py-libp2p/libp2p/transport/tcp/tcp.py
2019-10-24 20:10:45 +02:00

92 lines
3.0 KiB
Python

import asyncio
from socket import socket
from typing import List
from multiaddr import Multiaddr
from libp2p.network.connection.raw_connection import RawConnection
from libp2p.network.connection.raw_connection_interface import IRawConnection
from libp2p.transport.exceptions import OpenConnectionError
from libp2p.transport.listener_interface import IListener
from libp2p.transport.transport_interface import ITransport
from libp2p.transport.typing import THandler
class TCPListener(IListener):
multiaddrs: List[Multiaddr]
server = None
def __init__(self, handler_function: THandler) -> None:
self.multiaddrs = []
self.server = None
self.handler = handler_function
async def listen(self, maddr: Multiaddr) -> bool:
"""
put listener in listening mode and wait for incoming connections.
:param maddr: maddr of peer
:return: return True if successful
"""
self.server = await asyncio.start_server(
self.handler,
maddr.value_for_protocol("ip4"),
maddr.value_for_protocol("tcp"),
)
socket = self.server.sockets[0]
self.multiaddrs.append(_multiaddr_from_socket(socket))
return True
def get_addrs(self) -> List[Multiaddr]:
"""
retrieve list of addresses the listener is listening on.
:return: return list of addrs
"""
# TODO check if server is listening
return self.multiaddrs
async def close(self) -> None:
"""close the listener such that no more connections can be open on this
transport instance."""
if self.server is None:
return
self.server.close()
await self.server.wait_closed()
self.server = None
class TCP(ITransport):
async def dial(self, maddr: Multiaddr) -> IRawConnection:
"""
dial a transport to peer listening on multiaddr.
:param maddr: multiaddr of peer
:return: `RawConnection` if successful
:raise OpenConnectionError: raised when failed to open connection
"""
self.host = maddr.value_for_protocol("ip4")
self.port = int(maddr.value_for_protocol("tcp"))
try:
reader, writer = await asyncio.open_connection(self.host, self.port)
except (ConnectionAbortedError, ConnectionRefusedError) as error:
raise OpenConnectionError(error)
return RawConnection(reader, writer, True)
def create_listener(self, handler_function: THandler) -> TCPListener:
"""
create listener on transport.
:param handler_function: a function called when a new connection is received
that takes a connection as argument which implements interface-connection
:return: a listener object that implements listener_interface.py
"""
return TCPListener(handler_function)
def _multiaddr_from_socket(socket: socket) -> Multiaddr:
return Multiaddr("/ip4/%s/tcp/%s" % socket.getsockname())