py-libp2p/libp2p/protocol_muxer/multiselect_client_interface.py
2019-10-24 20:10:45 +02:00

48 lines
1.6 KiB
Python

from abc import ABC, abstractmethod
from typing import Sequence
from libp2p.protocol_muxer.multiselect_communicator_interface import (
IMultiselectCommunicator,
)
from libp2p.typing import TProtocol
class IMultiselectClient(ABC):
"""Client for communicating with receiver's multiselect module in order to
select a protocol id to communicate over."""
async def handshake(self, communicator: IMultiselectCommunicator) -> None:
"""
Ensure that the client and multiselect are both using the same
multiselect protocol.
:param stream: stream to communicate with multiselect over
:raise Exception: multiselect protocol ID mismatch
"""
@abstractmethod
async def select_one_of(
self, protocols: Sequence[TProtocol], communicator: IMultiselectCommunicator
) -> TProtocol:
"""
For each protocol, send message to multiselect selecting protocol and
fail if multiselect does not return same protocol. Returns first
protocol that multiselect agrees on (i.e. that multiselect selects)
:param protocol: protocol to select
:param stream: stream to communicate with multiselect over
:return: selected protocol
"""
async def try_select(
self, communicator: IMultiselectCommunicator, protocol: TProtocol
) -> TProtocol:
"""
Try to select the given protocol or raise exception if fails.
:param communicator: communicator to use to communicate with counterparty
:param protocol: protocol to select
:raise Exception: error in protocol selection
:return: selected protocol
"""