def _execute_transaction()

in redis/client.py [0:0]
48 lines of code
22 McCabe index (conditional complexity)

    def _execute_transaction(self, connection, commands, raise_on_error) -> List:
        cmds = chain([(("MULTI",), {})], commands, [(("EXEC",), {})])
        all_cmds = connection.pack_commands(
            [args for args, options in cmds if EMPTY_RESPONSE not in options]
        )
        connection.send_packed_command(all_cmds)
        errors = []

        # parse off the response for MULTI
        # NOTE: we need to handle ResponseErrors here and continue
        # so that we read all the additional command messages from
        # the socket
        try:
            self.parse_response(connection, "_")
        except ResponseError as e:
            errors.append((0, e))

        # and all the other commands
        for i, command in enumerate(commands):
            if EMPTY_RESPONSE in command[1]:
                errors.append((i, command[1][EMPTY_RESPONSE]))
            else:
                try:
                    self.parse_response(connection, "_")
                except ResponseError as e:
                    self.annotate_exception(e, i + 1, command[0])
                    errors.append((i, e))

        # parse the EXEC.
        try:
            response = self.parse_response(connection, "_")
        except ExecAbortError:
            if errors:
                raise errors[0][1]
            raise

        # EXEC clears any watched keys
        self.watching = False

        if response is None:
            raise WatchError("Watched variable changed.")

        # put any parse errors into the response
        for i, e in errors:
            response.insert(i, e)

        if len(response) != len(commands):
            self.connection.disconnect()
            raise ResponseError(
                "Wrong number of response items from pipeline execution"
            )

        # find any errors in the response and raise if necessary
        if raise_on_error:
            self.raise_first_error(commands, response)

        # We have to run response callbacks manually
        data = []
        for r, cmd in zip(response, commands):
            if not isinstance(r, Exception):
                args, options = cmd
                # Remove keys entry, it needs only for cache.
                options.pop("keys", None)
                command_name = args[0]
                if command_name in self.response_callbacks:
                    r = self.response_callbacks[command_name](r, **options)
            data.append(r)
        return data