments: - content: message itself - header_list: list of headers to be deleted or just the header name We expect our message to have '\n' as line endings. """ if type(header_list) != type([]): header_list = [header_list] self.ui.debug('', 'deletemessageheaders: called to delete %s' % (header_list)) if not len(header_list): return content eoh = self.__find_eoh(content) self.ui.debug('', 'deletemessageheaders: end of headers = %d' % eoh) headers = content[0:eoh] rest = content[eoh:] self.ui.debug('', 'deletemessageheaders: headers = %s' % repr(headers)) new_headers = [] for h in headers.split('\n'): keep_it = True for trim_h in header_list: if len(h) > len(trim_h) and h[0:len(trim_h)+1] == (trim_h + ":"): keep_it = False break if keep_it: new_headers.append(h) return ('\n'.join(new_headers) + rest) def change_message_uid(self, uid, new_uid): """Change the message from existing uid to new_uid If the backend supports it (IMAP does not). :param new_uid: (optional) If given, the old UID will be changed to a new UID. This allows backends efficient renaming of messages if the UID has changed.""" raise NotImplementedError def deletemessage(self, uid): """ Note that this function does not check against dryrun settings, so you need to ensure that it is never called in a dryrun mode.""" raise NotImplementedError def deletemessages(self, uidlist): """ Note that this function does not check against dryrun settings, so you need to ensure that it is never called in a dryrun mode.""" for uid in uidlist: self.deletemessage(uid) def copymessageto(self, uid, dstfolder, statusfolder, register = 1): """Copies a message from self to dst if needed, updating the status Note that this function does not check against dryrun settings, so you need to ensure that it is never called in a dryrun mode. :param uid: uid of the message to be copied. :param dstfolder: A BaseFolder-derived instance :param statusfolder: A LocalStatusFolder instance :param register: whether we should register a new thread." :returns: Nothing on success, or raises an Exception.""" # 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. if register: # output that we start a new thread self.ui.registerthread(self.repository.account) try: message = None flags = self.getmessageflags(uid) rtime = self.getmessagetime(uid) if dstfolder.utime_from_message: content = self.getmessage(uid) rtime = emailutil.get_message_date(content, 'Date') if uid > 0 and dstfolder.uidexists(uid): # dst has message with that UID already, only update status statusfolder.savemessage(uid, None, flags, rtime) return # If any of the destinations actually stores the message body, # load it up. if dstfolder.storesmessages(): message = self.getmessage(uid) #Succeeded? -> IMAP actually assigned a UID. If newid #remained negative, no server was willing to assign us an #UID. If newid is 0, saving succeeded, but we could not #retrieve the new UID. Ignore message in this case. new_uid = dstfolder.savemessage(uid, message, flags, rtime) if new_uid > 0: if new_uid != uid: # Got new UID, change the local uid to match the new one. self.change_message_uid(uid, new_uid) statusfolder.deletemessage(uid) # Got new UID, change the local uid. # Save uploaded status in the statusfolder statusfolder.savemessage(new_uid, message, flags, rtime) elif new_uid == 0: # Message was stored to dstfolder, but we can't find it's UID # This means we can't link current message to the one created # in IMAP. So we just delete local message and on next run # we'll sync it back # XXX This could cause infinite loop on syncing between two # IMAP servers ... self.deletemessage(uid) else: raise OfflineImapError("Trying to save msg (uid %d) on folder " "%s returned invalid uid %d" % (uid, dstfolder.getvisiblename(), new_uid), OfflineImapError.ERROR.MESSAGE) except (KeyboardInterrupt): # bubble up CTRL-C raise except OfflineImapError as e: if e.severity > OfflineImapError.ERROR.MESSAGE: raise # bubble severe errors up self.ui.error(e, exc_info()[2]) except Exception as e: self.ui.error(e, exc_info()[2], msg="Copying message %s [acc: %s]" %\ (uid, self.accountname)) raise #raise on unknown errors, so we can fix those def __syncmessagesto_copy(self, dstfolder, statusfolder): """Pass1: Copy locally existing messages not on the other side This will copy messages to dstfolder that exist locally but are not in the statusfolder yet. The strategy is: 1) Look for messages present in self but not in statusfolder. 2) invoke copymessageto() on those which: - If dstfolder doesn't have it yet, add them to dstfolder. - Update statusfolder This function checks and protects us from action in ryrun mode. """ threads = [] copylist = filter(lambda uid: not \ statusfolder.uidexists(uid), self.getmessageuidlist()) num_to_copy = len(copylist) if num_to_copy and self.repository.account.dryrun: self.ui.info("[DRYRUN] Copy {0} messages from {1}[{2}] to {3}".format( num_to_copy, self, self.repository, dstfolder.repository)) return for num, uid in enumerate(copylist): # bail out on CTRL-C or SIGTERM if offlineimap.accounts.Account.abort_NOW_signal.is_set(): break self.ui.copyingmessage(uid, num+1, num_to_copy, self, dstfolder) # exceptions are caught in copymessageto() if self.suggeststhreads() and not globals.options.singlethreading: self.waitforthread() thread = threadutil.InstanceLimitedThread(\ self.getcopyinstancelimit(), target = self.copymessageto, name = "Copy message from %s:%s" % (self.repository, self), args = (uid, dstfolder, statusfolder)) thread.start() threads.append(thread) else: self.copymessageto(uid, dstfolder, statusfolder, register = 0) for thread in threads: thread.join() def __syncmessagesto_delete(self, dstfolder, statusfolder): """Pass 2: Remove locally deleted messages on dst Get all UIDS in statusfolder but not self. These are messages that were deleted in 'self'. Delete those from dstfolder and statusfolder. This function checks and protects us from action in ryrun mode. """ deletelist = filter(lambda uid: uid>=0 \ and not self.uidexists(uid), statusfolder.getmessageuidlist()) if len(deletelist): self.ui.deletingmessages(deletelist, [dstfolder]) if self.repository.account.dryrun: return #don't delete messages in dry-run mode # delete in statusfolder first to play safe. In case of abort, we # won't lose message, we will just retransmit some unneccessary. for folder in [statusfolder, dstfolder]: folder.deletemessages(deletelist) def __syncmessagesto_flags(self, dstfolder, statusfolder): """Pass 3: Flag synchronization Compare flag mismatches in self with those in statusfolder. If msg has a valid UID and exists on dstfolder (has not e.g. been deleted there), sync the flag change to both dstfolder and statusfolder. This function checks and protects us from action in ryrun mode. """ # 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. addflaglist = {} delflaglist = {} for uid in self.getmessageuidlist(): # Ignore messages with negative UIDs missed by pass 1 and # don't do anything if the message has been deleted remotely if uid < 0 or not dstfolder.uidexists(uid): continue selfflags = self.getmessageflags(uid) if statusfolder.uidexists(uid): statusflags = statusfolder.getmessageflags(uid) else: statusflags = set() addflags = selfflags - statusflags delflags = statusflags - selfflags for flag in addflags: if not flag in addflaglist: addflaglist[flag] = [] addflaglist[flag].append(uid) for flag in delflags: if not flag in delflaglist: delflaglist[flag] = [] delflaglist[flag].append(uid) for flag, uids in addflaglist.items(): self.ui.addingflags(uids, flag, dstfolder) if self.repository.account.dryrun: continue #don't actually add in a dryrun dstfolder.addmessagesflags(uids, set(flag)) statusfolder.addmessagesflags(uids, set(flag)) for flag,uids in delflaglist.items(): self.ui.deletingflags(uids, flag, dstfolder) if self.repository.account.dryrun: continue #don't actually remove in a dryrun dstfolder.deletemessagesflags(uids, set(flag)) statusfolder.deletemessagesflags(uids, set(flag)) def syncmessagesto(self, dstfolder, statusfolder): """Syncs messages in this folder to the destination dstfolder. This is the high level entry for syncing messages in one direction. Syncsteps are: Pass1: Copy locally existing messages Copy messages in self, but not statusfolder to dstfolder if not already in dstfolder. dstfolder might assign a new UID (e.g. if uploading to IMAP). Update statusfolder. Pass2: Remove locally deleted messages Get all UIDS in statusfolder but not self. These are messages that were deleted in 'self'. Delete those from dstfolder and statusfolder. After this pass, the message lists should be identical wrt the uids present (except for potential negative uids that couldn't be placed anywhere). Pass3: Synchronize flag changes Compare flag mismatches in self with those in statusfolder. If msg has a valid UID and exists on dstfolder (has not e.g. been deleted there), sync the flag change to both dstfolder and statusfolder. Pass4: Synchronize label changes (Gmail only) Compares label mismatches in self with those in statusfolder. If msg has a valid UID and exists on dstfolder, syncs the labels to both dstfolder and statusfolder. :param dstfolder: Folderinstance to sync the msgs to. :param statusfolder: LocalStatus instance to sync against. """ for (passdesc, action) in self.syncmessagesto_passes: # bail out on CTRL-C or SIGTERM if offlineimap.accounts.Account.abort_NOW_signal.is_set(): break try: action(dstfolder, statusfolder) except (KeyboardInterrupt): raise except OfflineImapError as e: if e.severity > OfflineImapError.ERROR.FOLDER: raise self.ui.error(e, exc_info()[2]) except Exception as e: self.ui.error(e, exc_info()[2], "Syncing folder %s [acc: %s]" %\ (self, self.accountname)) raise # raise unknown Exceptions so we can fix them def __eq__(self, other): """Comparisons work either on string comparing folder names or on the same instance MailDirFolder('foo') == 'foo' --> True a = MailDirFolder('foo'); a == b --> True MailDirFolder('foo') == 'moo' --> False MailDirFolder('foo') == IMAPFolder('foo') --> False MailDirFolder('foo') == MaildirFolder('foo') --> False """ if isinstance(other, basestring): return other == self.name return id(self) == id(other) def __ne__(self, other): return not self.__eq__(other)