test_connection.py 文件源码

def test_use_requested_compression(self, *args):
        c = self.make_connection()
        c._requests = {0: (c._handle_options_response, ProtocolHandler.decode_message, [])}
        c.defunct = Mock()
        # request snappy compression
        c.compression = "snappy"

        locally_supported_compressions.pop('lz4', None)
        locally_supported_compressions.pop('snappy', None)
        locally_supported_compressions['lz4'] = ('lz4compress', 'lz4decompress')
        locally_supported_compressions['snappy'] = ('snappycompress', 'snappydecompress')

        # read in a SupportedMessage response
        header = self.make_header_prefix(SupportedMessage)

        # the server only supports snappy
        options_buf = BytesIO()
        write_stringmultimap(options_buf, {
            'CQL_VERSION': ['3.0.3'],
            'COMPRESSION': ['snappy', 'lz4']
        })
        options = options_buf.getvalue()

        c.process_msg(_Frame(version=4, flags=0, stream=0, opcode=SupportedMessage.opcode, body_offset=9, end_pos=9 + len(options)), options)

        self.assertEqual(c.decompressor, locally_supported_compressions['snappy'][1])