transport/mongodb: normalize URI options to lowercase and flatten single-item lists Normalize MongoDB URI option keys to lowercase and flatten single-item lists returned by uri_parser.parse_uri. This ensures that query params like replicaSet=test_rs are accessible as options['replicaset'] with a scalar value, matching existing Kombu tests and expectations. Normalization is performed before _prepare_client_options so that lowercased keys (e.g., readpreference) are properly handled.

Author: ghirailghiro

kombu/transport/mongodb.py

@@ -321,6 +321,14 @@ def _parse_uri(self, scheme='mongodb://'):
                                  if self.connect_timeout else None),
         }
         options.update(parsed['options'])
+        normalized = {}
+        for k, v in options.items():
+            val = v[0] if isinstance(v, list) and len(v) == 1 else v
+            normalized[k] = val
+            lk = k.lower()
+            if lk not in normalized:
+                normalized[lk] = val
+        options = normalized
         options = self._prepare_client_options(options)
 
         if 'tls' in options: