import sys
import trio

PORT = 8081


async def sender(client_stream):
    print("sender: started!")
    while True:
        data = b"async can sometimes be confusing, but I believe in you!"
        print(f"sender: sending {data!r}")
        await client_stream.send_all(data)
        await trio.sleep(1)


async def receiver(client_stream):
    print("receiver: started!")
    async for data in client_stream:
        print(f"receiver got data {data!r}")
    print("received: connection closed")
    sys.exit()


async def parent():
    print(f"parent: connecting to 127.0.0.1:{PORT}")
    client_stream = await trio.open_tcp_stream("127.0.0.1", PORT)
    async with client_stream:
        async with trio.open_nursery() as nursery:
            print("parent: spawning sender...")
            nursery.start_soon(sender, client_stream)

            print("parent: spawning receiver...")
            # noinspection PyTypeChecker
            nursery.start_soon(receiver, client_stream)

if __name__ == '__main__':
    trio.run(parent)