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 venusian

    18 

    19 # import interfaces

    20 from zope.component.interfaces import ComponentLookupError

    21 

    22 # import packages

    23 from pyramid.threadlocal import get_current_registry, get_current_request

    24 from zope.interface import implementedBy, providedBy

    25 

    26 

    27 def _get_registries():

    28     """Get list of component registries"""

    29     registry = get_current_registry()

    30     yield registry

    31     request = get_current_request()

    32     if (request is not None) and (request.registry != registry):

    33         yield request.registry

    34 

    35 

    36 def registered_utilities():

    37     """Get utilities registrations as generator"""

    38     for registry in _get_registries():

    39         for utility in registry.registeredUtilities():

    40             yield utility

    41 

    42 

    43 def query_utility(provided, name='', default=None):

    44     """Query utility registered with given interface"""

    45     for registry in _get_registries():

    46         utility = registry.queryUtility(provided, name, default)

    47         if utility is not None:

    48             return utility

    49     return default

    50 

    51 

    52 def get_utility(provided, name=''):

    53     """Get utility registered with given interface"""

    54     for registry in _get_registries():

    55         utility = registry.queryUtility(provided, name)

    56         if utility is not None:

    57             return utility

    58     raise ComponentLookupError(provided, name)

    59 

    60 

    61 def get_utilities_for(interface):

    62     """Get utilities registered with given interface as (name, util)"""

    63     for registry in _get_registries():

    64         for utility in registry.getUtilitiesFor(interface):

    65             yield utility

    66 

    67 

    68 def get_all_utilities_registered_for(interface):

    69     """Get list of registered utilities for given interface"""

    70     result = []

    71     for registry in _get_registries():

    72         for utilities in registry.getAllUtilitiesRegisteredFor(interface):

    73             result.extend(utilities)

    74     return result

    75 

    76 

    77 class utility_config(object):

    78     """Function or class decorator to declare a utility"""

    79 

    80     venusian = venusian

    81 

    82     def __init__(self, **settings):

    83         self.__dict__.update(settings)

    84 

    85     def __call__(self, wrapped):

    86         settings = self.__dict__.copy()

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

    88 

    89         def callback(context, name, ob):

    90             if type(ob) is type:

    91                 factory = ob

    92                 component = None

    93             else:

    94                 factory = None

    95                 component = ob

    96 

    97             provides = settings.get('provides')

    98             if provides is None:

    99                 if factory:

   100                     provides = list(implementedBy(factory))

   101                 else:

   102                     provides = list(providedBy(component))

   103                 if len(provides) == 1:

   104                     provides = provides[0]

   105                 else:

   106                     raise TypeError("Missing 'provides' argument")

   107 

   108             config = context.config.with_package(info.module)

   109             config.registry.registerUtility(component=component, factory=factory,

   110                                             provided=provides, name=settings.get('name', ''))

   111 

   112         info = self.venusian.attach(wrapped, callback, category='pyams_utility',

   113                                     depth=depth + 1)

   114 

   115         if info.scope == 'class':

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

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

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

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

   120                 settings['attr'] = wrapped.__name__

   121 

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

   123         return wrapped