handle multiple json path query results as ambiguous

nucypher/policy/conditions/offchain.py

@@ -123,20 +123,29 @@ def deserialize_response(self, response: requests.Response) -> Any:
         return data
 
     def query_response(self, data: Any) -> Any:
+
         if not self.query:
             return data  # primitive value
+
         try:
             expression = parse(self.query)
             matches = expression.find(data)
             if not matches:
-                self.logger.info("No matches found for the JSONPath query.")
-                raise ConditionEvaluationFailed(
-                    "No matches found for the JSONPath query."
-                )
-            result = matches[0].value
+                message = f"No matches found for the JSONPath query: {self.query}"
+                self.logger.info(message)
+                raise ConditionEvaluationFailed(message)
         except (JsonPathLexerError, JsonPathParserError) as jsonpath_err:
             self.logger.error(f"JSONPath error occurred: {jsonpath_err}")
             raise ConditionEvaluationFailed(f"JSONPath error: {jsonpath_err}")
+
+        if len(matches) > 1:
+            message = (
+                f"Ambiguous JSONPath query - Multiple matches found for: {self.query}"
+            )
+            self.logger.info(message)
+            raise ConditionEvaluationFailed(message)
+        result = matches[0].value
+
         return result
 
     def verify(self, **context) -> Tuple[bool, Any]:

tests/unit/conditions/test_json_api_condition.py

@@ -202,3 +202,21 @@ def test_json_api_condition_from_lingo_expression():
     lingo_json = json.dumps(lingo_dict)
     condition = JsonApiCondition.from_json(lingo_json)
     assert isinstance(condition, JsonApiCondition)
+
+
+def test_ambiguous_json_path_multiple_results(mocker):
+    mock_response = mocker.Mock(status_code=200)
+    mock_response.json.return_value = {"store": {"book": [{"price": 1}, {"price": 2}]}}
+
+    mocker.patch("requests.get", return_value=mock_response)
+
+    condition = JsonApiCondition(
+        endpoint="https://api.example.com/data",
+        query="$.store.book[*].price",
+        return_value_test=ReturnValueTest("==", 1),
+    )
+
+    with pytest.raises(ConditionEvaluationFailed) as excinfo:
+        condition.verify()
+
+    assert "Ambiguous JSONPath query" in str(excinfo.value)