py-libp2p/examples/chat/chat.py

104 lines
3.4 KiB
Python
Executable File

import argparse
import sys
import multiaddr
import trio
from libp2p import new_host
from libp2p.network.stream.net_stream_interface import INetStream
from libp2p.peer.peerinfo import info_from_p2p_addr
from libp2p.typing import TProtocol
PROTOCOL_ID = TProtocol("/chat/1.0.0")
MAX_READ_LEN = 2 ** 32 - 1
async def read_data(stream: INetStream) -> None:
while True:
read_bytes = await stream.read(MAX_READ_LEN)
if read_bytes is not None:
read_string = read_bytes.decode()
if read_string != "\n":
# Green console colour: \x1b[32m
# Reset console colour: \x1b[0m
print("\x1b[32m %s\x1b[0m " % read_string, end="")
async def write_data(stream: INetStream) -> None:
async_f = trio.wrap_file(sys.stdin)
while True:
line = await async_f.readline()
await stream.write(line.encode())
async def run(port: int, destination: str) -> None:
localhost_ip = "127.0.0.1"
listen_addr = multiaddr.Multiaddr(f"/ip4/0.0.0.0/tcp/{port}")
host = new_host()
async with host.run(listen_addrs=[listen_addr]), trio.open_nursery() as nursery:
if not destination: # its the server
async def stream_handler(stream: INetStream) -> None:
nursery.start_soon(read_data, stream)
nursery.start_soon(write_data, stream)
host.set_stream_handler(PROTOCOL_ID, stream_handler)
print(
f"Run 'python ./examples/chat/chat.py "
f"-p {int(port) + 1} "
f"-d /ip4/{localhost_ip}/tcp/{port}/p2p/{host.get_id().pretty()}' "
"on another console."
)
print("Waiting for incoming connection...")
else: # its the client
maddr = multiaddr.Multiaddr(destination)
info = info_from_p2p_addr(maddr)
# Associate the peer with local ip address
await host.connect(info)
# Start a stream with the destination.
# Multiaddress of the destination peer is fetched from the peerstore using 'peerId'.
stream = await host.new_stream(info.peer_id, [PROTOCOL_ID])
nursery.start_soon(read_data, stream)
nursery.start_soon(write_data, stream)
print(f"Connected to peer {info.addrs[0]}")
await trio.sleep_forever()
def main() -> None:
description = """
This program demonstrates a simple p2p chat application using libp2p.
To use it, first run 'python ./chat -p <PORT>', where <PORT> is the port number.
Then, run another host with 'python ./chat -p <ANOTHER_PORT> -d <DESTINATION>',
where <DESTINATION> is the multiaddress of the previous listener host.
"""
example_maddr = (
"/ip4/127.0.0.1/tcp/8000/p2p/QmQn4SwGkDZKkUEpBRBvTmheQycxAHJUNmVEnjA2v1qe8Q"
)
parser = argparse.ArgumentParser(description=description)
parser.add_argument(
"-p", "--port", default=8000, type=int, help="source port number"
)
parser.add_argument(
"-d",
"--destination",
type=str,
help=f"destination multiaddr string, e.g. {example_maddr}",
)
args = parser.parse_args()
if not args.port:
raise RuntimeError("was not able to determine a local port")
try:
trio.run(run, *(args.port, args.destination))
except KeyboardInterrupt:
pass
if __name__ == "__main__":
main()