Add deletion support to importer-based datasync

rattail/datasync/consumers.py

@@ -91,7 +91,7 @@ class DataSyncImportConsumer(DataSyncConsumer):
             importer = self.importers.get(change.payload_type)
             if importer:
                 if change.deletion:
-                    raise NotImplementedError
+                    self.process_deletion(session, importer, change)
                 else:
                     self.process_change(session, importer, change)
 
@@ -113,6 +113,20 @@ class DataSyncImportConsumer(DataSyncConsumer):
         else:
             importer.create_instance(key, host_data)
 
+    def process_deletion(self, session, importer, change):
+        """
+        Attempt to invoke the importer, to delete a local record according to
+        the change involved.
+        """
+        key = self.get_deletion_key(session, change)
+        local_record = importer.get_instance(key)
+        if local_record:
+            return importer.delete_instance(local_record)
+        return False
+
+    def get_deletion_key(self, session, change):
+        return (change.payload_key,)
+
     def get_host_record(self, session, change):
         """
         You must override this, to return a host record from the given