notmuch/bindings/python/notmuch/globals.py
Justus Winter 7ddd849015 py3k: add a specialized version of _str for python3
All strings are unicode strings in python 3 and the basestring and
unicode types are removed hence the need for a specialized version.

Signed-off-by: Justus Winter <4winter@informatik.uni-hamburg.de>
2012-01-16 13:43:11 +01:00

269 lines
8 KiB
Python

"""
This file is part of notmuch.
Notmuch 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 3 of the License, or (at your
option) any later version.
Notmuch 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 notmuch. If not, see <http://www.gnu.org/licenses/>.
Copyright 2010 Sebastian Spaeth <Sebastian@SSpaeth.de>'
"""
import sys
from ctypes import CDLL, c_char_p, c_int, Structure, POINTER
#-----------------------------------------------------------------------------
#package-global instance of the notmuch library
try:
nmlib = CDLL("libnotmuch.so.2")
except:
raise ImportError("Could not find shared 'notmuch' library.")
if sys.version_info[0] == 2:
class Python3StringMixIn(object):
def __str__(self):
return unicode(self).encode('utf-8')
def _str(value):
"""Ensure a nicely utf-8 encoded string to pass to libnotmuch
C++ code expects strings to be well formatted and
unicode strings to have no null bytes."""
if not isinstance(value, basestring):
raise TypeError("Expected str or unicode, got %s" % type(value))
if isinstance(value, unicode):
return value.encode('UTF-8')
return value
else:
class Python3StringMixIn(object):
def __str__(self):
return self.__unicode__()
def _str(value):
"""Ensure a nicely utf-8 encoded string to pass to libnotmuch
C++ code expects strings to be well formatted and
unicode strings to have no null bytes."""
if not isinstance(value, str):
raise TypeError("Expected str, got %s" % type(value))
return value.encode('UTF-8')
class Enum(object):
"""Provides ENUMS as "code=Enum(['a','b','c'])" where code.a=0 etc..."""
def __init__(self, names):
for number, name in enumerate(names):
setattr(self, name, number)
class Status(Enum):
"""Enum with a string representation of a notmuch_status_t value."""
_status2str = nmlib.notmuch_status_to_string
_status2str.restype = c_char_p
_status2str.argtypes = [c_int]
def __init__(self, statuslist):
"""It is initialized with a list of strings that are available as
Status().string1 - Status().stringn attributes.
"""
super(Status, self).__init__(statuslist)
@classmethod
def status2str(self, status):
"""Get a (unicode) string representation of a notmuch_status_t value."""
# define strings for custom error messages
if status == STATUS.NOT_INITIALIZED:
return "Operation on uninitialized object impossible."
return unicode(Status._status2str(status))
STATUS = Status(['SUCCESS',
'OUT_OF_MEMORY',
'READ_ONLY_DATABASE',
'XAPIAN_EXCEPTION',
'FILE_ERROR',
'FILE_NOT_EMAIL',
'DUPLICATE_MESSAGE_ID',
'NULL_POINTER',
'TAG_TOO_LONG',
'UNBALANCED_FREEZE_THAW',
'UNBALANCED_ATOMIC',
'NOT_INITIALIZED'])
"""STATUS is a class, whose attributes provide constants that serve as return
indicators for notmuch functions. Currently the following ones are defined. For
possible return values and specific meaning for each method, see the method
description.
* SUCCESS
* OUT_OF_MEMORY
* READ_ONLY_DATABASE
* XAPIAN_EXCEPTION
* FILE_ERROR
* FILE_NOT_EMAIL
* DUPLICATE_MESSAGE_ID
* NULL_POINTER
* TAG_TOO_LONG
* UNBALANCED_FREEZE_THAW
* UNBALANCED_ATOMIC
* NOT_INITIALIZED
Invoke the class method `notmuch.STATUS.status2str` with a status value as
argument to receive a human readable string"""
STATUS.__name__ = 'STATUS'
class NotmuchError(Exception, Python3StringMixIn):
"""Is initiated with a (notmuch.STATUS[, message=None]). It will not
return an instance of the class NotmuchError, but a derived instance
of a more specific Error Message, e.g. OutOfMemoryError. Each status
but SUCCESS has a corresponding subclassed Exception."""
@classmethod
def get_exc_subclass(cls, status):
"""Returns a fine grained Exception() type,
detailing the error status"""
subclasses = {
STATUS.OUT_OF_MEMORY: OutOfMemoryError,
STATUS.READ_ONLY_DATABASE: ReadOnlyDatabaseError,
STATUS.XAPIAN_EXCEPTION: XapianError,
STATUS.FILE_ERROR: FileError,
STATUS.FILE_NOT_EMAIL: FileNotEmailError,
STATUS.DUPLICATE_MESSAGE_ID: DuplicateMessageIdError,
STATUS.NULL_POINTER: NullPointerError,
STATUS.TAG_TOO_LONG: TagTooLongError,
STATUS.UNBALANCED_FREEZE_THAW: UnbalancedFreezeThawError,
STATUS.UNBALANCED_ATOMIC: UnbalancedAtomicError,
STATUS.NOT_INITIALIZED: NotInitializedError,
}
assert 0 < status <= len(subclasses)
return subclasses[status]
def __new__(cls, *args, **kwargs):
"""Return a correct subclass of NotmuchError if needed
We return a NotmuchError instance if status is None (or 0) and a
subclass that inherits from NotmuchError depending on the
'status' parameter otherwise."""
# get 'status'. Passed in as arg or kwarg?
status = args[0] if len(args) else kwargs.get('status', None)
# no 'status' or cls is subclass already, return 'cls' instance
if not status or cls != NotmuchError:
return super(NotmuchError, cls).__new__(cls)
subclass = cls.get_exc_subclass(status) # which class to use?
return subclass.__new__(subclass, *args, **kwargs)
def __init__(self, status=None, message=None):
self.status = status
self.message = message
def __unicode__(self):
if self.message is not None:
return self.message
elif self.status is not None:
return STATUS.status2str(self.status)
else:
return 'Unknown error'
# List of Subclassed exceptions that correspond to STATUS values and are
# subclasses of NotmuchError.
class OutOfMemoryError(NotmuchError):
status = STATUS.OUT_OF_MEMORY
class ReadOnlyDatabaseError(NotmuchError):
status = STATUS.READ_ONLY_DATABASE
class XapianError(NotmuchError):
status = STATUS.XAPIAN_EXCEPTION
class FileError(NotmuchError):
status = STATUS.FILE_ERROR
class FileNotEmailError(NotmuchError):
status = STATUS.FILE_NOT_EMAIL
class DuplicateMessageIdError(NotmuchError):
status = STATUS.DUPLICATE_MESSAGE_ID
class NullPointerError(NotmuchError):
status = STATUS.NULL_POINTER
class TagTooLongError(NotmuchError):
status = STATUS.TAG_TOO_LONG
class UnbalancedFreezeThawError(NotmuchError):
status = STATUS.UNBALANCED_FREEZE_THAW
class UnbalancedAtomicError(NotmuchError):
status = STATUS.UNBALANCED_ATOMIC
class NotInitializedError(NotmuchError):
"""Derived from NotmuchError, this occurs if the underlying data
structure (e.g. database is not initialized (yet) or an iterator has
been exhausted. You can test for NotmuchError with .status =
STATUS.NOT_INITIALIZED"""
status = STATUS.NOT_INITIALIZED
class NotmuchDatabaseS(Structure):
pass
NotmuchDatabaseP = POINTER(NotmuchDatabaseS)
class NotmuchQueryS(Structure):
pass
NotmuchQueryP = POINTER(NotmuchQueryS)
class NotmuchThreadsS(Structure):
pass
NotmuchThreadsP = POINTER(NotmuchThreadsS)
class NotmuchThreadS(Structure):
pass
NotmuchThreadP = POINTER(NotmuchThreadS)
class NotmuchMessagesS(Structure):
pass
NotmuchMessagesP = POINTER(NotmuchMessagesS)
class NotmuchMessageS(Structure):
pass
NotmuchMessageP = POINTER(NotmuchMessageS)
class NotmuchTagsS(Structure):
pass
NotmuchTagsP = POINTER(NotmuchTagsS)
class NotmuchDirectoryS(Structure):
pass
NotmuchDirectoryP = POINTER(NotmuchDirectoryS)
class NotmuchFilenamesS(Structure):
pass
NotmuchFilenamesP = POINTER(NotmuchFilenamesS)