+
−# copyright 2003-2016 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
+
−# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
+
−#
+
−# This file is part of CubicWeb.
+
−#
+
−# CubicWeb is free software: you can redistribute it and/or modify it under the
+
−# terms of the GNU Lesser General Public License as published by the Free
+
−# Software Foundation, either version 2.1 of the License, or (at your option)
+
−# any later version.
+
−#
+
−# CubicWeb 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 Lesser General Public License for more
+
−# details.
+
−#
+
−# You should have received a copy of the GNU Lesser General Public License along
+
−# with CubicWeb.  If not, see <http://www.gnu.org/licenses/>.
+
−"""CubicWeb is a generic framework to quickly build applications which describes
+
−relations between entitites.
+
−"""
+
−
+
−
+
−import logging
+
−import os
+
−import pickle
+
−import sys
+
−import warnings
+
−import zlib
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−
+
−from logilab.common.logging_ext import set_log_methods
+
−from yams.constraints import BASE_CONVERTERS, BASE_CHECKERS
+
−from yams.schema import role_name as rname
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−
+
−from cubicweb.__pkginfo__ import version as __version__   # noqa
+
−
+
−# make all exceptions accessible from the package
+
−from logilab.common.registry import ObjectNotFound, NoSelectableObject, RegistryNotFound  # noqa
+
−from yams import ValidationError
+
−from cubicweb._exceptions import *  # noqa
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−
+
−from io import BytesIO
+
−
+
−# ignore the pygments UserWarnings
+
−warnings.filterwarnings('ignore', category=UserWarning,
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−                        message='.*was already imported',
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−                        module='.*pygments')
+
−
+
−# pre python 2.7.2 safety
+
−logging.basicConfig()
+
−set_log_methods(sys.modules[__name__], logging.getLogger('cubicweb'))
+
−
+
−# this is necessary for i18n devtools test where chdir is done while __path__ is relative, which
+
−# breaks later imports
+
−__path__[0] = os.path.abspath(__path__[0])  # noqa
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−CW_SOFTWARE_ROOT = __path__[0]  # noqa
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−
+
−
+
−# '_' is available to mark internationalized string but should not be used to
+
−# do the actual translation
+
−_ = str
+
−
+
−
+
−class Binary(BytesIO):
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−    """class to hold binary data. Use BytesIO to prevent use of unicode data"""
+
−    _allowed_types = (bytes, bytearray, memoryview)
+
−
+
−    def __init__(self, buf=b''):
+
−        assert isinstance(buf, self._allowed_types), \
+
−            "Binary objects must use bytes/buffer objects, not %s" % buf.__class__
+
−        # don't call super, BytesIO may be an old-style class (on python < 2.7.4)
+
−        BytesIO.__init__(self, buf)
+
−
+
−    def write(self, data):
+
−        assert isinstance(data, self._allowed_types), \
+
−            "Binary objects must use bytes/buffer objects, not %s" % data.__class__
+
−        # don't call super, BytesIO may be an old-style class (on python < 2.7.4)
+
−        BytesIO.write(self, data)
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−
+
−    def to_file(self, fobj):
+
−        """write a binary to disk
+
−
+
−        the writing is performed in a safe way for files stored on
+
−        Windows SMB shares
+
−        """
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−        pos = self.tell()
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−        self.seek(0)
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−        if sys.platform == 'win32':
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−            while True:
+
−                # the 16kB chunksize comes from the shutil module
+
−                # in stdlib
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−                chunk = self.read(16 * 1024)
+
−                if not chunk:
+
−                    break
+
−                fobj.write(chunk)
+
−        else:
+
−            fobj.write(self.read())
+
−        self.seek(pos)
+
−
+
−    @staticmethod
+
−    def from_file(filename):
+
−        """read a file and returns its contents in a Binary
+
−
+
−        the reading is performed in a safe way for files stored on
+
−        Windows SMB shares
+
−        """
+
−        binary = Binary()
+
−        with open(filename, 'rb') as fobj:
+
−            if sys.platform == 'win32':
+
−                while True:
+
−                    # the 16kB chunksize comes from the shutil module
+
−                    # in stdlib
+
−                    chunk = fobj.read(16 * 1024)
+
−                    if not chunk:
+
−                        break
+
−                    binary.write(chunk)
+
−            else:
+
−                binary.write(fobj.read())
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−        binary.seek(0)
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−        return binary
+
−
+
−    def __eq__(self, other):
+
−        if not isinstance(other, Binary):
+
−            return False
+
−        return self.getvalue() == other.getvalue()
+
−
+
−    # Binary helpers to store/fetch python objects
+
−
+
−    @classmethod
+
−    def zpickle(cls, obj):
+
−        """ return a Binary containing a gzipped pickle of obj """
+
−        retval = cls()
+
−        retval.write(zlib.compress(pickle.dumps(obj, protocol=2)))
+
−        return retval
+
−
+
−    def unzpickle(self):
+
−        """ decompress and loads the stream before returning it """
+
−        return pickle.loads(zlib.decompress(self.getvalue()))
+
−
+
−
+
−def check_password(eschema, value):
+
−    return isinstance(value, (bytes, Binary))
+
−
+
−
+
−BASE_CHECKERS['Password'] = check_password
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−
+
−
+
−def str_or_binary(value):
+
−    if isinstance(value, Binary):
+
−        return value
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−    return bytes(value)
+
−
+
−
+
−BASE_CONVERTERS['Password'] = str_or_binary
+
−
+
−
+
−# use this dictionary to rename entity types while keeping bw compat
+
−ETYPE_NAME_MAP = {}
+
−
+
−# XXX cubic web cube migration map. See if it's worth keeping this mecanism
+
−#     to help in cube renaming
+
−CW_MIGRATION_MAP = {}
+
−
+
−
+
−def neg_role(role):
+
−    if role == 'subject':
+
−        return 'object'
+
−    return 'subject'
+
−
+
−
+
−def role(obj):
+
−    try:
+
−        return obj.role
+
−    except AttributeError:
+
−        return neg_role(obj.target)
+
−
+
−
+
−def target(obj):
+
−    try:
+
−        return obj.target
+
−    except AttributeError:
+
−        return neg_role(obj.role)
+
−
+
−
+
−class CubicWebEventManager(object):
+
−    """simple event / callback manager.
+
−
+
−    Typical usage to register a callback::
+
−
+
−      >>> from cubicweb import CW_EVENT_MANAGER
+
−      >>> CW_EVENT_MANAGER.bind('after-registry-reload', mycallback)
+
−
+
−    Typical usage to emit an event::
+
−
+
−      >>> from cubicweb import CW_EVENT_MANAGER
+
−      >>> CW_EVENT_MANAGER.emit('after-registry-reload')
+
−
+
−    emit() accepts an additional context parameter that will be passed
+
−    to the callback if specified (and only in that case)
+
−    """
+
−    def __init__(self):
+
−        self.callbacks = {}
+
−
+
−    def bind(self, event, callback, *args, **kwargs):
+
−        self.callbacks.setdefault(event, []).append((callback, args, kwargs))
+
−
+
−    def emit(self, event, context=None):
+
−        for callback, args, kwargs in self.callbacks.get(event, ()):
+
−            if context is None:
+
−                callback(*args, **kwargs)
+
−            else:
+
−                callback(context, *args, **kwargs)
+
−
+
−
+
−CW_EVENT_MANAGER = CubicWebEventManager()
+
−
+
−
+
−def onevent(event, *args, **kwargs):
+
−    """decorator to ease event / callback binding
+
−
+
−    >>> from cubicweb import onevent
+
−    >>> @onevent('before-registry-reload')
+
−    ... def mycallback():
+
−    ...     print 'hello'
+
−    ...
+
−    >>>
+
−    """
+
−    def _decorator(func):
+
−        CW_EVENT_MANAGER.bind(event, func, *args, **kwargs)
+
−        return func
+
−    return _decorator
+
−
+
−
+
−def validation_error(entity, errors, substitutions=None, i18nvalues=None):
+
−    """easy way to retrieve a :class:`cubicweb.ValidationError` for an entity or eid.
+
−
+
−    You may also have 2-tuple as error keys, :func:`yams.role_name` will be
+
−    called automatically for them.
+
−
+
−    Messages in errors **should not be translated yet**, though marked for
+
−    internationalization. You may give an additional substition dictionary that
+
−    will be used for interpolation after the translation.
+
−    """
+
−    if substitutions is None:
+
−        # set empty dict else translation won't be done for backward
+
−        # compatibility reason (see ValidationError.translate method)
+
−        substitutions = {}
+
−    for key in list(errors):
+
−        if isinstance(key, tuple):
+
−            errors[rname(*key)] = errors.pop(key)
+
−    return ValidationError(getattr(entity, 'eid', entity), errors,
+
−                           substitutions, i18nvalues)
+
−
+
−
+
−# exceptions ##################################################################
+
−
+
−class ProgrammingError(Exception):
+
−    """Exception raised for errors that are related to the database's operation
+
−    and not necessarily under the control of the programmer, e.g. an unexpected
+
−    disconnect occurs, the data source name is not found, a transaction could
+
−    not be processed, a memory allocation error occurred during processing,
+
−    etc.
+
−    """