feat: add support for map target type in Parquet options (#1919)

* Update format_options.py to include the newly added map target type.

The map target type creates a schema without the added key_value repeated field.

* Added tests

* add unit test

* lint

---------

Co-authored-by: Lingqing Gan <lingqing.gan@gmail.com>

google/cloud/bigquery/format_options.py

@@ -105,6 +105,21 @@ def enable_list_inference(self) -> bool:
     def enable_list_inference(self, value: bool) -> None:
         self._properties["enableListInference"] = value
 
+    @property
+    def map_target_type(self) -> str:
+        """Indicates whether to simplify the representation of parquet maps to only show keys and values."""
+
+        return self._properties.get("mapTargetType")
+
+    @map_target_type.setter
+    def map_target_type(self, value: str) -> None:
+        """Sets the map target type.
+
+        Args:
+          value: The map target type (eg ARRAY_OF_STRUCT).
+        """
+        self._properties["mapTargetType"] = value
+
     @classmethod
     def from_api_repr(cls, resource: Dict[str, bool]) -> "ParquetOptions":
         """Factory: construct an instance from a resource dict.

tests/unit/test_format_options.py

@@ -54,11 +54,17 @@ def test_from_api_repr(self):
         )
         assert not config.enum_as_string
         assert config.enable_list_inference
+        assert config.map_target_type is None
 
     def test_to_api_repr(self):
         config = self._get_target_class()()
         config.enum_as_string = True
         config.enable_list_inference = False
+        config.map_target_type = "ARRAY_OF_STRUCT"
 
         result = config.to_api_repr()
-        assert result == {"enumAsString": True, "enableListInference": False}
+        assert result == {
+            "enumAsString": True,
+            "enableListInference": False,
+            "mapTargetType": "ARRAY_OF_STRUCT",
+        }