feat: support JSON type in insert_rows and as a scalar query parameter (#1757)

Co-authored-by: Kira <kirnendra@google.com>

Author: tswast

google/cloud/bigquery/_helpers.py

@@ -374,6 +374,13 @@ def _bytes_to_json(value):
  return value
 
 
+def _json_to_json(value):
+ """Coerce 'value' to a BigQuery REST API representation."""
+ if value is None:
+ return None
+ return json.dumps(value)
+
+
 def _timestamp_to_json_parameter(value):
  """Coerce 'value' to an JSON-compatible representation.
 
@@ -439,7 +446,7 @@ def _time_to_json(value):
  "DATETIME": _datetime_to_json,
  "DATE": _date_to_json,
  "TIME": _time_to_json,
- "JSON": _json_from_json,
+ "JSON": _json_to_json,
  # Make sure DECIMAL and BIGDECIMAL are handled, even though
  # requests for them should be converted to NUMERIC. Better safe
  # than sorry.

tests/system/test_client.py

@@ -2049,13 +2049,18 @@ def test_insert_rows_nested_nested(self):
  ),
  ],
  ),
+ SF("json_col", "JSON"),
  ]
  record = {
  "nested_string": "another string value",
  "nested_repeated": [0, 1, 2],
  "nested_record": {"nested_nested_string": "some deep insight"},
  }
- to_insert = [("Some value", record)]
+ json_record = {
+ "json_array": [1, 2, 3],
+ "json_object": {"alpha": "abc", "num": 123},
+ }
+ to_insert = [("Some value", record, json_record)]
  table_id = "test_table"
  dataset = self.temp_dataset(_make_dataset_id("issue_2951"))
  table_arg = Table(dataset.table(table_id), schema=schema)

tests/system/test_query.py

@@ -256,6 +256,18 @@ def test_query_statistics(bigquery_client, query_api_method):
  )
  ],
  ),
+ pytest.param(
+ "SELECT @json",
+ {"alpha": "abc", "num": [1, 2, 3]},
+ [
+ ScalarQueryParameter(
+ name="json",
+ type_="JSON",
+ value={"alpha": "abc", "num": [1, 2, 3]},
+ )
+ ],
+ id="scalar-json",
+ ),
  (
  "SELECT @naive_time",
  datetime.time(12, 41, 9, 62500),

tests/unit/test__helpers.py

@@ -886,6 +886,16 @@ def test_w_known_field_type(self):
  converted = self._call_fut(field, original)
  self.assertEqual(converted, str(original))
 
+ def test_w_scalar_none(self):
+ import google.cloud.bigquery._helpers as module_under_test
+
+ scalar_types = module_under_test._SCALAR_VALUE_TO_JSON_ROW.keys()
+ for type_ in scalar_types:
+ field = _make_field(type_)
+ original = None
+ converted = self._call_fut(field, original)
+ self.assertIsNone(converted, msg=f"{type_} did not return None")
+
 
 class Test_single_field_to_json(unittest.TestCase):
  def _call_fut(self, field, value):
@@ -921,6 +931,12 @@ def test_w_scalar_ignores_mode(self):
  converted = self._call_fut(field, original)
  self.assertEqual(converted, original)
 
+ def test_w_scalar_json(self):
+ field = _make_field("JSON")
+ original = {"alpha": "abc", "num": [1, 2, 3]}
+ converted = self._call_fut(field, original)
+ self.assertEqual(converted, json.dumps(original))
+
 
 class Test_repeated_field_to_json(unittest.TestCase):
  def _call_fut(self, field, value):