fix: Handle non-json-serializable values in the execute_sql tool

This change takes cares of SQL results containing values that are not json serializable (e.g. datetime, bignumeric) by converting them to their string representation.

PiperOrigin-RevId: 785719997

src/google/adk/tools/bigquery/metadata_tool.py

@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from __future__ import annotations
+
 from google.auth.credentials import Credentials
 from google.cloud import bigquery
 

src/google/adk/tools/bigquery/query_tool.py

@@ -12,7 +12,10 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from __future__ import annotations
+
 import functools
+import json
 import types
 from typing import Callable
 
@@ -159,7 +162,18 @@ def execute_sql(
         project=project_id,
         max_results=MAX_DOWNLOADED_QUERY_RESULT_ROWS,
     )
-    rows = [{key: val for key, val in row.items()} for row in row_iterator]
+    rows = []
+    for row in row_iterator:
+      row_values = {}
+      for key, val in row.items():
+        try:
+          # if the json serialization of the value succeeds, use it as is
+          json.dumps(val)
+        except:
+          val = str(val)
+        row_values[key] = val
+      rows.append(row_values)
+
     result = {"status": "SUCCESS", "rows": rows}
     if (
         MAX_DOWNLOADED_QUERY_RESULT_ROWS is not None

tests/unittests/tools/bigquery/test_bigquery_query_tool.py

@@ -14,11 +14,15 @@
 
 from __future__ import annotations
 
+import datetime
+import decimal
 import os
 import textwrap
 from typing import Optional
 from unittest import mock
 
+import dateutil
+import dateutil.relativedelta
 from google.adk.tools import BaseTool
 from google.adk.tools.bigquery import BigQueryCredentialsConfig
 from google.adk.tools.bigquery import BigQueryToolset
@@ -829,3 +833,143 @@ def test_execute_sql_no_default_auth(
   result = execute_sql(project, query, credentials, tool_config, tool_context)
   assert result == {"status": "SUCCESS", "rows": query_result}
   mock_default_auth.assert_not_called()
+
+
+@pytest.mark.parametrize(
+    ("query", "query_result", "tool_result_rows"),
+    [
+        pytest.param(
+            "SELECT [1,2,3] AS x",
+            [{"x": [1, 2, 3]}],
+            [{"x": [1, 2, 3]}],
+            id="ARRAY",
+        ),
+        pytest.param(
+            "SELECT TRUE AS x", [{"x": True}], [{"x": True}], id="BOOL"
+        ),
+        pytest.param(
+            "SELECT b'Hello World!' AS x",
+            [{"x": b"Hello World!"}],
+            [{"x": "b'Hello World!'"}],
+            id="BYTES",
+        ),
+        pytest.param(
+            "SELECT DATE '2025-07-21' AS x",
+            [{"x": datetime.date(2025, 7, 21)}],
+            [{"x": "2025-07-21"}],
+            id="DATE",
+        ),
+        pytest.param(
+            "SELECT DATETIME '2025-07-21 14:30:45' AS x",
+            [{"x": datetime.datetime(2025, 7, 21, 14, 30, 45)}],
+            [{"x": "2025-07-21 14:30:45"}],
+            id="DATETIME",
+        ),
+        pytest.param(
+            "SELECT ST_GEOGFROMTEXT('POINT(-122.21 47.48)') as x",
+            [{"x": "POINT(-122.21 47.48)"}],
+            [{"x": "POINT(-122.21 47.48)"}],
+            id="GEOGRAPHY",
+        ),
+        pytest.param(
+            "SELECT INTERVAL 10 DAY as x",
+            [{"x": dateutil.relativedelta.relativedelta(days=10)}],
+            [{"x": "relativedelta(days=+10)"}],
+            id="INTERVAL",
+        ),
+        pytest.param(
+            "SELECT JSON_OBJECT('name', 'Alice', 'age', 30) AS x",
+            [{"x": {"age": 30, "name": "Alice"}}],
+            [{"x": {"age": 30, "name": "Alice"}}],
+            id="JSON",
+        ),
+        pytest.param("SELECT 1 AS x", [{"x": 1}], [{"x": 1}], id="INT64"),
+        pytest.param(
+            "SELECT CAST(1.2 AS NUMERIC) AS x",
+            [{"x": decimal.Decimal("1.2")}],
+            [{"x": "1.2"}],
+            id="NUMERIC",
+        ),
+        pytest.param(
+            "SELECT CAST(1.2 AS BIGNUMERIC) AS x",
+            [{"x": decimal.Decimal("1.2")}],
+            [{"x": "1.2"}],
+            id="BIGNUMERIC",
+        ),
+        pytest.param(
+            "SELECT 1.23 AS x", [{"x": 1.23}], [{"x": 1.23}], id="FLOAT64"
+        ),
+        pytest.param(
+            "SELECT RANGE(DATE '2023-01-01', DATE '2023-01-31') as x",
+            [{
+                "x": {
+                    "start": datetime.date(2023, 1, 1),
+                    "end": datetime.date(2023, 1, 31),
+                }
+            }],
+            [{
+                "x": (
+                    "{'start': datetime.date(2023, 1, 1), 'end':"
+                    " datetime.date(2023, 1, 31)}"
+                )
+            }],
+            id="RANGE",
+        ),
+        pytest.param(
+            "SELECT 'abc' AS x", [{"x": "abc"}], [{"x": "abc"}], id="STRING"
+        ),
+        pytest.param(
+            "SELECT STRUCT('Alice' AS name, 30 AS age) as x",
+            [{"x": {"name": "Alice", "age": 30}}],
+            [{"x": {"name": "Alice", "age": 30}}],
+            id="STRUCT",
+        ),
+        pytest.param(
+            "SELECT TIME '10:30:45' as x",
+            [{"x": datetime.time(10, 30, 45)}],
+            [{"x": "10:30:45"}],
+            id="TIME",
+        ),
+        pytest.param(
+            "SELECT TIMESTAMP '2025-07-21 10:30:45-07:00' as x",
+            [{
+                "x": datetime.datetime(
+                    2025, 7, 21, 17, 30, 45, tzinfo=datetime.timezone.utc
+                )
+            }],
+            [{"x": "2025-07-21 17:30:45+00:00"}],
+            id="TIMESTAMP",
+        ),
+        pytest.param(
+            "SELECT NULL AS x", [{"x": None}], [{"x": None}], id="NULL"
+        ),
+    ],
+)
+@mock.patch.dict(os.environ, {}, clear=True)
+@mock.patch("google.cloud.bigquery.Client.query_and_wait", autospec=True)
+@mock.patch("google.cloud.bigquery.Client.query", autospec=True)
+def test_execute_sql_result_dtype(
+    mock_query, mock_query_and_wait, query, query_result, tool_result_rows
+):
+  """Test execute_sql tool invocation for various BigQuery data types.
+
+  See all the supported BigQuery data types at
+  https://cloud.google.com/bigquery/docs/reference/standard-sql/data-types#data_type_list.
+  """
+  project = "my_project"
+  statement_type = "SELECT"
+  credentials = mock.create_autospec(Credentials, instance=True)
+  tool_config = BigQueryToolConfig()
+  tool_context = mock.create_autospec(ToolContext, instance=True)
+
+  # Simulate the result of query API
+  query_job = mock.create_autospec(bigquery.QueryJob)
+  query_job.statement_type = statement_type
+  mock_query.return_value = query_job
+
+  # Simulate the result of query_and_wait API
+  mock_query_and_wait.return_value = query_result
+
+  # Test the tool worked without invoking default auth
+  result = execute_sql(project, query, credentials, tool_config, tool_context)
+  assert result == {"status": "SUCCESS", "rows": tool_result_rows}