Work in progress: reorganized relation classes; some preliminary work on views

git-svn-id: svn://svn.cy55.de/Zope3/src/loops/trunk@849 fd906abe-77d9-0310-91a1-e0d9ade77398

README.txt

@@ -89,7 +89,7 @@ We can associate a resource with a concept by assigning it to the concept:
   [<loops.resource.Document ...>]
 
 The resource also provides access to the associated concepts (or views, see
-below):
+below) via the getClients() method:
 
   >>> conc = zope_info.getClients()
   >>> len(conc)
@@ -122,5 +122,9 @@ menu that may contain other nodes as menu items:
   >>> m112.description
   u''
 
-We can associate a node with a concept or directly with a resource:
+We can associate a node with a concept or directly with a resource via the
+view class's target attribute:
+
+  >>> m111.target = zope_info
+  >>> m112.target = zope3
 

concept.py

@@ -17,7 +17,7 @@
 #
 
 """
-Definition of the Concept class.
+Definition of the Concept and related classes.
 
 $Id$
 """
@@ -34,9 +34,22 @@ from cybertools.relation.registry import IRelationsRegistry, getRelations
 from interfaces import IConcept
 from interfaces import IConceptManager, IConceptManagerContained
 from interfaces import ILoopsContained
-from relations import ConceptRelation, ConceptResourceRelation
 
 
+# relation classes
+
+class ConceptRelation(DyadicRelation):
+    """ A relation between concept objects.
+    """
+
+
+class ResourceRelation(DyadicRelation):
+    """ A relation between a concept and a resource object.
+    """
+
+
+# concept
+    
 class Concept(Contained, Persistent):
 
     implements(IConcept, IConceptManagerContained)
@@ -71,6 +84,8 @@ class Concept(Contained, Persistent):
         # TODO (?): avoid duplicates
 
     def deassignConcept(self, concept, relationships=None):
+        if relationships is None:
+            relationships = [ConceptRelation]
         registry = zapi.getUtility(IRelationsRegistry)
         relations = registry.query(first=self, second=concept,
                                    relationships=relationships)
@@ -81,17 +96,19 @@ class Concept(Contained, Persistent):
 
     def getResources(self, relationships=None):
         if relationships is None:
-            relationships = [ConceptResourceRelation]
+            relationships = [ResourceRelation]
         rels = getRelations(first=self, relationships=relationships)
         return [r.second for r in rels]
         # TODO: sort...
 
-    def assignResource(self, resource, relationship=ConceptResourceRelation):
+    def assignResource(self, resource, relationship=ResourceRelation):
         registry = zapi.getUtility(IRelationsRegistry)
         registry.register(relationship(self, resource))
         # TODO (?): avoid duplicates
 
     def deassignResource(self, resource, relationships=None):
+        if relationships is None:
+            relationships = [ResourceRelation]
         registry = zapi.getUtility(IRelationsRegistry)
         relations = registry.query(first=self, second=resource,
                                    relationships=relationships)
@@ -99,6 +116,8 @@ class Concept(Contained, Persistent):
             registry.unregister(relation)
 
 
+# concept manager
+            
 class ConceptManager(BTreeContainer):
 
     implements(IConceptManager, ILoopsContained)

interfaces.py

@@ -22,7 +22,7 @@ loops interface definitions.
 $Id$
 """
 
-from zope.interface import Interface
+from zope.interface import Interface, Attribute
 from zope.i18nmessageid import MessageFactory
 from zope import schema
 from zope.app.container.constraints import contains, containers
@@ -168,10 +168,8 @@ class IView(Interface):
         default=u'',
         required=False)
 
-    def getConcepts():
+    target = Attribute('Target object that is referenced by this view')
-        """ Return an ordered sequence of concepts referenced by this view.
+    
-        """
-
 
 class INode(IView):
     """ A node is a view that may contain other views, thus building a

relations.py

@@ -1,49 +0,0 @@
-#
-#  Copyright (c) 2005 Helmut Merz helmutm@cy55.de
-#
-#  This program is free software; you can redistribute it and/or modify
-#  it under the terms of the GNU General Public License as published by
-#  the Free Software Foundation; either version 2 of the License, or
-#  (at your option) any later version.
-#
-#  This program 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 General Public License for more details.
-#
-#  You should have received a copy of the GNU General Public License
-#  along with this program; if not, write to the Free Software
-#  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
-#
-
-"""
-Definition of relation classes.
-
-$Id$
-"""
-
-from zope.app import zapi
-from zope.interface import implements
-
-from cybertools.relation import DyadicRelation
-
-
-class ConceptRelation(DyadicRelation):
-    """ A relation between concept objects.
-    """
-
-
-class ConceptResourceRelation(DyadicRelation):
-    """ A relation between a concept and a resource object.
-    """
-
-
-class ViewConceptRelation(DyadicRelation):
-    """ A relation between a view and a concept object.
-    """
-
-
-class ViewResourceRelation(DyadicRelation):
-    """ A relation between a view and a resource object.
-    """
-

view.py

@@ -28,6 +28,8 @@ from zope.app.container.contained import Contained
 from zope.app.container.ordered import OrderedContainer
 from zope.interface import implements
 from persistent import Persistent
+from cybertools.relation import DyadicRelation
+from cybertools.relation.registry import IRelationsRegistry, getRelations
 
 from interfaces import IView, INode
 from interfaces import IViewManager, INodeContained
@@ -48,13 +50,32 @@ class View(object):
     def setDescription(self, description): self._description = description
     description = property(getDescription, setDescription)
 
+    def getTarget(self):
+        rels = getRelations(first=self)
+        if len(rels) == 0:
+            return None
+        if len(rels) > 1:
+            raise ValueError, 'There may be only one target for a View object.'
+        return rels.next().second
+
+    def setTarget(self, target):
+        return
+        registry = zapi.getUtility(IRelationsRegistry)
+        rels = registry.query(first=self)
+        if len(rels) > 0:
+            if rels[0].second != target:
+                registry.unregister(target)
+        else:
+            rel = relationship(self, concept)
+            registry.register(rel)
+
+    target = property(getTarget, setTarget)
+
     def __init__(self, title=u'', description=u''):
         self.title = title
         self.description = description
         super(View, self).__init__()
 
-    def getConcepts(self):
-        return []
 
 
 class Node(View, OrderedContainer):
@@ -67,3 +88,8 @@ class ViewManager(BTreeContainer):
     implements(IViewManager, ILoopsContained)
 
 
+class TargetRelation(DyadicRelation):
+    """ A relation between a view and a concept or resource object.
+    """
+
+