versioning: add handler for IObjectRemovedEvent to clean up versions upon deletion of a versioned object

git-svn-id: svn://svn.cy55.de/Zope3/src/loops/trunk@1720 fd906abe-77d9-0310-91a1-e0d9ade77398

versioning/README.txt

@@ -133,6 +133,24 @@ In addition it is possible to explicitly retrieve a certain version:
   '1.1'
 
 
+Deleting Versioned Resources
+============================
+
+When a version object is deleted the reference to it on the corresponding
+master object is removed.
+
+  >>> del resources['d001_1.2.txt']
+  >>> sorted(IVersionable(d001).versions)
+  ['1.1', '2.1', '2.2']
+
+When the master object of a versioned resource is deleted all version objects
+derived from it are deleted as well.
+
+  >>> del resources['d001.txt']
+  >>> sorted(resources)
+  [u'd002.txt', u'd003.txt']
+
+
 Fin de partie
 =============
 

versioning/configure.zcml

@@ -16,6 +16,12 @@
              set_schema="loops.versioning.interfaces.IVersionable" />
   </zope:class>
 
+  <zope:subscriber
+        for="loops.interfaces.IResource
+             zope.app.container.interfaces.IObjectRemovedEvent"
+        handler="loops.versioning.versionable.cleanupVersions"
+        />
+
   <!-- user interface -->
 
   <browser:page

versioning/testsetup.py

@@ -9,6 +9,7 @@ from zope.app.catalog.catalog import Catalog
 from zope.app.catalog.interfaces import ICatalog
 from zope.app.catalog.field import FieldIndex
 from zope.app.catalog.text import TextIndex
+from zope.app.container.interfaces import IObjectRemovedEvent
 
 from cybertools.relation.tests import IntIdsStub
 from cybertools.relation.registry import RelationRegistry
@@ -18,7 +19,7 @@ from cybertools.typology.interfaces import IType
 
 from loops import Loops
 from loops import util
-from loops.interfaces import IIndexAttributes
+from loops.interfaces import IResource, IIndexAttributes
 from loops.concept import Concept
 from loops.concept import IndexAttributes as ConceptIndexAttributes
 from loops.resource import Resource
@@ -26,6 +27,7 @@ from loops.resource import IndexAttributes as ResourceIndexAttributes
 from loops.knowledge.setup import SetupManager as KnowledgeSetupManager
 from loops.setup import SetupManager, addObject
 from loops.type import ConceptType, ResourceType, TypeConcept
+from loops.versioning.versionable import cleanupVersions
 
 
 class TestSite(object):
@@ -53,6 +55,9 @@ class TestSite(object):
         catalog['loops_text'] = TextIndex('text', IIndexAttributes, True)
         catalog['loops_type'] = FieldIndex('tokenForSearch', IType, False)
 
+        component.getSiteManager().registerHandler(cleanupVersions,
+                            (IResource, IObjectRemovedEvent))
+
         loopsRoot = site['loops'] = Loops()
 
         component.provideAdapter(KnowledgeSetupManager, name='knowledge')

versioning/versionable.py

@@ -163,3 +163,23 @@ class VersionableResource(object):
             name = name[:-4]
         return name + '_' + versionId + ext
 
+
+def cleanupVersions(context, event):
+    """ Called upon deletion of a resource.
+    """
+    #print 'cleaning up'
+    vContext = IVersionable(context, None)
+    if vContext is None:
+        return
+    rm = context.getLoopsRoot().getResourceManager()
+    if context == vContext.master:
+        toBeDeleted = []
+        for v in vContext.versions.values():
+            if v != context:
+                toBeDeleted.append(getName(v))
+        for name in toBeDeleted:
+            del rm[name]
+    else:
+        vId = vContext.versionId
+        vMaster = IVersionable(vContext.master)
+        del vMaster.versions[vId]