diff --git a/swh/indexer/metadata.py b/swh/indexer/metadata.py
--- a/swh/indexer/metadata.py
+++ b/swh/indexer/metadata.py
@@ -75,6 +75,10 @@
         try:
             results = []
             for item in objects.get("raw_extrinsic_metadata", []):
+                id_ = item.get("id")
+                if not id_:
+                    self.log.warning("Missing 'id' key entry in item %r", item)
+                    continue
                 results.extend(
                     self.index(item["id"], data=RawExtrinsicMetadata.from_dict(item))
                 )