Correctly model JSON repr of complex nested records.

bigquery/google/cloud/bigquery/_helpers.py

@@ -58,10 +58,11 @@ def _record_from_json(value, field):
     """Coerce 'value' to a mapping, if set or not nullable."""
     if _not_null(value, field):
         record = {}
-        for subfield, cell in zip(field.fields, value['f']):
+        record_iter = zip(field.fields, value['f'])
+        for subfield, cell in record_iter:
             converter = _CELLDATA_FROM_JSON[subfield.field_type]
-            if field.mode == 'REPEATED':
-                value = [converter(item, subfield) for item in cell['v']]
+            if subfield.mode == 'REPEATED':
+                value = [converter(item['v'], subfield) for item in cell['v']]
             else:
                 value = converter(cell['v'], subfield)
             record[subfield.name] = value
@@ -103,7 +104,7 @@ def _row_from_json(row, schema):
     for field, cell in zip(schema, row['f']):
         converter = _CELLDATA_FROM_JSON[field.field_type]
         if field.mode == 'REPEATED':
-            row_data.append([converter(item, field)
+            row_data.append([converter(item['v'], field)
                              for item in cell['v']])
         else:
             row_data.append(converter(cell['v'], field))

bigquery/unit_tests/test__helpers.py

@@ -186,7 +186,7 @@ def test_w_scalar_subfield(self):
     def test_w_repeated_subfield(self):
         subfield = _Field('REPEATED', 'color', 'STRING')
         field = _Field('REQUIRED', fields=[subfield])
-        value = {'f': [{'v': ['red', 'yellow', 'blue']}]}
+        value = {'f': [{'v': [{'v': 'red'}, {'v': 'yellow'}, {'v': 'blue'}]}]}
         coerced = self._call_fut(value, field)
         self.assertEqual(coerced, {'color': ['red', 'yellow', 'blue']})
 
@@ -234,6 +234,97 @@ def test_w_string_value(self):
         self.assertEqual(coerced, 'Wonderful!')
 
 
+class Test_row_from_json(unittest.TestCase):
+
+    def _call_fut(self, row, schema):
+        from google.cloud.bigquery._helpers import _row_from_json
+        return _row_from_json(row, schema)
+
+    def test_w_single_scalar_column(self):
+        # SELECT 1 AS col
+        col = _Field('REQUIRED', 'col', 'INTEGER')
+        row = {u'f': [{u'v': u'1'}]}
+        self.assertEqual(self._call_fut(row, schema=[col]), (1,))
+
+    def test_w_single_struct_column(self):
+        # SELECT (1, 2) AS col
+        sub_1 = _Field('REQUIRED', 'sub_1', 'INTEGER')
+        sub_2 = _Field('REQUIRED', 'sub_2', 'INTEGER')
+        col = _Field('REQUIRED', 'col', 'RECORD', fields=[sub_1, sub_2])
+        row = {u'f': [{u'v': {u'f': [{u'v': u'1'}, {u'v': u'2'}]}}]}
+        self.assertEqual(self._call_fut(row, schema=[col]),
+                         ({'sub_1': 1, 'sub_2': 2},))
+
+    def test_w_single_array_column(self):
+        # SELECT [1, 2, 3] as col
+        col = _Field('REPEATED', 'col', 'INTEGER')
+        row = {u'f': [{u'v': [{u'v': u'1'}, {u'v': u'2'}, {u'v': u'3'}]}]}
+        self.assertEqual(self._call_fut(row, schema=[col]),
+                         ([1, 2, 3],))
+
+    def test_w_struct_w_nested_array_column(self):
+        # SELECT ([1, 2], 3, [4, 5]) as col
+        first = _Field('REPEATED', 'first', 'INTEGER')
+        second = _Field('REQUIRED', 'second', 'INTEGER')
+        third = _Field('REPEATED', 'third', 'INTEGER')
+        col = _Field('REQUIRED', 'col', 'RECORD',
+                     fields=[first, second, third])
+        row = {
+            u'f': [
+                {u'v': {
+                    u'f': [
+                        {u'v': [{u'v': u'1'}, {u'v': u'2'}]},
+                        {u'v': u'3'},
+                        {u'v': [{u'v': u'4'}, {u'v': u'5'}]}
+                    ]
+                }},
+            ]
+        }
+        self.assertEqual(
+            self._call_fut(row, schema=[col]),
+            ({u'first': [1, 2], u'second': 3, u'third': [4, 5]},))
+
+    def test_w_array_of_struct(self):
+        # SELECT [(1, 2, 3), (4, 5, 6)] as col
+        first = _Field('REQUIRED', 'first', 'INTEGER')
+        second = _Field('REQUIRED', 'second', 'INTEGER')
+        third = _Field('REQUIRED', 'third', 'INTEGER')
+        col = _Field('REPEATED', 'col', 'RECORD',
+                     fields=[first, second, third])
+        row = {u'f': [{u'v': [
+            {u'v': {u'f': [{u'v': u'1'}, {u'v': u'2'}, {u'v': u'3'}]}},
+            {u'v': {u'f': [{u'v': u'4'}, {u'v': u'5'}, {u'v': u'6'}]}},
+        ]}]}
+        self.assertEqual(
+            self._call_fut(row, schema=[col]),
+            ([
+                {u'first': 1, u'second': 2, u'third': 3},
+                {u'first': 4, u'second': 5, u'third': 6},
+            ],))
+
+    def test_w_array_of_struct_w_array(self):
+        # SELECT [([1, 2, 3], 4), ([5, 6], 7)]
+        first = _Field('REPEATED', 'first', 'INTEGER')
+        second = _Field('REQUIRED', 'second', 'INTEGER')
+        col = _Field('REPEATED', 'col', 'RECORD', fields=[first, second])
+        row = {u'f': [{u'v': [
+            {u'v': {u'f': [
+                {u'v': [{u'v': u'1'}, {u'v': u'2'}, {u'v': u'3'}]},
+                {u'v': u'4'}
+            ]}},
+            {u'v': {u'f': [
+                {u'v': [{u'v': u'5'}, {u'v': u'6'}]},
+                {u'v': u'7'}
+            ]}}
+        ]}]}
+        self.assertEqual(
+            self._call_fut(row, schema=[col]),
+            ([
+                {u'first': [1, 2, 3], u'second': 4},
+                {u'first': [5, 6], u'second': 7},
+            ],))
+
+
 class Test_rows_from_json(unittest.TestCase):
 
     def _call_fut(self, value, field):
@@ -253,12 +344,12 @@ def test_w_record_subfield(self):
             {'f': [
                 {'v': 'Phred Phlyntstone'},
                 {'v': {'f': [{'v': '800'}, {'v': '555-1212'}, {'v': 1}]}},
-                {'v': ['orange', 'black']},
+                {'v': [{'v': 'orange'}, {'v': 'black'}]},
             ]},
             {'f': [
                 {'v': 'Bharney Rhubble'},
                 {'v': {'f': [{'v': '877'}, {'v': '768-5309'}, {'v': 2}]}},
-                {'v': ['brown']},
+                {'v': [{'v': 'brown'}]},
             ]},
             {'f': [
                 {'v': 'Wylma Phlyntstone'},

bigquery/unit_tests/test_table.py

@@ -1173,22 +1173,27 @@ def test_fetch_data_w_repeated_fields(self):
             'pageToken': TOKEN,
             'rows': [
                 {'f': [
-                    {'v': ['red', 'green']},
-                    {'v': [{'f': [{'v': ['1', '2']},
-                                  {'v': ['3.1415', '1.414']}]}]},
+                    {'v': [{'v': 'red'}, {'v': 'green'}]},
+                    {'v': [{
+                        'v': {
+                            'f': [
+                                {'v': [{'v': '1'}, {'v': '2'}]},
+                                {'v': [{'v': '3.1415'}, {'v': '1.414'}]},
+                            ]}
+                    }]},
                 ]},
             ]
         }
         conn = _Connection(DATA)
         client = _Client(project=self.PROJECT, connection=conn)
         dataset = _Dataset(client)
-        full_name = SchemaField('color', 'STRING', mode='REPEATED')
+        color = SchemaField('color', 'STRING', mode='REPEATED')
         index = SchemaField('index', 'INTEGER', 'REPEATED')
         score = SchemaField('score', 'FLOAT', 'REPEATED')
         struct = SchemaField('struct', 'RECORD', mode='REPEATED',
                              fields=[index, score])
         table = self._make_one(self.TABLE_NAME, dataset=dataset,
-                               schema=[full_name, struct])
+                               schema=[color, struct])
 
         iterator = table.fetch_data()
         page = six.next(iterator.pages)

system_tests/bigquery.py

@@ -478,3 +478,49 @@ def _job_done(instance):
         # them here.  The best we can do is not that the API call didn't
         # raise an error, and that the job completed (in the `retry()`
         # above).
+
+    def test_sync_query_w_nested_arrays_and_structs(self):
+        EXAMPLES = [
+            {
+                'sql': 'SELECT 1',
+                'expected': 1,
+            },
+            {
+                'sql': 'SELECT (1, 2)',
+                'expected': {'_field_1': 1, '_field_2': 2},
+            },
+            {
+                'sql': 'SELECT [1, 2, 3]',
+                'expected': [1, 2, 3],
+            },
+            {
+                'sql': 'SELECT ([1, 2], 3, [4, 5])',
+                'expected':
+                    {'_field_1': [1, 2], '_field_2': 3, '_field_3': [4, 5]},
+            },
+            {
+                'sql': 'SELECT [(1, 2, 3), (4, 5, 6)]',
+                'expected': [
+                    {'_field_1': 1, '_field_2': 2, '_field_3': 3},
+                    {'_field_1': 4, '_field_2': 5, '_field_3': 6},
+                ],
+            },
+            {
+                'sql': 'SELECT [([1, 2, 3], 4), ([5, 6], 7)]',
+                'expected': [
+                    {u'_field_1': [1, 2, 3], u'_field_2': 4},
+                    {u'_field_1': [5, 6], u'_field_2': 7},
+                ],
+            },
+            {
+                'sql': 'SELECT ARRAY(SELECT STRUCT([1, 2]))',
+                'expected': [{u'_field_1': [1, 2]}],
+            },
+        ]
+        for example in EXAMPLES:
+            query = Config.CLIENT.run_sync_query(example['sql'])
+            query.use_legacy_sql = False
+            query.run()
+            self.assertEqual(len(query.rows), 1)
+            self.assertEqual(len(query.rows[0]), 1)
+            self.assertEqual(query.rows[0][0], example['expected'])