1 # copyright 2003-2012 LOGILAB S.A. (Paris, FRANCE), all rights reserved.

     2 # contact http://www.logilab.fr/ -- mailto:contact@logilab.fr

     3 #

     4 # This file is part of CubicWeb.

     5 #

     6 # CubicWeb is free software: you can redistribute it and/or modify it under the

     7 # terms of the GNU Lesser General Public License as published by the Free

     8 # Software Foundation, either version 2.1 of the License, or (at your option)

     9 # any later version.

    10 #

    11 # CubicWeb is distributed in the hope that it will be useful, but WITHOUT

    12 # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS

    13 # FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more

    14 # details.

    15 #

    16 # You should have received a copy of the GNU Lesser General Public License along

    17 # with CubicWeb.  If not, see <http://www.gnu.org/licenses/>.

    18 """

    19 

    20 The `AppObject` class

    21 ---------------------

    22 

    23 The AppObject class is the base class for all dynamically loaded objects

    24 (application objects) accessible through the vregistry.

    25 

    26 We can find a certain number of attributes and methods defined in this class and

    27 common to all the application objects.

    28 

    29 """

    30 __docformat__ = "restructuredtext en"

    31 

    32 from logging import getLogger

    33 

    34 from logilab.common.deprecation import deprecated, class_renamed

    35 from logilab.common.logging_ext import set_log_methods

    36 

    37 # first line imports for bw compat

    38 from logilab.common.registry import (objectify_predicate, traced_selection, Predicate,

    39                                      RegistrableObject, yes)

    40 

    41 

    42 objectify_selector = deprecated('[3.15] objectify_selector has been '

    43                                 'renamed to objectify_predicates in '

    44                                 'logilab.common.registry')(objectify_predicate)

    45 traced_selection = deprecated('[3.15] traced_selection has been '

    46                               'moved to logilab.common.registry')(traced_selection)

    47 Selector = class_renamed('Selector', Predicate,

    48                          '[3.15] Selector has been renamed to Predicate '

    49                          'in logilab.common.registry')

    50 

    51 @deprecated('[3.15] lltrace decorator can now be removed')

    52 def lltrace(func):

    53     return func

    54 

    55 # the base class for all appobjects ############################################

    56 

    57 class AppObject(RegistrableObject):

    58     """This is the base class for CubicWeb application objects which are

    59     selected in a request context.

    60 

    61     The following attributes should be set on concrete appobject classes:

    62 

    63     At selection time, the following attributes are set on the instance:

    64 

    65     :attr:`_cw`

    66       current request

    67     :attr:`cw_extra_kwargs`

    68       other received arguments

    69 

    70     And also the following, only if `rset` is found in arguments (in which case

    71     rset/row/col will be removed from `cwextra_kwargs`):

    72 

    73     :attr:`cw_rset`

    74       context result set or None

    75 

    76     :attr:`cw_row`

    77       if a result set is set and the context is about a particular cell in the

    78       result set, and not the result set as a whole, specify the row number we

    79       are interested in, else None

    80 

    81     :attr:`cw_col`

    82       if a result set is set and the context is about a particular cell in the

    83       result set, and not the result set as a whole, specify the col number we

    84       are interested in, else None

    85 

    86 

    87     .. Note::

    88 

    89       * do not inherit directly from this class but from a more specific class

    90         such as `AnyEntity`, `EntityView`, `AnyRsetView`, `Action`...

    91 

    92     """

    93     __select__ = yes()

    94 

    95     @classmethod

    96     def __registered__(cls, registry):

    97         """called by the registry when the appobject has been registered.

    98 

    99         It must return the object that will be actually registered (this may be

   100         the right hook to create an instance for example). By default the

   101         appobject is returned without any transformation.

   102         """

   103         pdefs = getattr(cls, 'cw_property_defs', {})

   104         for propid, pdef in pdefs.items():

   105             pdef = pdef.copy() # may be shared

   106             pdef['default'] = getattr(cls, propid, pdef['default'])

   107             pdef['sitewide'] = getattr(cls, 'site_wide', pdef.get('sitewide'))

   108             registry.vreg.register_property(cls._cwpropkey(propid), **pdef)

   109         assert callable(cls.__select__), cls

   110         return cls

   111 

   112     def __init__(self, req, **extra):

   113         super(AppObject, self).__init__()

   114         self._cw = req

   115         try:

   116             self.cw_rset = extra.pop('rset')

   117             self.cw_row = extra.pop('row', None)

   118             self.cw_col = extra.pop('col', None)

   119         except KeyError:

   120             pass

   121         self.cw_extra_kwargs = extra

   122 

   123     # persistent class properties ##############################################

   124     #

   125     # optional `cw_property_defs` dict on a class defines available persistent

   126     # properties for this class:

   127     #

   128     # * key: id of the property (the actual CWProperty key is build using

   129     #        <registry name>.<obj id>.<property id>

   130     # * value: tuple (property type, vocabfunc, default value, property description)

   131     #         possible types are those used by `logilab.common.configuration`

   132     #

   133     # notice that when it exists multiple objects with the same id (adaptation,

   134     # overriding) only the first encountered definition is considered, so those

   135     # objects can't try to have different default values for instance.

   136     #

   137     # you can then access to a property value using self.cw_propval, where self

   138     # is an instance of class

   139 

   140     @classmethod

   141     def _cwpropkey(cls, propid):

   142         """return cw property key for the property of the given id for this

   143         class

   144         """

   145         return '%s.%s.%s' % (cls.__registry__, cls.__regid__, propid)

   146 

   147     def cw_propval(self, propid):

   148         """return cw property value associated to key

   149 

   150         <cls.__registry__>.<cls.id>.<propid>

   151         """

   152         return self._cw.property_value(self._cwpropkey(propid))

   153 

   154     # these are overridden by set_log_methods below

   155     # only defining here to prevent pylint from complaining

   156     info = warning = error = critical = exception = debug = lambda msg,*a,**kw: None

   157 

   158 set_log_methods(AppObject, getLogger('cubicweb.appobject'))

   159 

   160 # defined here to avoid warning on usage on the AppObject class

   161 yes = deprecated('[3.15] yes has been moved to logilab.common.registry')(yes)