docker-offlineimap/offlineimap/repository/IMAP.py

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"""
IMAP repository support
Copyright (C) 2002-2019 John Goerzen & contributors
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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 os
import netrc
import errno
from sys import exc_info
from threading import Event
from offlineimap import folder, imaputil, imapserver, OfflineImapError
from offlineimap.repository.Base import BaseRepository
from offlineimap.threadutil import ExitNotifyThread
from offlineimap.utils.distro_utils import get_os_sslcertfile, \
get_os_sslcertfile_searchpath
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class IMAPRepository(BaseRepository):
"""
IMAP Repository Class, children of BaseRepository
"""
def __init__(self, reposname, account):
self.idlefolders = None
BaseRepository.__init__(self, reposname, account)
# self.ui is being set by the BaseRepository
self._host = None
# Must be set before calling imapserver.IMAPServer(self)
self.oauth2_request_url = None
self.imapserver = imapserver.IMAPServer(self)
self.folders = None
self.copy_ignore_eval = None
# Keep alive.
self.kaevent = None
self.kathread = None
# Only set the newmail_hook in an IMAP repository.
if self.config.has_option(self.getsection(), 'newmail_hook'):
self.newmail_hook = self.localeval.eval(
self.getconf('newmail_hook'))
if self.getconf('sep', None):
self.ui.info("The 'sep' setting is being ignored for IMAP "
"repository '%s' (it's autodetected)" % self)
def startkeepalive(self):
keepalivetime = self.getkeepalive()
if not keepalivetime:
return
self.kaevent = Event()
self.kathread = ExitNotifyThread(target=self.imapserver.keepalive,
name="Keep alive " + self.getname(),
args=(keepalivetime, self.kaevent))
self.kathread.setDaemon(True)
self.kathread.start()
def stopkeepalive(self):
if self.kaevent is None:
return # Keepalive is not active.
self.kaevent.set()
self.kathread = None
self.kaevent = None
def holdordropconnections(self):
if not self.getholdconnectionopen():
self.dropconnections()
def dropconnections(self):
self.imapserver.close()
def get_copy_ignore_UIDs(self, foldername):
"""Return a list of UIDs to not copy for this foldername."""
if self.copy_ignore_eval is None:
if self.config.has_option(self.getsection(),
'copy_ignore_eval'):
self.copy_ignore_eval = self.localeval.eval(
self.getconf('copy_ignore_eval'))
else:
self.copy_ignore_eval = lambda x: None
return self.copy_ignore_eval(foldername)
def getholdconnectionopen(self):
"""
Value of holdconnectionopen or False if it is not set
Returns: Value of holdconnectionopen or False if it is not set
"""
if self.getidlefolders():
return True
return self.getconfboolean("holdconnectionopen", False)
def getkeepalive(self):
"""
This function returns the keepalive value. If it is not set, then
check if the getidlefolders is set. If getidlefolders is set, then
returns 29 * 60
Returns: keepalive value
"""
num = self.getconfint("keepalive", 0)
if num == 0 and self.getidlefolders():
return 29 * 60
return num
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def getsep(self):
"""Return the folder separator for the IMAP repository
This requires that self.imapserver has been initialized with an
acquireconnection() or it will still be `None`"""
assert self.imapserver.delim is not None, \
"'%s' repository called getsep() before the folder separator was " \
"queried from the server" % self
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return self.imapserver.delim
def gethost(self):
"""Return the configured hostname to connect to
:returns: hostname as string or throws Exception"""
if self._host: # Use cached value if possible.
return self._host
# 1) Check for remotehosteval setting.
if self.config.has_option(self.getsection(), 'remotehosteval'):
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host = self.getconf('remotehosteval')
try:
host = self.localeval.eval(host)
except Exception as exc:
raise OfflineImapError(
"remotehosteval option for repository "
"'%s' failed:\n%s" % (self, exc),
OfflineImapError.ERROR.REPO,
exc_info()[2]) from exc
if host:
self._host = host
return self._host
# 2) Check for plain remotehost setting.
host = self.getconf('remotehost', None)
if host is not None:
self._host = host
return self._host
# No success.
raise OfflineImapError("No remote host for repository "
"'%s' specified." % self,
OfflineImapError.ERROR.REPO)
def get_remote_identity(self):
"""Remote identity is used for certain SASL mechanisms
(currently -- PLAIN) to inform server about the ID
we want to authorize as instead of our login name."""
identity = self.getconf('remote_identity', default=None)
if identity is not None:
identity = identity.encode('UTF-8')
return identity
def get_auth_mechanisms(self):
"""
Get the AUTH mechanisms. We have (ranged from the strongest to weakest)
these methods: "GSSAPI", "XOAUTH2", "CRAM-MD5", "PLAIN", "LOGIN"
Returns: The supported AUTH Methods
"""
supported = ["GSSAPI", "XOAUTH2", "CRAM-MD5", "PLAIN", "LOGIN"]
# Mechanisms are ranged from the strongest to the
# weakest ones.
# TODO: we need DIGEST-MD5, it must come before CRAM-MD5
# due to the chosen-plaintext resistance.
default = ["GSSAPI", "XOAUTH2", "CRAM-MD5", "PLAIN", "LOGIN"]
mechs = self.getconflist('auth_mechanisms', r',\s*',
default)
for mech in mechs:
if mech not in supported:
raise OfflineImapError("Repository %s: " % self +
"unknown authentication mechanism '%s'"
% mech, OfflineImapError.ERROR.REPO)
self.ui.debug('imap', "Using authentication mechanisms %s" % mechs)
return mechs
def getuser(self):
"""
Returns the remoteusereval or remoteuser or netrc user value.
Returns: Returns the remoteusereval or remoteuser or netrc user value.
"""
localeval = self.localeval
if self.config.has_option(self.getsection(), 'remoteusereval'):
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user = self.getconf('remoteusereval')
if user is not None:
return localeval.eval(user).encode('UTF-8')
if self.config.has_option(self.getsection(), 'remoteuser'):
# Assume the configuration file to be UTF-8 encoded so we must not
# encode this string again.
user = self.getconf('remoteuser')
if user is not None:
return user
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try:
netrcentry = netrc.netrc().authenticators(self.gethost())
except IOError as inst:
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if inst.errno != errno.ENOENT:
raise
else:
if netrcentry:
return netrcentry[0]
try:
netrcentry = netrc.netrc('/etc/netrc')\
.authenticators(self.gethost())
except IOError as inst:
if inst.errno not in (errno.ENOENT, errno.EACCES):
raise
else:
if netrcentry:
return netrcentry[0]
def getport(self):
"""
Returns remoteporteval value or None if not found.
Returns: Returns remoteporteval int value or None if not found.
"""
port = None
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if self.config.has_option(self.getsection(), 'remoteporteval'):
port = self.getconf('remoteporteval')
if port is not None:
return self.localeval.eval(port)
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return self.getconfint('remoteport', None)
def getipv6(self):
"""
Returns if IPv6 is set. If not set, then return None
Returns: Boolean flag if IPv6 is set.
"""
return self.getconfboolean('ipv6', None)
def getssl(self):
"""
Get the boolean SSL value. Default is True, used if not found.
Returns: Get the boolean SSL value. Default is True
"""
return self.getconfboolean('ssl', True)
def getsslclientcert(self):
"""
Return the SSL client cert (sslclientcert) or None if not found
Returns: SSL client key (sslclientcert) or None if not found
"""
xforms = [os.path.expanduser, os.path.expandvars, os.path.abspath]
return self.getconf_xform('sslclientcert', xforms, None)
def getsslclientkey(self):
"""
Return the SSL client key (sslclientkey) or None if not found
Returns: SSL client key (sslclientkey) or None if not found
"""
xforms = [os.path.expanduser, os.path.expandvars, os.path.abspath]
return self.getconf_xform('sslclientkey', xforms, None)
def getsslcacertfile(self):
"""Determines CA bundle.
Returns path to the CA bundle. It is explicitely specified or
requested via "OS-DEFAULT" value (and we will search known
locations for the current OS and distribution). If it is not
specified, we will search it in the known locations.
If search route, via "OS-DEFAULT" or because is not specified,
yields nothing, we will throw an exception to make our callers
distinguish between not specified value and non-existent
default CA bundle.
It is also an error to specify non-existent file via configuration:
it will error out later, but, perhaps, with less verbose explanation,
so we will also throw an exception. It is consistent with
the above behaviour, so any explicitely-requested configuration
that doesn't result in an existing file will give an exception.
"""
xforms = [os.path.expanduser, os.path.expandvars, os.path.abspath]
cacertfile = self.getconf_xform('sslcacertfile', xforms, None)
# Can't use above cacertfile because of abspath.
conf_sslacertfile = self.getconf('sslcacertfile', None)
if conf_sslacertfile == "OS-DEFAULT" or \
conf_sslacertfile is None or \
conf_sslacertfile == '':
cacertfile = get_os_sslcertfile()
if cacertfile is None:
searchpath = get_os_sslcertfile_searchpath()
if searchpath:
reason = "Default CA bundle was requested, " \
"but no existing locations available. " \
"Tried %s." % (", ".join(searchpath))
else:
reason = "Default CA bundle was requested, " \
"but OfflineIMAP doesn't know any for your " \
"current operating system."
raise OfflineImapError(reason, OfflineImapError.ERROR.REPO)
if cacertfile is None:
return None
if not os.path.isfile(cacertfile):
reason = "CA certfile for repository '%s' couldn't be found. " \
"No such file: '%s'" % (self.name, cacertfile)
raise OfflineImapError(reason, OfflineImapError.ERROR.REPO)
return cacertfile
def gettlslevel(self):
"""
Returns the TLS level (tls_level). If not set, returns 'tls_compat'
Returns: TLS level (tls_level). If not set, returns 'tls_compat'
"""
return self.getconf('tls_level', 'tls_compat')
def getsslversion(self):
"""
Returns the SSL version. If not set, returns None.
Returns: SSL version. If not set, returns None.
"""
return self.getconf('ssl_version', None)
def getstarttls(self):
"""
Get the value of starttls. If not set, returns True
Returns: Value of starttls. If not set, returns True
"""
return self.getconfboolean('starttls', True)
def get_ssl_fingerprint(self):
"""Return array of possible certificate fingerprints.
Configuration item cert_fingerprint can contain multiple
comma-separated fingerprints in hex form."""
value = self.getconf('cert_fingerprint', "")
return [f.strip().lower().replace(":", "")
for f in value.split(',') if f]
def setoauth2_request_url(self, url):
"""
Set the OAUTH2 URL request.
Args:
url: OAUTH2 URL request
Returns: None
"""
self.oauth2_request_url = url
def getoauth2_request_url(self):
"""
Returns the OAUTH2 URL request from configuration (oauth2_request_url).
If it is not found, then returns None
Returns: OAUTH2 URL request (oauth2_request_url)
"""
if self.oauth2_request_url is not None: # Use cached value if possible.
return self.oauth2_request_url
self.setoauth2_request_url(self.getconf('oauth2_request_url', None))
return self.oauth2_request_url
def getoauth2_refresh_token(self):
"""
Get the OAUTH2 refresh token from the configuration
(oauth2_refresh_token)
If the access token is not found, then returns None.
Returns: OAUTH2 refresh token (oauth2_refresh_token)
"""
refresh_token = self.getconf('oauth2_refresh_token', None)
if refresh_token is None:
refresh_token = self.localeval.eval(
self.getconf('oauth2_refresh_token_eval', "None")
)
if refresh_token is not None:
refresh_token = refresh_token.strip("\n")
return refresh_token
def getoauth2_access_token(self):
"""
Get the OAUTH2 access token from the configuration (oauth2_access_token)
If the access token is not found, then returns None.
Returns: OAUTH2 access token (oauth2_access_token)
"""
access_token = self.getconf('oauth2_access_token', None)
if access_token is None:
access_token = self.localeval.eval(
self.getconf('oauth2_access_token_eval', "None")
)
if access_token is not None:
access_token = access_token.strip("\n")
return access_token
def getoauth2_client_id(self):
"""
Get the OAUTH2 client id (oauth2_client_id) from the configuration.
If not found, returns None
Returns: OAUTH2 client id (oauth2_client_id)
"""
client_id = self.getconf('oauth2_client_id', None)
if client_id is None:
client_id = self.localeval.eval(
self.getconf('oauth2_client_id_eval', "None")
)
if client_id is not None:
client_id = client_id.strip("\n")
return client_id
def getoauth2_client_secret(self):
"""
Get the OAUTH2 client secret (oauth2_client_secret) from the
configuration. If it is not found, then returns None.
Returns: OAUTH2 client secret
"""
client_secret = self.getconf('oauth2_client_secret', None)
if client_secret is None:
client_secret = self.localeval.eval(
self.getconf('oauth2_client_secret_eval', "None")
)
if client_secret is not None:
client_secret = client_secret.strip("\n")
return client_secret
def getpreauthtunnel(self):
"""
Get the value of preauthtunnel. If not found, then returns None.
Returns: Returns preauthtunnel value. If not found, returns None.
"""
return self.getconf('preauthtunnel', None)
def gettransporttunnel(self):
"""
Get the value of transporttunnel. If not found, then returns None.
Returns: Returns transporttunnel value. If not found, returns None.
"""
return self.getconf('transporttunnel', None)
def getreference(self):
"""
Get the reference value in the configuration. If the value is not found
then returns a double quote ("") as string.
Returns: The reference variable. If not set, then returns '""'
"""
return self.getconf('reference', '""')
def getdecodefoldernames(self):
"""
Get the boolean value of decodefoldernames configuration variable,
if the value is not found, returns False.
Returns: Boolean value of decodefoldernames, else False
"""
return self.getconfboolean('decodefoldernames', False)
def getidlefolders(self):
"""
Get the list of idlefolders from configuration. If the value is not
found, returns an empty list.
Returns: A list of idle folders
"""
if self.idlefolders is None:
self.idlefolders = self.localeval.eval(
self.getconf('idlefolders', '[]')
)
return self.idlefolders
def getmaxconnections(self):
"""
Get the maxconnections configuration value from configuration.
If the value is not set, returns 1 connection
Returns: Integer value of maxconnections configuration variable, else 1
"""
num1 = len(self.getidlefolders())
num2 = self.getconfint('maxconnections', 1)
return max(num1, num2)
def getexpunge(self):
"""
Get the expunge configuration value from configuration.
If the value is not set in the configuration, then returns True
Returns: Boolean value of expunge configuration variable
"""
return self.getconfboolean('expunge', True)
def getpassword(self):
"""Return the IMAP password for this repository.
It tries to get passwords in the following order:
1. evaluate Repository 'remotepasseval'
2. read password from Repository 'remotepass'
3. read password from file specified in Repository 'remotepassfile'
4. read password from ~/.netrc
5. read password from /etc/netrc
On success we return the password.
If all strategies fail we return None."""
# 1. Evaluate Repository 'remotepasseval'.
passwd = self.getconf('remotepasseval', None)
if passwd is not None:
l_pass = self.localeval.eval(passwd)
# We need a str password
if isinstance(l_pass, bytes):
return l_pass.decode(encoding='utf-8')
elif isinstance(l_pass, str):
return l_pass
# If is not bytes or str, we have a problem
raise OfflineImapError("Could not get a right password format for"
" repository %s. Type found: %s. "
"Please, open a bug." %
(self.name, type(l_pass)),
OfflineImapError.ERROR.FOLDER)
# 2. Read password from Repository 'remotepass'.
password = self.getconf('remotepass', None)
if password is not None:
# Assume the configuration file to be UTF-8 encoded so we must not
# encode this string again.
return password
# 3. Read password from file specified in Repository 'remotepassfile'.
passfile = self.getconf('remotepassfile', None)
if passfile is not None:
file_desc = open(os.path.expanduser(passfile), 'r',
encoding='utf-8')
password = file_desc.readline().strip()
file_desc.close()
return password.encode('UTF-8')
# 4. Read password from ~/.netrc.
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try:
netrcentry = netrc.netrc().authenticators(self.gethost())
except IOError as inst:
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if inst.errno != errno.ENOENT:
raise
else:
if netrcentry:
user = self.getuser()
if user is None or user == netrcentry[0]:
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return netrcentry[2]
# 5. Read password from /etc/netrc.
try:
netrcentry = netrc.netrc('/etc/netrc')\
.authenticators(self.gethost())
except IOError as inst:
if inst.errno not in (errno.ENOENT, errno.EACCES):
raise
else:
if netrcentry:
user = self.getuser()
if user is None or user == netrcentry[0]:
return netrcentry[2]
# No strategy yielded a password!
return None
def getfolder(self, foldername, decode=True):
"""Return instance of OfflineIMAP representative folder."""
return self.getfoldertype()(self.imapserver, foldername, self, decode)
def getfoldertype(self):
"""
This function returns the folder type, in this case
folder.IMAP.IMAPFolder
Returns: folder.IMAP.IMAPFolder
"""
return folder.IMAP.IMAPFolder
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def connect(self):
imapobj = self.imapserver.acquireconnection()
self.imapserver.releaseconnection(imapobj)
def forgetfolders(self):
self.folders = None
def getfolders(self):
"""Return a list of instances of OfflineIMAP representative folder."""
if self.folders is not None:
return self.folders
retval = []
imapobj = self.imapserver.acquireconnection()
# check whether to list all folders, or subscribed only
listfunction = imapobj.list
if self.getconfboolean('subscribedonly', False):
listfunction = imapobj.lsub
try:
result, listresult = \
listfunction(directory=self.imapserver.reference, pattern='"*"')
if result != 'OK':
raise OfflineImapError("Could not list the folders for"
" repository %s. Server responded: %s" %
(self.name, str(listresult)),
OfflineImapError.ERROR.FOLDER)
finally:
self.imapserver.releaseconnection(imapobj)
for fldr in listresult:
if fldr is None or (isinstance(fldr, str) and fldr == ''):
# Bug in imaplib: empty strings in results from
# literals. TODO: still relevant?
continue
try:
flags, delim, name = imaputil.imapsplit(fldr)
except ValueError:
self.ui.error(
"could not correctly parse server response; got: %s" % fldr)
raise
flaglist = [x.lower() for x in imaputil.flagsplit(flags)]
if '\\noselect' in flaglist:
continue
retval.append(self.getfoldertype()(self.imapserver, name,
self))
# Add all folderincludes
if len(self.folderincludes):
imapobj = self.imapserver.acquireconnection()
try:
for foldername in self.folderincludes:
try:
imapobj.select(imaputil.utf8_IMAP(foldername),
readonly=True)
except OfflineImapError as exc:
# couldn't select this folderinclude, so ignore folder.
if exc.severity > OfflineImapError.ERROR.FOLDER:
raise
self.ui.error(exc, exc_info()[2],
'Invalid folderinclude:')
continue
retval.append(self.getfoldertype()(
self.imapserver, foldername, self, decode=False))
finally:
self.imapserver.releaseconnection(imapobj)
if self.foldersort is None:
# default sorting by case insensitive transposed name
retval.sort(key=lambda x: str.lower(x.getvisiblename()))
else:
# do foldersort in a python3-compatible way
# http://bytes.com/topic/python/answers/ \
# 844614-python-3-sorting-comparison-function
def cmp2key(mycmp):
"""Converts a cmp= function into a key= function
We need to keep cmp functions for backward compatibility"""
class K:
"""
Class to compare getvisiblename() between two objects.
"""
def __init__(self, obj, *args):
self.obj = obj
def __cmp__(self, other):
return mycmp(self.obj.getvisiblename(),
other.obj.getvisiblename())
foldersort broken with instance comparison This patch solves a problem about the comparison of mails used in foldersort. When foldersort is used, for example with: lambda x,y: -cmp(x,y) The user gets an error: ERROR: While attempting to sync account 'accountname' '<' not supported between instances of 'K' and 'K' Traceback: File "offlineimap3/offlineimap/accounts.py", line 298, in syncrunner self.__sync() File "offlineimap3/offlineimap/accounts.py", line 374, in __sync remoterepos.getfolders() File "offlineimap3/offlineimap/repository/IMAP.py", line 725, in getfolders retval.sort(key=cmp2key(self.foldersort)) The problem is because in Python 3, we must specify all parameters for total_ordering (see https://docs.python.org/3/library/functools.html in the functools.total_ordering block): Given a class defining one or more rich comparison ordering methods, this class decorator supplies the rest. This simplifies the effort involved in specifying all of the possible rich comparison operations: The class must define one of __lt__(), __le__(), __gt__(), or __ge__(). In addition, the class should supply an __eq__() method. Also, see: https://docs.python.org/3.1/library/stdtypes.html#comparisons Instances of a class cannot be ordered with respect to other instances of the same class, or other types of object, unless the class defines enough of the methods __lt__(), __le__(), __gt__(), and __ge__() (in general, __lt__() and __eq__() are sufficient, if you want the conventional meanings of the comparison operators). This patch implements all methods. Closes #33
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def __lt__(self, other):
return self.__cmp__(other) < 0
def __le__(self, other):
return self.__cmp__(other) <= 0
def __gt__(self, other):
return self.__cmp__(other) > 0
def __ge__(self, other):
return self.__cmp__(other) >= 0
def __eq__(self, other):
return self.__cmp__(other) == 0
def __ne__(self, other):
return self.__cmp__(other) != 0
return K
retval.sort(key=cmp2key(self.foldersort))
self.folders = retval
return self.folders
def deletefolder(self, foldername):
"""Delete a folder on the IMAP server."""
if self.account.utf_8_support:
foldername = imaputil.utf8_IMAP(foldername)
imapobj = self.imapserver.acquireconnection()
try:
result = imapobj.delete(foldername)
if result[0] != 'OK':
msg = "Folder '%s'[%s] could not be deleted. "\
"Server responded: %s" % (foldername, self, str(result))
raise OfflineImapError(msg, OfflineImapError.ERROR.FOLDER)
finally:
self.imapserver.releaseconnection(imapobj)
def makefolder(self, foldername):
"""
Create a folder on the IMAP server
This will not update the list cached in :meth:`getfolders`. You
will need to invoke :meth:`forgetfolders` to force new caching
when you are done creating folders yourself.
Args:
foldername: Full path of the folder to be created
Returns: None
"""
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if foldername == '':
return
if self.getreference() != '""':
foldername = self.getreference() + self.getsep() + foldername
if not foldername: # Create top level folder as folder separator.
foldername = self.getsep()
self.makefolder_single(foldername)
return
parts = foldername.split(self.getsep())
folder_paths = [self.getsep().join(parts[:n + 1])
for n in range(len(parts))]
for folder_path in folder_paths:
try:
self.makefolder_single(folder_path)
except OfflineImapError as exc:
if '[ALREADYEXISTS]' not in exc.reason:
raise
def makefolder_single(self, foldername):
"""
Create a IMAP folder.
Args:
foldername: Folder's name to create
Returns: None
"""
self.ui.makefolder(self, foldername)
if self.account.dryrun:
return
imapobj = self.imapserver.acquireconnection()
try:
if self.account.utf_8_support:
foldername = imaputil.utf8_IMAP(foldername)
result = imapobj.create(foldername)
if result[0] != 'OK':
msg = "Folder '%s'[%s] could not be created. "\
"Server responded: %s" % (foldername, self, str(result))
raise OfflineImapError(msg, OfflineImapError.ERROR.FOLDER)
finally:
self.imapserver.releaseconnection(imapobj)
class MappedIMAPRepository(IMAPRepository):
"""
This subclass of IMAPRepository includes only the method
getfoldertype modified that returns folder.UIDMaps.MappedIMAPFolder
instead of folder.IMAP.IMAPFolder
"""
def getfoldertype(self):
return folder.UIDMaps.MappedIMAPFolder