support map type

[kapilt]

interesting project, one thought would be to add support for a custom type for maps https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ql-reference.data-types.html

[passren]

@kapilt Thanks for your idea. It indeed support all data types listed in the AWS doc, including map (even the nested map). Please refer to the sample here PyDynamoDB is able to pass python built-in-type data to a qmark parameter in Partiql and convert the response to built-in type data.

Insert map data into ddb:

        sql_one_row_2_1_ = (
            """
            INSERT INTO %s VALUE {
                'key_partition': ?, 'key_sort': ?, 'col_nested_list': ?, 'col_nested_map': ?
            }
        """
            % TESTCASE01_TABLE
        )
        params_2_1_ = [
            "test_one_row_2",
            1,
            [
                "Hello",
                "World",
                1.0,
                b"1",
                {1, 2, 3},
                {"1", "2", "3"},
                {"name": "test case 3", "version": 1.0},
            ],
            {
                "name": "test case 3",
                "version": 1.0,
                "list": ["Hello", "World", {1, 2, 3}, {"1", "2"}, 2],
                "map": {"str": "Best", "num": 1, "chinese": u"你好"},
            },
        ]
        cursor.execute(sql_one_row_2_1_, params_2_1_)

Get map data from DDB:

        cursor.execute(
            """
            SELECT col_nested_list, col_nested_map FROM %s
            WHERE key_partition = ?
            AND key_sort = ?
        """
            % TESTCASE01_TABLE,
            ["test_one_row_2", 1],
        )
        row = cursor.fetchone()
        desc = cursor.description
        assert self._get_value_by_column_name(desc, row, "col_nested_list") == [
                                                    "Hello", "World", 1.0,
                                                    b"1", {1, 2, 3}, {"1", "2", "3"},
                                                    {"name": "test case 3", "version": 1.0},
                                                ]
        assert self._get_value_by_column_name(desc, row, "col_nested_map") == {
                                                    "name": "test case 3",
                                                    "version": 1.0,
                                                    "list": ["Hello", "World", {1, 2, 3}, {"1", "2"}, 2],
                                                    "map": {"str": "Best", "num": 1, "chinese": u"你好"},
                                                }

[kapilt]

Thanks for the pointer!

[kapilt]

that's helpful on dbapi, I think the context I meant was a custom type for sqlalchemy to take advantage of key/value retrieval and set.