Source code for offlineimap.accounts

# Copyright (C) 2003-2016 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

from subprocess import Popen, PIPE
from threading import Event, Lock
import os
import time
from sys import exc_info
import traceback
import six

from offlineimap import mbnames, CustomConfig, OfflineImapError
from offlineimap import globals
from offlineimap.repository import Repository
from offlineimap.ui import getglobalui
from offlineimap.threadutil import InstanceLimitedThread

FOLDER_NAMESPACE = 'LIMITED_FOLDER_'
# Key: account name, Value: Dict of Key: remotefolder name, Value: lock.
SYNC_MUTEXES = {}
SYNC_MUTEXES_LOCK = Lock()

try:
    import fcntl
except:
    pass # Ok if this fails, we can do without.

# FIXME: spaghetti code alert!
def getaccountlist(customconfig):
    # Account names in a list.
    return [name.lstrip() for name in customconfig.getsectionlist('Account')]


[docs]class Account(CustomConfig.ConfigHelperMixin): """Represents an account (ie. 2 repositories) to sync. Most of the time you will actually want to use the derived :class:`accounts.SyncableAccount` which contains all functions used for syncing an account.""" # Signal gets set when we should stop looping. abort_soon_signal = Event() # Signal gets set on CTRL-C/SIGTERM. abort_NOW_signal = Event() def __init__(self, config, name): """ :param config: Representing the offlineimap configuration file. :type config: :class:`offlineimap.CustomConfig.CustomConfigParser` :param name: A (str) string denoting the name of the Account as configured. """ self.config = config self.name = name self.metadatadir = config.getmetadatadir() self.localeval = config.getlocaleval() # Current :mod:`offlineimap.ui`, can be used for logging: self.ui = getglobalui() self.refreshperiod = self.getconffloat('autorefresh', 0.0) self.dryrun = self.config.getboolean('general', 'dry-run') self.quicknum = 0 if self.refreshperiod < 0: self.ui.warn("autorefresh for %s is negative, fixing it to 0."% name) self.refreshperiod = 0.0 if self.refreshperiod == 0.0: self.refreshperiod = None self.remoterepos = None self.localrepos = None self.statusrepos = None def getlocaleval(self): return self.localeval # Interface from CustomConfig.ConfigHelperMixin def getconfig(self): return self.config def getname(self): return self.name def __str__(self): return self.name def getaccountmeta(self): return os.path.join(self.metadatadir, 'Account-' + self.name) # Interface from CustomConfig.ConfigHelperMixin def getsection(self): return 'Account ' + self.getname() @classmethod def set_abort_event(cls, config, signum): """Set skip sleep/abort event for all accounts. If we want to skip a current (or the next) sleep, or if we want to abort an autorefresh loop, the main thread can use set_abort_event() to send the corresponding signal. Signum = 1 implies that we want all accounts to abort or skip the current or next sleep phase. Signum = 2 will end the autorefresh loop, ie all accounts will return after they finished a sync. signum=3 means, abort NOW, e.g. on SIGINT or SIGTERM. This is a class method, it will send the signal to all accounts. """ if signum == 1: # resync signal, set config option for all accounts for acctsection in getaccountlist(config): config.set('Account ' + acctsection, "skipsleep", '1') elif signum == 2: # don't autorefresh anymore cls.abort_soon_signal.set() elif signum == 3: # abort ASAP cls.abort_NOW_signal.set() def get_abort_event(self): """Checks if an abort signal had been sent. If the 'skipsleep' config option for this account had been set, with `set_abort_event(config, 1)` it will get cleared in this function. Ie, we will only skip one sleep and not all. :returns: True, if the main thread had called :meth:`set_abort_event` earlier, otherwise 'False'. """ skipsleep = self.getconfboolean("skipsleep", 0) if skipsleep: self.config.set(self.getsection(), "skipsleep", '0') return skipsleep or Account.abort_soon_signal.is_set() or \ Account.abort_NOW_signal.is_set() def _sleeper(self): """Sleep if the account is set to autorefresh. :returns: 0:timeout expired, 1: canceled the timer, 2:request to abort the program, 100: if configured to not sleep at all. """ if not self.refreshperiod: return 100 kaobjs = [] if hasattr(self, 'localrepos'): kaobjs.append(self.localrepos) if hasattr(self, 'remoterepos'): kaobjs.append(self.remoterepos) for item in kaobjs: item.startkeepalive() refreshperiod = int(self.refreshperiod * 60) sleepresult = self.ui.sleep(refreshperiod, self) # Cancel keepalive for item in kaobjs: item.stopkeepalive() if sleepresult: if Account.abort_soon_signal.is_set() or \ Account.abort_NOW_signal.is_set(): return 2 self.quicknum = 0 return 1 return 0 def serverdiagnostics(self): """Output diagnostics for all involved repositories.""" remote_repo = Repository(self, 'remote') local_repo = Repository(self, 'local') #status_repo = Repository(self, 'status') self.ui.serverdiagnostics(remote_repo, 'Remote') self.ui.serverdiagnostics(local_repo, 'Local') #self.ui.serverdiagnostics(statusrepos, 'Status') def deletefolder(self, foldername): remote_repo = Repository(self, 'remote') try: if self.dryrun: self.ui.info("would try to remove '%s' on remote of '%s' " "account"% (foldername, self)) else: remote_repo.deletefolder(foldername) self.ui.info("Folder '%s' deleted."% foldername) return 0 except Exception as e: self.ui.error(e) return 1
[docs]class SyncableAccount(Account): """A syncable email account connecting 2 repositories. Derives from :class:`accounts.Account` but contains the additional functions :meth:`syncrunner`, :meth:`sync`, :meth:`syncfolders`, used for syncing. In multi-threaded mode, one instance of this object is run per "account" thread.""" def __init__(self, *args, **kwargs): Account.__init__(self, *args, **kwargs) self._lockfd = None self._lockfilepath = os.path.join( self.config.getmetadatadir(), "%s.lock"% self) def __lock(self): """Lock the account, throwing an exception if it is locked already.""" self._lockfd = open(self._lockfilepath, 'w') try: fcntl.lockf(self._lockfd, fcntl.LOCK_EX|fcntl.LOCK_NB) except NameError: #fcntl not available (Windows), disable file locking... :( pass except IOError: self._lockfd.close() six.reraise(OfflineImapError, OfflineImapError( "Could not lock account %s. Is another " "instance using this account?"% self, OfflineImapError.ERROR.REPO), exc_info()[2]) def _unlock(self): """Unlock the account, deleting the lock file""" #If we own the lock file, delete it if self._lockfd and not self._lockfd.closed: self._lockfd.close() try: os.unlink(self._lockfilepath) except OSError: pass # Failed to delete for some reason.
[docs] def syncrunner(self): """The target for both single and multi-threaded modes.""" self.ui.registerthread(self) try: accountmetadata = self.getaccountmeta() if not os.path.exists(accountmetadata): os.mkdir(accountmetadata, 0o700) self.remoterepos = Repository(self, 'remote') self.localrepos = Repository(self, 'local') self.statusrepos = Repository(self, 'status') except OfflineImapError as e: self.ui.error(e, exc_info()[2]) if e.severity >= OfflineImapError.ERROR.CRITICAL: raise return # Loop account sync if needed (bail out after 3 failures). looping = 3 while looping: self.ui.acct(self) try: self.__lock() self.__sync() except (KeyboardInterrupt, SystemExit): raise except OfflineImapError as e: # Stop looping and bubble up Exception if needed. if e.severity >= OfflineImapError.ERROR.REPO: if looping: looping -= 1 if e.severity >= OfflineImapError.ERROR.CRITICAL: raise self.ui.error(e, exc_info()[2]) except Exception as e: self.ui.error(e, exc_info()[2], msg= "While attempting to sync account '%s'"% self) else: # After success sync, reset the looping counter to 3. if self.refreshperiod: looping = 3 finally: self.ui.acctdone(self) self._unlock() if looping and self._sleeper() >= 2: looping = 0
[docs] def get_local_folder(self, remotefolder): """Return the corresponding local folder for a given remotefolder.""" return self.localrepos.getfolder( remotefolder.getvisiblename(). replace(self.remoterepos.getsep(), self.localrepos.getsep()))
def __sync(self): """Synchronize the account once, then return. Assumes that `self.remoterepos`, `self.localrepos`, and `self.statusrepos` has already been populated, so it should only be called from the :meth:`syncrunner` function.""" folderthreads = [] hook = self.getconf('presynchook', '') self.callhook(hook) quickconfig = self.getconfint('quick', 0) if quickconfig < 0: quick = True elif quickconfig > 0: if self.quicknum == 0 or self.quicknum > quickconfig: self.quicknum = 1 quick = False else: self.quicknum = self.quicknum + 1 quick = True else: quick = False try: remoterepos = self.remoterepos localrepos = self.localrepos statusrepos = self.statusrepos # Init repos with list of folders, so we have them (and the # folder delimiter etc). remoterepos.getfolders() localrepos.getfolders() remoterepos.sync_folder_structure(localrepos, statusrepos) # Replicate the folderstructure between REMOTE to LOCAL. if not localrepos.getconfboolean('readonly', False): self.ui.syncfolders(remoterepos, localrepos) # Iterate through all folders on the remote repo and sync. for remotefolder in remoterepos.getfolders(): # Check for CTRL-C or SIGTERM. if Account.abort_NOW_signal.is_set(): break if not remotefolder.sync_this: self.ui.debug('', "Not syncing filtered folder '%s'" "[%s]"% (remotefolder, remoterepos)) continue # Ignore filtered folder. # The remote folder names must not have the local sep char in # their names since this would cause troubles while converting # the name back (from local to remote). sep = localrepos.getsep() if (sep != os.path.sep and sep != remoterepos.getsep() and sep in remotefolder.getname()): self.ui.warn('', "Ignoring folder '%s' due to unsupported " "'%s' character serving as local separator."% (remotefolder.getname(), localrepos.getsep())) continue # Ignore unsupported folder name. localfolder = self.get_local_folder(remotefolder) if not localfolder.sync_this: self.ui.debug('', "Not syncing filtered folder '%s'" "[%s]"% (localfolder, localfolder.repository)) continue # Ignore filtered folder. if not globals.options.singlethreading: thread = InstanceLimitedThread( limitNamespace="%s%s"% ( FOLDER_NAMESPACE, self.remoterepos.getname()), target=syncfolder, name="Folder %s [acc: %s]"% ( remotefolder.getexplainedname(), self), args=(self, remotefolder, quick) ) thread.start() folderthreads.append(thread) else: syncfolder(self, remotefolder, quick) # Wait for all threads to finish. for thr in folderthreads: thr.join() mbnames.writeIntermediateFile(self.name) # Write out mailbox names. localrepos.forgetfolders() remoterepos.forgetfolders() except: # Error while syncing. Drop all connections that we have, they # might be bogus by now (e.g. after suspend). localrepos.dropconnections() remoterepos.dropconnections() raise else: # Sync went fine. Hold or drop depending on config. localrepos.holdordropconnections() remoterepos.holdordropconnections() hook = self.getconf('postsynchook', '') self.callhook(hook) def callhook(self, cmd): # Check for CTRL-C or SIGTERM and run postsynchook. if Account.abort_NOW_signal.is_set(): return if not cmd: return try: self.ui.callhook("Calling hook: " + cmd) if self.dryrun: return p = Popen(cmd, shell=True, stdin=PIPE, stdout=PIPE, stderr=PIPE, close_fds=True) r = p.communicate() self.ui.callhook("Hook stdout: %s\nHook stderr:%s\n"% r) self.ui.callhook("Hook return code: %d"% p.returncode) except (KeyboardInterrupt, SystemExit): raise except Exception as e: self.ui.error(e, exc_info()[2], msg="Calling hook")
#XXX: This function should likely be refactored. This should not be passed the # account instance. def syncfolder(account, remotefolder, quick): """Synchronizes given remote folder for the specified account. Filtered folders on the remote side will not invoke this function. When called in concurrently for the same localfolder, syncs are serialized.""" def acquire_mutex(): account_name = account.getname() localfolder_name = localfolder.getfullname() with SYNC_MUTEXES_LOCK: if SYNC_MUTEXES.get(account_name) is None: SYNC_MUTEXES[account_name] = {} # The localfolder full name is good to uniquely identify the sync # transaction. if SYNC_MUTEXES[account_name].get(localfolder_name) is None: #XXX: This lock could be an external file lock so we can remove # the lock at the account level. SYNC_MUTEXES[account_name][localfolder_name] = Lock() # Acquire the lock. SYNC_MUTEXES[account_name][localfolder_name].acquire() def release_mutex(): SYNC_MUTEXES[account.getname()][localfolder.getfullname()].release() def check_uid_validity(): # If either the local or the status folder has messages and # there is a UID validity problem, warn and abort. If there are # no messages, UW IMAPd loses UIDVALIDITY. But we don't really # need it if both local folders are empty. So, in that case, # just save it off. if localfolder.getmessagecount() > 0 or statusfolder.getmessagecount() > 0: if not localfolder.check_uidvalidity(): ui.validityproblem(localfolder) localfolder.repository.restore_atime() return if not remotefolder.check_uidvalidity(): ui.validityproblem(remotefolder) localrepos.restore_atime() return else: # Both folders empty, just save new UIDVALIDITY. localfolder.save_uidvalidity() remotefolder.save_uidvalidity() def cachemessagelists_upto_date(date): """Returns messages with uid > min(uids of messages newer than date).""" # Warning: this makes sense only if the cached list is empty. localfolder.cachemessagelist(min_date=date) check_uid_validity() # Local messagelist had date restriction applied already. Restrict # sync to messages with UIDs >= min_uid from this list. # # Local messagelist might contain new messages (with uid's < 0). positive_uids = [uid for uid in localfolder.getmessageuidlist() if uid > 0] if len(positive_uids) > 0: remotefolder.cachemessagelist(min_uid=min(positive_uids)) else: # No messages with UID > 0 in range in localfolder. # date restriction was applied with respect to local dates but # remote folder timezone might be different from local, so be # safe and make sure the range isn't bigger than in local. remotefolder.cachemessagelist( min_date=time.gmtime(time.mktime(date) + 24*60*60)) def cachemessagelists_startdate(new, partial, date): """Retrieve messagelists when startdate has been set for the folder 'partial'. Idea: suppose you want to clone the messages after date in one account (partial) to a new one (new). If new is empty, then copy messages in partial newer than date to new, and keep track of the min uid. On subsequent syncs, sync all the messages in new against those after that min uid in partial. This is a partial replacement for maxage in the IMAP-IMAP sync case, where maxage doesn't work: the UIDs of the messages in localfolder might not be in the same order as those of corresponding messages in remotefolder, so if L in local corresponds to R in remote, the ranges [L, ...] and [R, ...] might not correspond. But, if we're cloning a folder into a new one, [min_uid, ...] does correspond to [1, ...]. This is just for IMAP-IMAP. For Maildir-IMAP, use maxage instead.""" new.cachemessagelist() min_uid = partial.retrieve_min_uid() if min_uid == None: # min_uid file didn't exist if len(new.getmessageuidlist()) > 0: raise OfflineImapError("To use startdate on Repository %s, " "Repository %s must be empty"% (partial.repository.name, new.repository.name), OfflineImapError.ERROR.MESSAGE) else: partial.cachemessagelist(min_date=date) # messagelist.keys() instead of getuidmessagelist() because in # the UID mapped case we want the actual local UIDs, not their # remote counterparts. positive_uids = [uid for uid in list(partial.messagelist.keys()) if uid > 0] if len(positive_uids) > 0: min_uid = min(positive_uids) else: min_uid = 1 partial.save_min_uid(min_uid) else: partial.cachemessagelist(min_uid=min_uid) remoterepos = account.remoterepos localrepos = account.localrepos statusrepos = account.statusrepos ui = getglobalui() ui.registerthread(account) try: # Load local folder. localfolder = account.get_local_folder(remotefolder) # Acquire the mutex to start syncing. acquire_mutex() # Add the folder to the mbnames mailboxes. mbnames.add(account.name, localrepos.getlocalroot(), localfolder.getname()) # Load status folder. statusfolder = statusrepos.getfolder(remotefolder.getvisiblename(). replace(remoterepos.getsep(), statusrepos.getsep())) statusfolder.openfiles() statusfolder.cachemessagelist() # Load local folder. ui.syncingfolder(remoterepos, remotefolder, localrepos, localfolder) # Retrieve messagelists, taking into account age-restriction # options. maxage = localfolder.getmaxage() localstart = localfolder.getstartdate() remotestart = remotefolder.getstartdate() if (maxage != None) + (localstart != None) + (remotestart != None) > 1: six.reraise(OfflineImapError, OfflineImapError("You can set at most one of the " "following: maxage, startdate (for the local " "folder), startdate (for the remote folder)", OfflineImapError.ERROR.REPO), exc_info()[2]) if (maxage != None or localstart or remotestart) and quick: # IMAP quickchanged isn't compatible with options that # involve restricting the messagelist, since the "quick" # check can only retrieve a full list of UIDs in the folder. ui.warn("Quick syncs (-q) not supported in conjunction " "with maxage or startdate; ignoring -q.") if maxage != None: cachemessagelists_upto_date(maxage) check_uid_validity() elif localstart != None: cachemessagelists_startdate(remotefolder, localfolder, localstart) check_uid_validity() elif remotestart != None: cachemessagelists_startdate(localfolder, remotefolder, remotestart) check_uid_validity() else: localfolder.cachemessagelist() if quick: if (not localfolder.quickchanged(statusfolder) and not remotefolder.quickchanged(statusfolder)): ui.skippingfolder(remotefolder) localrepos.restore_atime() return check_uid_validity() remotefolder.cachemessagelist() # Synchronize remote changes. if not localrepos.getconfboolean('readonly', False): ui.syncingmessages(remoterepos, remotefolder, localrepos, localfolder) remotefolder.syncmessagesto(localfolder, statusfolder) else: ui.debug('', "Not syncing to read-only repository '%s'"% localrepos.getname()) # Synchronize local changes. if not remoterepos.getconfboolean('readonly', False): ui.syncingmessages(localrepos, localfolder, remoterepos, remotefolder) localfolder.syncmessagesto(remotefolder, statusfolder) else: ui.debug('', "Not syncing to read-only repository '%s'"% remoterepos.getname()) statusfolder.save() localrepos.restore_atime() except (KeyboardInterrupt, SystemExit): raise except OfflineImapError as e: # Bubble up severe Errors, skip folder otherwise. if e.severity > OfflineImapError.ERROR.FOLDER: raise else: ui.error(e, exc_info()[2], msg="Aborting sync, folder '%s' " "[acc: '%s']"% (localfolder, account)) except Exception as e: ui.error(e, msg="ERROR in syncfolder for %s folder %s: %s"% (account, remotefolder.getvisiblename(), traceback.format_exc())) finally: for folder in ["statusfolder", "localfolder", "remotefolder"]: if folder in locals(): locals()[folder].dropmessagelistcache() statusfolder.closefiles() # Release the mutex of this sync transaction. release_mutex()