selectors实现高并发

Posted 2020-08-12

1. 下面的例子，客户端给服务端发送消息，服务端把消息返回

server

#!/usr/bin/env python


import selectors
import socket
import time
import threading


sel = selectors.DefaultSelector()

def echo(conn,cmd,filename):
    time.sleep(3)
    conn.send((cmd + ‘ ‘ + filename).encode())

def accept_client(sock,mask):
    conn,addr = sock.accept()
    print(‘conn:{},addr:{},mask:{}‘.format(conn,addr,mask))
#     conn.setblocking(False)
    sel.register(conn, selectors.EVENT_READ, read_client)

def read_client(conn,mask):
    data = conn.recv(1024).decode().strip()
    if data:
        if len(data.split(‘ ‘)) == 2:
            cmd = data.split(‘ ‘)[0]
            filename = data.split(‘ ‘)[1]
            t = threading.Thread(target=echo,args=(conn,cmd,filename))   #这里使用了线程，不然程序会变成串行的，执行一个客户端任务，sleep(3)然后再执行下一个客户端任务...
            t.start()
#             time.sleep(1)
#             conn.send((cmd + ‘ ‘ + filename).encode())
        else:
            conn.send((‘usage: put filename ;get filename‘).encode())
    else:
        print(‘{} closed‘.format(conn))
        sel.unregister(conn)
        conn.close()
server = socket.socket()
server.bind((‘localhost‘,1235))
server.listen(12340)
# server.setblocking(False)
sel.register(server, selectors.EVENT_READ,accept_client)


while True:
    events = sel.select()
    for key,mask in events:
        callable = key.data
        callable(key.fileobj,mask)

client

#!/usr/bin/env python

import socket
import threading
import time

ip_port = (‘localhost‘,1235)
socks = [socket.socket() for i in range(1000)]        

m = b‘get abc‘
time_list = []
def run(s):
    s.connect(ip_port)
    s.send(m)
    data = s.recv(1024)
    print(s,data)
    
start_time = time.time()   
for s in socks:
    t = threading.Thread(target=run,args=(s,))
    t.start()
    time_list.append(t)
for i in time_list:
    i.join()
print(‘time:{}‘.format(start_time - time.time()))
    

2. 实现并发put和get文件