Work in progress: new ConceptRelation implementation that uses concepts as predicates

git-svn-id: svn://svn.cy55.de/Zope3/src/loops/trunk@1091 fd906abe-77d9-0310-91a1-e0d9ade77398

README.txt

@@ -41,12 +41,15 @@ top-level loops container and a concept manager:
 Now we want to relate the second concept to the first one.
 
 In order to do this we first have to provide a relation registry. For
-testing we use a simple dummy implementation.
+testing we use a simple dummy implementation. As relationships are
+based on predicates that are themselves concepts we also need a
+default predicate concept; the default name for this is 'standard'.
 
   >>> from cybertools.relation.interfaces import IRelationRegistry
   >>> from cybertools.relation.registry import DummyRelationRegistry
   >>> from zope.app.testing import ztapi
   >>> ztapi.provideUtility(IRelationRegistry, DummyRelationRegistry())
+  >>> concepts['standard'] = Concept('Default Predicate')
 
 Now we can assign the concept c2 as a child to c1 (using the standard
 ConceptRelation):
@@ -74,8 +77,10 @@ We can now ask our concepts for their related child and parent concepts:
 
 Each concept should have a concept type; this is in fact provided by a
 relation to a special kind of concept object with the magic name 'type'.
-This type object is its own type:
+This type object is its own type. The type relations themselves are of
+a special predicate 'hasType'.
 
+  >>> concepts['hasType'] = Concept(u'Type Predicate')
   >>> concepts['type'] = Concept(u'Type')
   >>> typeObject = concepts['type']
   >>> typeObject.setConceptType(typeObject)
@@ -99,6 +104,13 @@ This type object is its own type:
   >>> cc1.getConceptType().title
   u'Topic'
 
+We get a list of types using the ConceptTypeSourceList:
+
+  >>> from loops.concept import ConceptTypeSourceList
+  >>> types = ConceptTypeSourceList(cc1)
+  >>> sorted(t.title for t in types)
+  [u'Topic', u'Type', u'Unknown Type']
+    
 Concept Views
 -------------
 
@@ -108,9 +120,6 @@ Concept Views
   >>> sorted([c.title for c in view.children()])
   [u'Zope 3']
 
-The concept view allows to get a list of terms (sort of vocabulary) that
-can be used to show the objects in a listing:
-
 The concept view allows updating the underlying context object:
 
   >>> cc3 = Concept(u'loops for Zope 3')
@@ -388,9 +397,9 @@ objects.) The source is basically a source list:
   >>> from loops.target import TargetSourceList
   >>> source = TargetSourceList(m111)
   >>> len(source)
-  8
+  1
   >>> sorted([zapi.getName(s) for s in source])
-  [u'cc1', u'cc2', u'cc3', u'cc4', u'doc1', u'topic', u'type', u'unknown']
+  [u'doc1']
 
 The form then uses a sort of browser view providing the ITerms interface
 based on this source list:

browser/common.py

@@ -27,7 +27,6 @@ from zope.app.dublincore.interfaces import ICMFDublinCore
 from zope.app.form.browser.interfaces import ITerms
 from zope.cachedescriptors.property import Lazy
 from zope.interface import implements
-#from zope.schema.vocabulary import SimpleTerm
 from zope.security.proxy import removeSecurityProxy
 
 class BaseView(object):
@@ -85,9 +84,6 @@ class LoopsTerms(object):
     
     def getTerm(self, value):
         return BaseView(value, self.request)
-        #token = self.loopsRoot.getLoopsUri(value)
-        #title = value.title or zapi.getName(value)
-        #return SimpleTerm(value, token, title)
 
     def getValue(self, token):
         return self.loopsRoot.loopsTraverse(token)

browser/concept.py

@@ -25,8 +25,10 @@ $Id$
 from zope.app import zapi
 from zope.app.catalog.interfaces import ICatalog
 from zope.app.dublincore.interfaces import ICMFDublinCore
+from zope.app.event.objectevent import ObjectCreatedEvent
 from zope.app.form.browser.interfaces import ITerms
 from zope.cachedescriptors.property import Lazy
+from zope.event import notify
 from zope.interface import implements
 from zope.publisher.interfaces import BadRequest
 from zope import schema
@@ -90,6 +92,8 @@ class ConceptView(BaseView):
         concept = Concept(title)
         container = self.loopsRoot.getConceptManager()
         container[name] = concept
+        # TODO: notify ObjectCreatedEvent() (?)
+        #notify(ObjectCreatedEvent(removeSecurityProxy(concept)))
         assignAs = self.request.get('assignAs', 'child')
         if assignAs == 'child':
             self.context.assignChild(removeSecurityProxy(concept))

concept.py

@@ -35,7 +35,7 @@ from persistent import Persistent
 from cybertools.relation import DyadicRelation
 from cybertools.relation.registry import getRelations
 from cybertools.relation.registry import getRelationSingle, setRelationSingle
-from cybertools.relation.interfaces import IRelationRegistry
+from cybertools.relation.interfaces import IRelationRegistry, IRelatable
 
 from interfaces import IConcept, IConceptRelation, IConceptView
 from interfaces import IConceptManager, IConceptManagerContained
@@ -50,12 +50,18 @@ class ConceptRelation(DyadicRelation):
     """
     implements(IConceptRelation)
 
+    def __init__(self, first, second, predicate=None):
+        super(ConceptRelation, self).__init__(first, second)
+        if predicate is None:
+            context = first is not None and first or second
+            cm = context.getLoopsRoot().getConceptManager()
+            predicate = cm.getDefaultPredicate()
+        self.predicate = predicate
 
-class TypeRelation(DyadicRelation):
+    def getPredicateName(self):
-    """ A special relation between two concepts, the parent specifying
+        baseName = super(ConceptRelation, self).getPredicateName()
-        the type of the child.
+        id = zapi.getUtility(IRelationRegistry).getUniqueIdForObject(self.predicate)
-    """
+        return '.'.join((baseName, str(id)))
-    implements(IConceptRelation)
 
 
 class ResourceRelation(DyadicRelation):
@@ -68,7 +74,7 @@ class ResourceRelation(DyadicRelation):
     
 class Concept(Contained, Persistent):
 
-    implements(IConcept, IConceptManagerContained)
+    implements(IConcept, IConceptManagerContained, IRelatable)
 
     proxyInterface = IConceptView
     
@@ -78,11 +84,16 @@ class Concept(Contained, Persistent):
     title = property(getTitle, setTitle)
 
     def getConceptType(self):
-        rel = getRelationSingle(self, TypeRelation)
+        cm = self.getLoopsRoot().getConceptManager()
-        return rel and rel.second or None
+        typeRelation = ConceptRelation(None, self, cm.getTypePredicate())
+        rel = getRelationSingle(self, typeRelation, forSecond=True)
+        return rel and rel.first or None
     def setConceptType(self, concept):
         if self.getConceptType() != concept:
-            setRelationSingle(TypeRelation(self, removeSecurityProxy(concept)))
+            cm = self.getLoopsRoot().getConceptManager()
+            typeRelation = ConceptRelation(removeSecurityProxy(concept), self,
+                                           cm.getTypePredicate())
+            setRelationSingle(typeRelation, forSecond=True)
     conceptType = property(getConceptType, setConceptType)
 
     def __init__(self, title=u''):
@@ -95,14 +106,14 @@ class Concept(Contained, Persistent):
 
     def getChildren(self, relationships=None):
         if relationships is None:
-            relationships = [ConceptRelation]
+            relationships = [ConceptRelation(self, None)]
         rels = getRelations(first=self, relationships=relationships)
         return [r.second for r in rels]
         # TODO: sort...
 
     def getParents(self, relationships=None):
         if relationships is None:
-            relationships = [ConceptRelation]
+            relationships = [ConceptRelation(None, self)]
         rels = getRelations(second=self, relationships=relationships)
         return [r.first for r in rels]
 
@@ -117,7 +128,7 @@ class Concept(Contained, Persistent):
 
     def deassignChildren(self, concept, relationships=None):
         if relationships is None:
-            relationships = [ConceptRelation]
+            relationships = [ConceptRelation(self, None)]
         registry = zapi.getUtility(IRelationRegistry)
         relations = []
         for rs in relationships:
@@ -159,9 +170,28 @@ class ConceptManager(BTreeContainer):
 
     implements(IConceptManager, ILoopsContained)
 
+    typeConcept = None
+    typePredicate = None
+    defaultPredicate = None
+
     def getLoopsRoot(self):
         return zapi.getParent(self)
 
+    def getTypePredicate(self):
+        if self.typePredicate is None:
+            self.typePredicate = self['hasType']
+        return self.typePredicate
+
+    def getTypeConcept(self):
+        if self.typeConcept is None:
+            self.typeConcept = self['type']
+        return self.typeConcept
+
+    def getDefaultPredicate(self):
+        if self.defaultPredicate is None:
+            self.defaultPredicate = self['standard']
+        return self.defaultPredicate
+
     def getViewManager(self):
         return self.getLoopsRoot().getViewManager()
     
@@ -202,10 +232,12 @@ class ConceptTypeSourceList(object):
     @Lazy
     def conceptTypes(self):
         result = []
-        typeObject = self.concepts.get('type')
+        cm = self.concepts
+        typeObject = cm.getTypeConcept()
         unknownType = self.concepts.get('unknown')
         if typeObject is not None:
-            types = typeObject.getParents((TypeRelation,))
+            typeRelation = ConceptRelation(None, typeObject, cm.getTypePredicate())
+            types = typeObject.getChildren((typeRelation,))
             if typeObject not in types:
                 result.append(typeObject)
             if unknownType is not None and unknownType not in types:

configure.zcml

@@ -74,6 +74,10 @@
         permission="zope.ManageContent"
         interface="zope.app.container.interfaces.IWriteContainer" />
 
+    <require
+        permission="zope.View"
+        attributes="getTypePredicate getDefaultPredicate getTypeConcept" />
+  
   </content>
 
   <interface

interfaces.py

@@ -141,6 +141,17 @@ class IConceptManager(ILoopsObject, IContainer):
     """
     contains(IConcept)
 
+    def getTypePredicate():
+        """ Return the concept that provides the type predicate.
+        """
+
+    def getTypeConcept():
+        """ Return the concept that provides the type object.
+        """
+
+    def getDefaultPredicate():
+        """ Return the concept that provides the default (standard) predicate.
+        """
 
 class IConceptManagerContained(Interface):
     containers(IConceptManager)

resource.py

@@ -30,6 +30,7 @@ from zope.interface import implements
 from persistent import Persistent
 from cStringIO import StringIO
 from cybertools.relation.registry import getRelations
+from cybertools.relation.interfaces import IRelatable
 
 from interfaces import IResource
 from interfaces import IDocument, IDocumentSchema, IDocumentView
@@ -40,7 +41,7 @@ from interfaces import ILoopsContained
 
 class Resource(Contained, Persistent):
 
-    implements(IResource, IResourceManagerContained)
+    implements(IResource, IResourceManagerContained, IRelatable)
 
     _title = u''
     def getTitle(self): return self._title

target.py

@@ -112,7 +112,10 @@ class TargetSourceList(object):
         self.context = removeSecurityProxy(context)
         root = self.context.getLoopsRoot()
         self.resources = root.getResourceManager()
-        self.concepts = root.getConceptManager()
+        # concepts will only be included when we have some really
+        # queryable source with a corresponding user interface:
+        #self.concepts = root.getConceptManager()
+        self.concepts = {}
 
     def __iter__(self):
         for obj in self.resources.values():

view.py

@@ -36,7 +36,7 @@ from zope.security.proxy import removeSecurityProxy
 from persistent import Persistent
 from cybertools.relation import DyadicRelation
 from cybertools.relation.registry import getRelations
-from cybertools.relation.interfaces import IRelationRegistry
+from cybertools.relation.interfaces import IRelationRegistry, IRelatable
 
 from interfaces import IView, INode, INodeConfigSchema
 from interfaces import IViewManager, INodeContained
@@ -46,7 +46,7 @@ from interfaces import ITargetRelation
 
 class View(object):
 
-    implements(IView, INodeContained)
+    implements(IView, INodeContained, IRelatable)
 
     _title = u''
     def getTitle(self): return self._title