From d36226b443f30cad4b70f6b8a881cb0066945b6b Mon Sep 17 00:00:00 2001
From: Martin Burchell <martinb@aptivate.org>
Date: Mon, 13 Jun 2016 17:48:44 +0100
Subject: [PATCH] Purge dataset relationships

---
 ckan/logic/action/delete.py            |  7 +++++++
 ckan/tests/logic/action/test_delete.py | 24 ++++++++++++++++++++++++
 2 files changed, 31 insertions(+)

diff --git a/ckan/logic/action/delete.py b/ckan/logic/action/delete.py
index 87f9050a4d1..fe4300a2ef7 100644
--- a/ckan/logic/action/delete.py
+++ b/ckan/logic/action/delete.py
@@ -117,6 +117,8 @@ def dataset_purge(context, data_dict):
     :type id: string
 
     '''
+    from sqlalchemy import or_
+
     model = context['model']
     id = _get_or_bust(data_dict, 'id')
 
@@ -134,6 +136,11 @@ def dataset_purge(context, data_dict):
         for m in members.all():
             m.purge()
 
+    for r in model.Session.query(model.PackageRelationship).filter(
+            or_(model.PackageRelationship.subject_package_id == pkg.id,
+                model.PackageRelationship.object_package_id == pkg.id)).all():
+        r.purge()
+
     pkg = model.Package.get(id)
     # no new_revision() needed since there are no object_revisions created
     # during purge
diff --git a/ckan/tests/logic/action/test_delete.py b/ckan/tests/logic/action/test_delete.py
index 94b750a8ff2..ad9eba3ab90 100644
--- a/ckan/tests/logic/action/test_delete.py
+++ b/ckan/tests/logic/action/test_delete.py
@@ -451,6 +451,30 @@ def test_purged_dataset_leaves_no_trace_in_the_model(self):
         # No Revision objects were purged or created
         assert_equals(num_revisions_after - num_revisions_before, 0)
 
+    def test_purged_dataset_removed_from_relationships(self):
+        child = factories.Dataset()
+        parent = factories.Dataset()
+        grandparent = factories.Dataset()
+
+        helpers.call_action('package_relationship_create',
+                            subject=child['id'],
+                            type='child_of',
+                            object=parent['id'])
+
+        helpers.call_action('package_relationship_create',
+                            subject=parent['id'],
+                            type='child_of',
+                            object=grandparent['id'])
+
+        assert_equals(len(
+            model.Session.query(model.PackageRelationship).all()), 2)
+
+        helpers.call_action('dataset_purge',
+                            context={'ignore_auth': True},
+                            id=parent['name'])
+
+        assert_equals(model.Session.query(model.PackageRelationship).all(), [])
+
     def test_missing_id_returns_error(self):
         assert_raises(logic.ValidationError,
                       helpers.call_action, 'dataset_purge')