如何在asyncio中正确调用await函数？

Question

我用 asyncio 创建了一个套接字服务器。从套接字读取是立即完成的，但写入套接字必须根据条件从另一个类调用。我的实现不起作用。请帮忙

class MyAsyncioHandler:
    def __init__(self, reader, writer):
        self.reader = reader
        self.writer = writer
        self._serverThread = _Thread(self)
        self._serverThread.start()
    async def handle_read(self):
        buf = await self.reader.read(8192)
        print(buf)
    async def handle_write(self, data):
        self.writer.write(data)
        await self.writer.drain()
        self.writer.close()

class NewServer:
    def __init__(self, host, port):
        self.host = host
        self.port = port

    async def handle_client(self, reader, writer):
        handler = MyAsyncioHandler(reader, writer)
        await handler.handle_read()
    async def _run(self):
        server = await asyncio.start_server(
            self.handle_client, self.host, self.port
        )
        addr = server.sockets[0].getsockname()
        log(f"Server: Listen {addr}", INFO)
        async with server:
            await server.serve_forever()
    def serve(self):
        asyncio.run(self._run())
class _Thread(Thread):
    def __init__(self, handler):
        Thread.__init__(self)
        self._handler = handler
    def run(self):
        if data:
            loop = asyncio.new_event_loop()
            asyncio.set_event_loop(loop)
            loop.create_task(self._handler.handle_write(data))

server = NewServer('localhost', 5000)
server.serve()
   

Answer 1

你可以尝试：

import asyncio


class MyAsyncioHandler:
    def __call__(self, reader, writer):
        async def _inner():
            await self.handle_read(reader)
            data_to_send = b"Response data"
            await self.handle_write(writer, data_to_send)

        return _inner()

    async def handle_read(self, reader):
        data = await reader.read(8192)
        if data:
            print(f"Received data: {data.decode()}")

    async def handle_write(self, writer, data):
        print("Write", data)
        writer.write(data)
        await writer.drain()
        writer.close()
        await writer.wait_closed()


async def main():
    server = await asyncio.start_server(MyAsyncioHandler(), "127.0.0.1", 5000)
    addr = server.sockets[0].getsockname()
    print(f"Serving on {addr}")
    async with server:
        await server.serve_forever()


if __name__ == "__main__":
    asyncio.run(main())

运行此脚本将在

127.0.0.1:5000

上启动服务器。

在其他终端上，您可以使用以下命令将数据发送到服务器：

$ echo "Hello World" | curl telnet://127.0.0.1:5000