fixes json serialization error when adding catalog entries

https://pulp.plan.io/issues/2012
fixes #2012

plugins/pulp_rpm/plugins/catalogers/yum.py

@@ -6,7 +6,6 @@
 from pulp.server.content.sources import descriptor
 
 from pulp_rpm.common import ids
-from pulp_rpm.plugins.db import models
 from pulp_rpm.plugins.importers.yum.repomd.metadata import MetadataFiles
 from pulp_rpm.plugins.importers.yum.repomd import primary, nectar_factory
 from pulp_rpm.plugins.importers.yum.repomd import packages
@@ -51,7 +50,7 @@ def _add_packages(conduit, base_url, md_files):
             for model in _packages:
                 unit_key = model.unit_key
                 url = urljoin(base_url, model.download_path)
-                conduit.add_entry(models.RPM._content_type_id, unit_key, url)
+                conduit.add_entry(model._content_type_id, unit_key, url)
         finally:
             fp.close()
 

plugins/test/unit/plugins/catalogers/test_yum.py

@@ -90,6 +90,19 @@ def test_refresh(self, mock_add):
                     entry['unit_key'],
                     self._normalized(entry['url'])))
 
+    @patch('pulp.server.managers.content.catalog.ContentCatalogManager.add_entry')
+    def test_json_serializable(self, mock_add):
+        """
+        ensure the arguments are json serializable
+        see https://pulp.plan.io/issues/2012
+        """
+        url = 'file://%s/' % self.tmp_dir
+        conduit = CatalogerConduit(SOURCE_ID, EXPIRES)
+        cataloger = YumCataloger()
+        cataloger.refresh(conduit, {}, url)
+        for call in mock_add.call_args_list:
+            json.dumps(call)
+
     @patch('pulp_rpm.plugins.catalogers.yum.descriptor')
     def test_nectar_config(self, fake_descriptor):
         config = Mock()