ResourceGroup optional, because it is removed in recent versions of C…

…KAN.

ckanext/archiver/model.py

@@ -142,16 +142,15 @@ def create(cls, resource_id):
         c.resource_id = resource_id
 
         # Find the package_id for the resource.
-        q = """
-            SELECT P.id from package P
-            INNER JOIN resource_group RG ON RG.package_id = P.id
-            INNER JOIN resource R ON R.resource_group_id = RG.id
-            WHERE R.id = '%s';
-        """
-        row = model.Session.execute(q % c.resource_id).first()
-        if not row or not row[0]:
-            raise Exception("Missing dataset")
-        c.package_id = row[0]
+        dataset = model.Session.query(model.Package)
+        if hasattr(model, 'ResourceGroup'):
+            # earlier CKANs had ResourceGroup
+            dataset = dataset.join(model.ResourceGroup)
+        dataset = dataset \
+            .join(model.Resource) \
+            .filter_by(id=resource_id) \
+            .one()
+        c.package_id = dataset.id
         return c
 
     @property

ckanext/archiver/plugin.py

@@ -47,7 +47,11 @@ def update_config(self, config):
 
 def create_archiver_resource_task(resource, queue):
     from pylons import config
-    package = resource.resource_group.package
+    if hasattr(model, 'ResourceGroup'):
+        # earlier CKANs had ResourceGroup
+        package = resource.resource_group.package
+    else:
+        package = resource.package
     task_id = '%s/%s/%s' % (package.name, resource.id[:4], make_uuid()[:4])
     ckan_ini_filepath = os.path.abspath(config['__file__'])
     celery.send_task('archiver.update_resource', args=[ckan_ini_filepath, resource.id, queue],