Pass CommitProperties for custom metadata due to changed api

daft/dataframe/dataframe.py

@@ -948,6 +948,18 @@ def write_deltalake(
         from daft.io._deltalake import large_dtypes_kwargs
         from daft.io.object_store_options import io_config_to_storage_options
 
+        # to ensure compatibility for deltalake<0.20
+        try:
+            from deltalake import CommitProperties
+
+            def _create_custom_metadata(metadata: Optional[Dict[str, str]]):
+                return CommitProperties(custom_metadata=custom_metadata)
+        except ImportError:
+            CommitProperties = None
+
+            def _create_custom_metadata(metadata: Optional[Dict[str, str]]):
+                return metadata
+
         if schema_mode == "merge":
             raise ValueError("Schema mode' merge' is not currently supported for write_deltalake.")
 
@@ -1093,7 +1105,12 @@ def write_deltalake(
                     sizes.append(old_actions_dict["size_bytes"][i])
 
             table._table.create_write_transaction(
-                add_actions, mode, partition_cols or [], delta_schema, None, custom_metadata
+                add_actions,
+                mode,
+                partition_cols or [],
+                delta_schema,
+                None,
+                _create_custom_metadata(custom_metadata),
             )
             table.update_incremental()