parquet retain band labels if possible

Open-EO/openeo-geopyspark-driver#723

Author: jdries

openeo_driver/save_result.py

@@ -564,9 +564,12 @@ def to_geoparquet(self, destination: Optional[str] = None) -> str:
                 n_band_values = len(band_values)
                 flattened.append((timestamp, feature_index, *band_values))
 
+        band_names = [f"band_{i}" for i in range(n_band_values)]
+        if self._metadata is not None and self._metadata.has_band_dimension() and len(band_names) == len(self._metadata.bands):
+            band_names = self._metadata.band_names
+
         stats = pd.DataFrame.from_records(flattened,
-                                          columns=['date', 'feature_index'] + [f"band_{i}" for i in
-                                                                               range(n_band_values)])
+                                          columns=['date', 'feature_index'] + band_names)
 
         # TODO: support other geometry types?
         if not isinstance(self._regions, DriverVectorCube):