py-libp2p/libp2p/protocol_muxer/multiselect_communicator.py
2019-09-19 22:19:36 +08:00

40 lines
1.4 KiB
Python

from libp2p.exceptions import ParseError
from libp2p.io.abc import ReadWriteCloser
from libp2p.io.exceptions import IOException
from libp2p.utils import encode_delim, read_delim
from .exceptions import MultiselectCommunicatorError
from .multiselect_communicator_interface import IMultiselectCommunicator
class MultiselectCommunicator(IMultiselectCommunicator):
read_writer: ReadWriteCloser
def __init__(self, read_writer: ReadWriteCloser) -> None:
self.read_writer = read_writer
async def write(self, msg_str: str) -> None:
"""
:raise MultiselectCommunicatorError: raised when failed to write to underlying reader
"""
msg_bytes = encode_delim(msg_str.encode())
try:
await self.read_writer.write(msg_bytes)
except IOException:
raise MultiselectCommunicatorError(
"fail to write to multiselect communicator"
)
async def read(self) -> str:
"""
:raise MultiselectCommunicatorError: raised when failed to read from underlying reader
"""
try:
data = await read_delim(self.read_writer)
# `IOException` includes `IncompleteReadError` and `StreamError`
except (ParseError, IOException, ValueError):
raise MultiselectCommunicatorError(
"fail to read from multiselect communicator"
)
return data.decode()