Validate APIResponse JSON payload key types

Co-authored-by: Shri Sukhani <shrisukhani@users.noreply.github.com>

Author: cursoragent

hyperbrowser/transport/base.py

@@ -28,6 +28,14 @@ def from_json(
                 f"Failed to parse response data for {model_name}: "
                 f"expected a mapping but received {actual_type_name}"
             )
+        for key in json_data.keys():
+            if isinstance(key, str):
+                continue
+            key_type_name = type(key).__name__
+            raise HyperbrowserError(
+                f"Failed to parse response data for {model_name}: "
+                f"expected string keys but received {key_type_name}"
+            )
         try:
             return cls(data=model(**json_data))
         except HyperbrowserError:

tests/test_transport_base.py

@@ -43,6 +43,20 @@ def test_api_response_from_json_rejects_non_mapping_inputs() -> None:
         )
 
 
+def test_api_response_from_json_rejects_non_string_mapping_keys() -> None:
+    with pytest.raises(
+        HyperbrowserError,
+        match=(
+            "Failed to parse response data for _SampleResponseModel: "
+            "expected string keys but received int"
+        ),
+    ):
+        APIResponse.from_json(
+            cast("dict[str, object]", {1: "job-1"}),
+            _SampleResponseModel,
+        )
+
+
 def test_api_response_from_json_wraps_non_hyperbrowser_errors() -> None:
     with pytest.raises(
         HyperbrowserError,