Add the check for columns

sdgym/synthesizers/uniform.py

@@ -17,18 +17,23 @@ def _get_trained_synthesizer(self, real_data, metadata):
         hyper_transformer = HyperTransformer()
         hyper_transformer.detect_initial_config(real_data)
         if metadata:
-            metadata_dict = metadata.to_dict()
-            supported_sdtypes = hyper_transformer._get_supported_sdtypes()
-            config = {}
-            for column in metadata_dict['columns']:
-                sdtype = metadata_dict['columns'][column]['sdtype']
-                if sdtype in supported_sdtypes:
-                    config[column] = metadata_dict['columns'][column]['sdtype']
-                else:
-                    LOGGER.info(
-                        f'Column {column} sdtype: {sdtype} is not supported, '
-                        f'defaulting to inferred type.')
-            hyper_transformer.update_sdtypes(config)
+            metadata_dict = {}
+            if isinstance(metadata, dict):
+                metadata_dict = metadata
+            else:
+                metadata_dict = metadata.to_dict()
+            if 'columns' in metadata_dict:
+                supported_sdtypes = hyper_transformer._get_supported_sdtypes()
+                config = {}
+                for column in metadata_dict['columns']:
+                    sdtype = metadata_dict['columns'][column]['sdtype']
+                    if sdtype in supported_sdtypes:
+                        config[column] = metadata_dict['columns'][column]['sdtype']
+                    else:
+                        LOGGER.info(
+                            f'Column {column} sdtype: {sdtype} is not supported, '
+                            f'defaulting to inferred type.')
+                hyper_transformer.update_sdtypes(config)
 
         # This is done to match the behavior of the synthesizer for SDGym <= 0.6.0
         columns_to_remove = [