1 #

     2 # Copyright (c) 2008-2015 Thierry Florac <tflorac AT ulthar.net>

     3 # All Rights Reserved.

     4 #

     5 # This software is subject to the provisions of the Zope Public License,

     6 # Version 2.1 (ZPL).  A copy of the ZPL should accompany this distribution.

     7 # THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED

     8 # WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

     9 # WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS

    10 # FOR A PARTICULAR PURPOSE.

    11 #

    12 

    13 __docformat__ = 'restructuredtext'

    14 

    15 

    16 # import standard library

    17 import logging

    18 logger = logging.getLogger('PyAMS (utils)')

    19 

    20 import venusian

    21 

    22 # import interfaces

    23 from zope.schema.interfaces import IVocabularyFactory

    24 

    25 # import packages

    26 from zope.interface import directlyProvides

    27 from zope.schema.vocabulary import getVocabularyRegistry

    28 

    29 

    30 class vocabulary_config:

    31     """Class decorator to define a vocabulary

    32 

    33     :param str name: name of the registered vocabulary

    34 

    35     This is, for example, how a vocabulary of registered ZEO connections utilities is created:

    36 

    37     .. code-block:: python

    38 

    39         from pyams_utils.interfaces.zeo import IZEOConnection

    40 

    41         from pyams_utils.registry import get_utilities_for

    42         from pyams_utils.vocabulary import vocabulary_config

    43         from zope.schema.vocabulary import SimpleTerm, SimpleVocabulary

    44 

    45         @vocabulary_config(name='PyAMS ZEO connections')

    46         class ZEOConnectionVocabulary(SimpleVocabulary):

    47             '''ZEO connections vocabulary'''

    48 

    49             def __init__(self, context=None):

    50                 terms = [SimpleTerm(name, title=util.name) for name, util in get_utilities_for(IZEOConnection)]

    51                 super(ZEOConnectionVocabulary, self).__init__(terms)

    52 

    53     You can then use such a vocabulary in any schema field:

    54 

    55     .. code-block:: python

    56 

    57         from zope.interface import Interface

    58         from zope.schema import Choice

    59 

    60         class MySchema(Interface):

    61             '''Custom schema interface'''

    62 

    63             zeo_connection_name = Choice(title='ZEO connection name',

    64                                          description='Please select a registered ZEO connection',

    65                                          vocabulary='PyAMS ZEO connections',

    66                                          required=False)

    67     """

    68 

    69     venusian = venusian

    70 

    71     def __init__(self, name, **settings):

    72         self.name = name

    73         self.__dict__.update(settings)

    74 

    75     def __call__(self, wrapped):

    76         settings = self.__dict__.copy()

    77         depth = settings.pop('_depth', 0)

    78 

    79         def callback(context, name, ob):

    80             logger.debug('Registering class {0} as vocabulary with name "{1}"'.format(str(ob), self.name))

    81             directlyProvides(ob, IVocabularyFactory)

    82             getVocabularyRegistry().register(self.name, ob)

    83 

    84         info = self.venusian.attach(wrapped, callback, category='pyams_vocabulary',

    85                                     depth=depth + 1)

    86 

    87         if info.scope == 'class':

    88             # if the decorator was attached to a method in a class, or

    89             # otherwise executed at class scope, we need to set an

    90             # 'attr' into the settings if one isn't already in there

    91             if settings.get('attr') is None:

    92                 settings['attr'] = wrapped.__name__

    93 

    94         settings['_info'] = info.codeinfo  # fbo "action_method"

    95         return wrapped