【Python】非阻塞IO

#  特点:不断对服务进行询问,以实现非IO阻塞模型
#  缺点: 1.不断询问导致CPU占用高
#        2.询问的间隔时间中,客户端发送的请求无法响应
#  不推荐使用!


from socket import *


class Server(object):
    def __init__(self, ip_bind=('127.0.0.1', 8080)):
        self.head_buffer = 1024
        self.coding = 'utf-8'
        self.server = socket(AF_INET, SOCK_STREAM)
        self.server.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)
        self.server.bind(ip_bind)
        self.server.listen(50)
        self.server.setblocking(False)   #  非阻塞模型IO
        self.connect_list = []
        self.recv_list = []
        self.send_list = []
        self.disconnect_list = []

    def run(self):
        while 1:
            self.connect()
            self.recv()
            self.work()
            self.send()
            self.end()

    def connect(self):
        try:
            conn, address_link = self.server.accept()  # 没链接会弹出异常
            self.connect_list.append(conn)
        except BlockingIOError:
            return

    def recv(self):
        for conn in self.connect_list:
            try:
                msg = conn.recv(self.head_buffer)
                if not msg:
                    self.disconnect_list.append(conn)
                    return
                data = msg.decode(self.coding)
                self.recv_list.append((conn, data))
            except BlockingIOError:
                continue
            except Exception:
                self.disconnect_list.append(conn)

    def work(self):
        del_list = []
        for conn, msg in self.recv_list:
            self.send_list.append((conn, msg.upper()))
            del_list.append((conn, msg))
        for msg in del_list:
            self.recv_list.remove(msg)

    def send(self):
        del_list = []
        print(self.send_list)
        for conn, data in self.send_list:
            try:
                conn.send(data.encode(self.coding))
                del_list.append((conn,data))
            except BlockingIOError:
                continue
        for msg in del_list:
            self.send_list.remove(msg)

    def end(self):
        del_list = []
        for conn in self.disconnect_list:
            self.connect_list.remove(conn)
            conn.close()
            del_list.append(conn)

        for conn in del_list:
            self.recv_list.remove(conn)


if __name__ == '__main__':
    s = Server()
    s.run()