307     # .accepts handling utilities #############################################

   308     

   309     accepts = ('Any',)

   310 

   311     @classmethod

   312     def accept_rset(cls, req, rset, row, col):

   313         """apply the following rules:

   314         * if row is None, return the sum of values returned by the method

   315           for each entity's type in the result set. If any score is 0,

   316           return 0.

   317         * if row is specified, return the value returned by the method with

   318           the entity's type of this row

   319         """

   320         if row is None:

   321             score = 0

   322             for etype in rset.column_types(0):

   323                 accepted = cls.accept(req.user, etype)

   324                 if not accepted:

   325                     return 0

   326                 score += accepted

   327             return score

   328         return cls.accept(req.user, rset.description[row][col or 0])

   329         

   330     @classmethod

   331     def accept(cls, user, etype):

   332         """score etype, returning better score on exact match"""

   333         if 'Any' in cls.accepts:

   334             return 1

   335         eschema = cls.schema.eschema(etype)

   336         matching_types = [e.type for e in eschema.ancestors()]

   337         matching_types.append(etype)

   338         for index, basetype in enumerate(matching_types):

   339             if basetype in cls.accepts:

   340                 return 2 + index

   341         return 0

   342     

   343     # .rtype  handling utilities ##############################################

   344     

   345     @classmethod

   346     def relation_possible(cls, etype):

   347         """tell if a relation with etype entity is possible according to 

   348         mixed class'.etype, .rtype and .target attributes

   349 

   350         XXX should probably be moved out to a function

   351         """

   352         schema = cls.schema

   353         rtype = cls.rtype

   354         eschema = schema.eschema(etype)

   355         if hasattr(cls, 'role'):

   356             role = cls.role

   357         elif cls.target == 'subject':

   358             role = 'object'

   359         else:

   360             role = 'subject'

   361         # check if this relation is possible according to the schema

   362         try:

   363             if role == 'object':

   364                 rschema = eschema.object_relation(rtype)

   365             else:

   366                 rschema = eschema.subject_relation(rtype)

   367         except KeyError:

   368             return False            

   369         if hasattr(cls, 'etype'):

   370             letype = cls.etype

   371             try:

   372                 if role == 'object':

   373                     return etype in rschema.objects(letype)

   374                 else:

   375                     return etype in rschema.subjects(letype)

   376             except KeyError, ex:

   377                 return False

   378         return True

   379 

   380     

   381     # XXX deprecated (since 2.43) ##########################

   382     

   383     @obsolete('use req.datadir_url')

   384     def datadir_url(self):

   385         """return url of the application's data directory"""

   386         return self.req.datadir_url

   387 

   388     @obsolete('use req.external_resource()')

   389     def external_resource(self, rid, default=_MARKER):

   390         return self.req.external_resource(rid, default)

   391