def test_extraction_with_database_specified(self):
        # type: () -> None
        with patch.object(SQLAlchemyExtractor,
                          '_get_connection') as mock_connection:
            connection = MagicMock()
            mock_connection.return_value = connection
            sql_execute = MagicMock()
            connection.execute = sql_execute

            sql_execute.return_value = [{
                'schema': 'test_schema',
                'name': 'test_table',
                'description': 'a table for testing',
                'cluster': 'MY_CLUSTER',
                'is_view': 'false',
                'col_name': 'ds',
                'col_type': 'varchar',
                'col_description': None,
                'col_sort_order': 0
            }]

            extractor = SnowflakeMetadataExtractor()
            extractor.init(self.conf)
            actual = extractor.extract()
            expected = TableMetadata(
                self.database_key, 'MY_CLUSTER', 'test_schema', 'test_table',
                'a table for testing',
                [ColumnMetadata('ds', None, 'varchar', 0)])

            self.assertEqual(expected.__repr__(), actual.__repr__())
            self.assertIsNone(extractor.extract())
    def test_extraction_with_empty_query_result(self) -> None:
        """
        Test Extraction with empty result from query
        """
        with patch.object(SQLAlchemyExtractor, '_get_connection'):
            extractor = SnowflakeMetadataExtractor()
            extractor.init(self.conf)

            results = extractor.extract()
            self.assertEqual(results, None)
    def test_extraction_with_single_result(self):
        # type: () -> None
        with patch.object(SQLAlchemyExtractor,
                          '_get_connection') as mock_connection:
            connection = MagicMock()
            mock_connection.return_value = connection
            sql_execute = MagicMock()
            connection.execute = sql_execute
            table = {
                'schema':
                'test_schema',
                'name':
                'test_table',
                'description':
                'a table for testing',
                'cluster':
                self.conf['extractor.snowflake_metadata.{}'.format(
                    SnowflakeMetadataExtractor.CLUSTER_KEY)],
                'is_view':
                'false'
            }

            sql_execute.return_value = [
                self._union(
                    {
                        'col_name': 'col_id1',
                        'col_type': 'number',
                        'col_description': 'description of id1',
                        'col_sort_order': 0
                    }, table),
                self._union(
                    {
                        'col_name': 'col_id2',
                        'col_type': 'number',
                        'col_description': 'description of id2',
                        'col_sort_order': 1
                    }, table),
                self._union(
                    {
                        'col_name': 'is_active',
                        'col_type': 'boolean',
                        'col_description': None,
                        'col_sort_order': 2
                    }, table),
                self._union(
                    {
                        'col_name': 'source',
                        'col_type': 'varchar',
                        'col_description': 'description of source',
                        'col_sort_order': 3
                    }, table),
                self._union(
                    {
                        'col_name': 'etl_created_at',
                        'col_type': 'timestamp_ltz',
                        'col_description': 'description of etl_created_at',
                        'col_sort_order': 4
                    }, table),
                self._union(
                    {
                        'col_name': 'ds',
                        'col_type': 'varchar',
                        'col_description': None,
                        'col_sort_order': 5
                    }, table)
            ]

            extractor = SnowflakeMetadataExtractor()
            extractor.init(self.conf)
            actual = extractor.extract()
            expected = TableMetadata(
                'snowflake', 'MY_CLUSTER', 'test_schema', 'test_table',
                'a table for testing', [
                    ColumnMetadata('col_id1', 'description of id1', 'number',
                                   0),
                    ColumnMetadata('col_id2', 'description of id2', 'number',
                                   1),
                    ColumnMetadata('is_active', None, 'boolean', 2),
                    ColumnMetadata('source', 'description of source',
                                   'varchar', 3),
                    ColumnMetadata('etl_created_at',
                                   'description of etl_created_at',
                                   'timestamp_ltz', 4),
                    ColumnMetadata('ds', None, 'varchar', 5)
                ])

            self.assertEqual(expected.__repr__(), actual.__repr__())
            self.assertIsNone(extractor.extract())
    def test_extraction_with_multiple_result(self) -> None:
        with patch.object(SQLAlchemyExtractor,
                          '_get_connection') as mock_connection:
            connection = MagicMock()
            mock_connection.return_value = connection
            sql_execute = MagicMock()
            connection.execute = sql_execute
            table = {
                'schema':
                'test_schema1',
                'name':
                'test_table1',
                'description':
                'test table 1',
                'cluster':
                self.conf[
                    f'extractor.snowflake_metadata.{SnowflakeMetadataExtractor.CLUSTER_KEY}'],
                'is_view':
                'nottrue'
            }

            table1 = {
                'schema':
                'test_schema1',
                'name':
                'test_table2',
                'description':
                'test table 2',
                'cluster':
                self.conf[
                    f'extractor.snowflake_metadata.{SnowflakeMetadataExtractor.CLUSTER_KEY}'],
                'is_view':
                'false'
            }

            table2 = {
                'schema':
                'test_schema2',
                'name':
                'test_table3',
                'description':
                'test table 3',
                'cluster':
                self.conf[
                    f'extractor.snowflake_metadata.{SnowflakeMetadataExtractor.CLUSTER_KEY}'],
                'is_view':
                'true'
            }

            sql_execute.return_value = [
                self._union(
                    {
                        'col_name': 'col_id1',
                        'col_type': 'number',
                        'col_description': 'description of col_id1',
                        'col_sort_order': 0
                    }, table),
                self._union(
                    {
                        'col_name': 'col_id2',
                        'col_type': 'number',
                        'col_description': 'description of col_id2',
                        'col_sort_order': 1
                    }, table),
                self._union(
                    {
                        'col_name': 'is_active',
                        'col_type': 'boolean',
                        'col_description': None,
                        'col_sort_order': 2
                    }, table),
                self._union(
                    {
                        'col_name': 'source',
                        'col_type': 'varchar',
                        'col_description': 'description of source',
                        'col_sort_order': 3
                    }, table),
                self._union(
                    {
                        'col_name': 'etl_created_at',
                        'col_type': 'timestamp_ltz',
                        'col_description': 'description of etl_created_at',
                        'col_sort_order': 4
                    }, table),
                self._union(
                    {
                        'col_name': 'ds',
                        'col_type': 'varchar',
                        'col_description': None,
                        'col_sort_order': 5
                    }, table),
                self._union(
                    {
                        'col_name': 'col_name',
                        'col_type': 'varchar',
                        'col_description': 'description of col_name',
                        'col_sort_order': 0
                    }, table1),
                self._union(
                    {
                        'col_name': 'col_name2',
                        'col_type': 'varchar',
                        'col_description': 'description of col_name2',
                        'col_sort_order': 1
                    }, table1),
                self._union(
                    {
                        'col_name': 'col_id3',
                        'col_type': 'varchar',
                        'col_description': 'description of col_id3',
                        'col_sort_order': 0
                    }, table2),
                self._union(
                    {
                        'col_name': 'col_name3',
                        'col_type': 'varchar',
                        'col_description': 'description of col_name3',
                        'col_sort_order': 1
                    }, table2)
            ]

            extractor = SnowflakeMetadataExtractor()
            extractor.init(self.conf)

            expected = TableMetadata(
                'snowflake', self.conf[
                    f'extractor.snowflake_metadata.{SnowflakeMetadataExtractor.CLUSTER_KEY}'],
                'test_schema1', 'test_table1', 'test table 1', [
                    ColumnMetadata('col_id1', 'description of col_id1',
                                   'number', 0),
                    ColumnMetadata('col_id2', 'description of col_id2',
                                   'number', 1),
                    ColumnMetadata('is_active', None, 'boolean', 2),
                    ColumnMetadata('source', 'description of source',
                                   'varchar', 3),
                    ColumnMetadata('etl_created_at',
                                   'description of etl_created_at',
                                   'timestamp_ltz', 4),
                    ColumnMetadata('ds', None, 'varchar', 5)
                ])
            self.assertEqual(expected.__repr__(),
                             extractor.extract().__repr__())

            expected = TableMetadata(
                'snowflake', self.conf[
                    f'extractor.snowflake_metadata.{SnowflakeMetadataExtractor.CLUSTER_KEY}'],
                'test_schema1', 'test_table2', 'test table 2', [
                    ColumnMetadata('col_name', 'description of col_name',
                                   'varchar', 0),
                    ColumnMetadata('col_name2', 'description of col_name2',
                                   'varchar', 1)
                ])
            self.assertEqual(expected.__repr__(),
                             extractor.extract().__repr__())

            expected = TableMetadata(
                'snowflake', self.conf[
                    f'extractor.snowflake_metadata.{SnowflakeMetadataExtractor.CLUSTER_KEY}'],
                'test_schema2', 'test_table3', 'test table 3', [
                    ColumnMetadata('col_id3', 'description of col_id3',
                                   'varchar', 0),
                    ColumnMetadata('col_name3', 'description of col_name3',
                                   'varchar', 1)
                ], True)
            self.assertEqual(expected.__repr__(),
                             extractor.extract().__repr__())

            self.assertIsNone(extractor.extract())
            self.assertIsNone(extractor.extract())