Prepare NPM references and mutation API

tests/test_object_normalizer.py

@@ -6,6 +6,7 @@ from dns_sync.adapters import (
     DNS_RECORDS,
     PROXY_HOSTS,
     DiscoveredObject,
+    ObjectReference,
 )
 from dns_sync.object_normalizer import (
     normalize_discovered_object,
@@ -83,6 +84,13 @@ class ProxyHostNormalizationTests(unittest.TestCase):
                 "ssl_forced": 1,
                 "enabled": True,
             },
+            references=(
+                ObjectReference(
+                    relation="certificate",
+                    object_type=CERTIFICATES,
+                    local_key="67",
+                ),
+            ),
         )
 
         normalized = normalize_discovered_object(discovered)
@@ -97,9 +105,23 @@ class ProxyHostNormalizationTests(unittest.TestCase):
         )
         self.assertEqual(normalized.payload["forward_scheme"], "http")
         self.assertEqual(normalized.payload["forward_port"], 8080)
+        self.assertNotIn(
+            "certificate_local_key",
+            normalized.payload,
+        )
+        self.assertNotIn(
+            "certificate_id",
+            normalized.payload,
+        )
         self.assertEqual(
-            normalized.payload["certificate_local_key"],
-            "67",
+            normalized.references,
+            (
+                ObjectReference(
+                    relation="certificate",
+                    object_type=CERTIFICATES,
+                    local_key="67",
+                ),
+            ),
         )
         self.assertTrue(normalized.payload["ssl_forced"])
         self.assertTrue(normalized.payload["enabled"])