feat: add support for checking uuid4 fields (#1972)

gapic/schema/wrappers.py

@@ -39,6 +39,7 @@
 from google.api import annotations_pb2      # type: ignore
 from google.api import client_pb2
 from google.api import field_behavior_pb2
+from google.api import field_info_pb2
 from google.api import http_pb2
 from google.api import resource_pb2
 from google.api import routing_pb2
@@ -307,6 +308,17 @@ def required(self) -> bool:
         return (field_behavior_pb2.FieldBehavior.Value('REQUIRED') in
                 self.options.Extensions[field_behavior_pb2.field_behavior])
 
+    @property
+    def uuid4(self) -> bool:
+        """
+        Return True if the format of this field is a Universally
+        Unique Identifier, version 4 field, False otherwise.
+
+        Returns:
+            bool: Whether this field is UUID4.
+        """
+        return self.options.Extensions[field_info_pb2.field_info].format == field_info_pb2.FieldInfo.Format.Value("UUID4")
+
     @property
     def resource_reference(self) -> Optional[str]:
         """Return a resource reference type if it exists.

tests/unit/schema/wrappers/test_field.py

@@ -17,6 +17,7 @@
 import pytest
 
 from google.api import field_behavior_pb2
+from google.api import field_info_pb2
 from google.api import resource_pb2
 from google.cloud import extended_operations_pb2 as ex_ops_pb2
 from google.protobuf import descriptor_pb2
@@ -140,6 +141,19 @@ def test_not_required():
     assert not field.required
 
 
+def test_uuid4():
+    field = make_field()
+    field.options.Extensions[field_info_pb2.field_info].format = field_info_pb2.FieldInfo.Format.Value(
+        "UUID4"
+    )
+    assert field.uuid4
+
+
+def test_not_uuid4():
+    field = make_field()
+    assert not field.uuid4
+
+
 def test_ident_sphinx():
     field = make_field(type='TYPE_BOOL')
     assert field.ident.sphinx == 'bool'