Clean to make it run under Plone 5

* remove hard dependency to Products.Archetypes
* remove subscriber to IObjectAddedEvent; when a tile is added, there nothing on it so it makes no sense to update link integrity references
* add conditionals to allow running the code under both, Plone 4 and 5
* use a better name for the event handler
* remove all checking that is irrelevant; all of those things have to be present under Plone 4

setup.py

@@ -80,7 +80,6 @@
           'plone.tiles',
           'plone.uuid',
           'plone.z3cform',
-          'Products.Archetypes',
           'Products.CMFCore',
           'Products.CMFPlone >=4.2',
           'Products.GenericSetup',

src/collective/cover/events.py

@@ -1,16 +1,20 @@
 # -*- coding: utf-8 -*-
+from collective.cover.config import PLONE_VERSION
 from collective.cover.interfaces import ICover
 from five import grok
-from plone import api
 from plone.app.iterate.interfaces import ICheckinEvent
 from plone.app.linkintegrity.handlers import getObjectsFromLinks
-from plone.app.linkintegrity.handlers import referencedRelationship
 from plone.app.linkintegrity.parser import extractLinks
-from plone.app.linkintegrity.references import updateReferences
 from plone.app.textfield.value import RichTextValue
-from Products.Archetypes.interfaces import IReferenceable
 from zope.annotation.interfaces import IAnnotations
 
+if PLONE_VERSION.startswith('5'):
+    from plone.app.linkintegrity.handlers import updateReferences
+else:
+    from plone.app.linkintegrity.handlers import referencedRelationship
+    from plone.app.linkintegrity.references import updateReferences
+    from Products.Archetypes.interfaces import IReferenceable
+
 
 @grok.subscribe(ICover, ICheckinEvent)
 def override_object_annotations(cover, event):
@@ -35,29 +39,15 @@ def override_object_annotations(cover, event):
             old_annotations[key] = new_annotations[key]
 
 
-def modifiedCoverTile(obj, event):
-    """Ensure link integrity on Rich Text tiles.
+def update_link_integrity(obj, event):
+    """Update link integrity information on modification/removal of
+    tiles.
 
-    Keyword arguments:
-    obj -- Dexterity-based object that was modified
-    event -- event fired
+    :param obj: cover object that was modified
+    :type obj: Dexterity-based content type
+    :param event: event fired
+    :type event:
     """
-    pu = api.portal.get_tool('portal_url')
-    if pu is None:
-        # `getObjectFromLinks` is not possible without access
-        # to `portal_url`
-        return
-    rc = api.portal.get_tool('reference_catalog')
-    if rc is None:
-        # `updateReferences` is not possible without access
-        # to `reference_catalog`
-        return
-    referenceable_parent = IReferenceable(obj.context, None)
-    if referenceable_parent is None:
-        # `updateReferences` is not possible
-        # if parent object isn't referenceable
-        return
-
     refs = set()
 
     for name, value in obj.data.items():
@@ -68,4 +58,7 @@ def modifiedCoverTile(obj, event):
             links = extractLinks(value)
             refs |= getObjectsFromLinks(obj.context, links)
 
-    updateReferences(IReferenceable(obj.context), referencedRelationship, refs)
+    if PLONE_VERSION.startswith('5'):
+        updateReferences(obj.context, refs)
+    else:
+        updateReferences(IReferenceable(obj.context), referencedRelationship, refs)

src/collective/cover/subscribers.zcml

@@ -1,31 +1,24 @@
 <configure
     xmlns="http://namespaces.zope.org/zope"
     xmlns:browser="http://namespaces.zope.org/browser"
-    xmlns:zcml="http://namespaces.zope.org/zcml"
     xmlns:five="http://namespaces.zope.org/five"
-    >
+    xmlns:zcml="http://namespaces.zope.org/zcml">
 
   <!-- event handlers for updating link integrity references -->
 
   <subscriber
       for="collective.cover.tiles.base.IPersistentCoverTile
            OFS.interfaces.IObjectClonedEvent"
-      handler=".events.modifiedCoverTile"
-      />
-
-  <subscriber
-      for="collective.cover.tiles.base.IPersistentCoverTile
-           zope.lifecycleevent.interfaces.IObjectAddedEvent"
-      handler=".events.modifiedCoverTile"
+      handler=".events.update_link_integrity"
       />
 
   <subscriber
       for="collective.cover.tiles.base.IPersistentCoverTile
            zope.lifecycleevent.interfaces.IObjectModifiedEvent"
-      handler=".events.modifiedCoverTile"
+      handler=".events.update_link_integrity"
       />
 
-  <subscriber
+  <subscriber zcml:condition="not-have plone-5"
       for="collective.cover.tiles.base.IPersistentCoverTile
            zope.lifecycleevent.interfaces.IObjectRemovedEvent"
       handler="plone.app.linkintegrity.handlers.referencedObjectRemoved"