Merge pull request #3 from datopian/fix/harvest-resource-delete

Fixes  'cannot concatenate ‘str’ and ‘NoneType’ objects' error on deleting dataset from a JSON source

ckanext/dcat/harvesters/_json.py

@@ -165,11 +165,8 @@ def gather_stage(self, harvest_job):
                 guid=guid, job=harvest_job,
                 package_id=guid_to_package_id[guid],
                 extras=[HarvestObjectExtra(key='status', value='delete')])
-            ids.append(obj.id)
-            model.Session.query(HarvestObject).\
-                filter_by(guid=guid).\
-                update({'current': False}, False)
             obj.save()
+            ids.append(obj.id)
 
         return ids
 
@@ -197,6 +194,11 @@ def import_stage(self, harvest_object):
             log.info('Deleted package {0} with guid {1}'
                      .format(harvest_object.package_id, harvest_object.guid))
 
+            model.Session.query(HarvestObject).\
+                filter_by(guid=harvest_object.guid).\
+                filter_by(current=True).\
+                update({'current': False}, False)
+
             return True
 
         if harvest_object.content is None: