将socket通信变成并发的方式

一 利用multiprocessing模块，开启多进程，实现socket通信并发

1. 开启子进程的两种方式

import time
import random
from multiprocessing import Process
def piao(name):
    print('%s piaoing' %name)
    time.sleep(random.randrange(1,5))
    print('%s piao end' %name)



p1=Process(target=piao,args=('egon',)) #必须加,号
p2=Process(target=piao,args=('alex',))
p3=Process(target=piao,args=('wupeqi',))
p4=Process(target=piao,args=('yuanhao',))

p1.start()
p2.start()
p3.start()
p4.start()
print('主线程')

#开进程的方法二:
import time
import random
from multiprocessing import Process


class Piao(Process):  #注意一定要继承Process
    def __init__(self,name):
        super().__init__()
        self.name=name
    def run(self):
        print('%s piaoing' %self.name)

        time.sleep(random.randrange(1,5))
        print('%s piao end' %self.name)

p1=Piao('egon')
p2=Piao('alex')
p3=Piao('wupeiqi')
p4=Piao('yuanhao')

p1.start() #start会自动调用run
p2.start()
p3.start()
p4.start()
print('主进程')

2.多进程实现socket并发通信

服务端

from socket import *
from multiprocessing import Process

server=socket(AF_INET,SOCK_STREAM)
server.setsockopt(SOL_SOCKET,SO_REUSEADDR,1)
server.bind(('127.0.0.1',8081))
server.listen(5)

def talk(conn,client_addr):
    while True:
        try:     #若不用此句，客户端关闭时，服务端会因报错，停止
            msg=conn.recv(1024)
            if not msg:break
            conn.send(msg.upper())
        except Exception:
            break

if __name__ == '__main__': #windows下start进程一定要写到这下面
    while True:
        conn,client_addr=server.accept()
        p=Process(target=talk,args=(conn,client_addr))
        p.start()

客户端

from socket import *

client=socket(AF_INET,SOCK_STREAM)
client.connect(('127.0.0.1',8081))


while True:
    msg=input('>>: ').strip()
    if not msg:
        continue
    client.send(msg.encode('utf-8'))
    msg=client.recv(1024)
    print(msg.decode('utf-8'))

存在的问题：每来一个客户端，都在服务端开启一个进程，如果并发来一个万个客户端，要开启一万个进程吗，你自己尝试着在你自己的机器上开启一万个，10万个进程试一试。

解决办法：进程池3 进程池实现并发通信

3 进程池实现并发通信

使用进程池维护固定数目的进程

#Pool内的进程数默认是cpu核数，假设为4（查看方法os.cpu_count()）
#开启6个客户端，会发现2个客户端处于等待状态
#在每个进程内查看pid，会发现pid使用为4个，即多个客户端公用4个进程
from socket import *
from multiprocessing import Pool
import os

server=socket(AF_INET,SOCK_STREAM)
server.setsockopt(SOL_SOCKET,SO_REUSEADDR,1)
server.bind(('127.0.0.1',8080))
server.listen(5)

def talk(conn,client_addr):
    print('进程pid: %s' %os.getpid())
    while True:
        try:
            msg=conn.recv(1024)
            if not msg:break
            conn.send(msg.upper())
        except Exception:
            break

if __name__ == '__main__':
    p=Pool()
    while True:
        conn,client_addr=server.accept()
        p.apply_async(talk,args=(conn,client_addr))
        # p.apply(talk,args=(conn,client_addr)) #同步的话，则同一时间只有一个客户端能访问

from socket import *

client=socket(AF_INET,SOCK_STREAM)
client.connect(('127.0.0.1',8081))


while True:
    msg=input('>>: ').strip()
    if not msg:
        continue
    client.send(msg.encode('utf-8'))
    msg=client.recv(1024)
    print(msg.decode('utf-8'))

发现：并发开启多个客户端，服务端同一时间只有4个不同的pid，干掉一个客户端，另外一个客户端才会进来，被3个进程之一处理

二 利用threading模块，开启多线程，实现socket通信并发

1. 开启多线程的两种方式

#方式一
from threading import Thread
import time
def sayhi(name):
    time.sleep(2)
    print('%s say hello' %name)

if __name__ == '__main__':
    t=Thread(target=sayhi,args=('egon',))
    t.start()
    print('主线程')

#方式二
from threading import Thread
import time
class Sayhi(Thread):   #注意继承Thread类
    def __init__(self,name):
        super().__init__()
        self.name=name
    def run(self):
        time.sleep(2)
        print('%s say hello' % self.name)


if __name__ == '__main__':
    t = Sayhi('egon')
    t.start()
    print('主线程')

2.多进程实现socket并发通信

服务端

from threading import Thread
from socket import *


server=socket(AF_INET,SOCK_STREAM)
server.setsockopt(SOL_SOCKET,SO_REUSEADDR,1)
server.bind(('127.0.0.1',8081))
server.listen(5)

def talk(conn,addr):
    while True:
        try:
            msg=conn.recv(1024)
            if not msg:
                break
            conn.send(msg.upper())
        except Exception:
            break

if __name__ == '__main__':
    while True:
        conn,addr=server.accept()
        t=Thread(target=talk,args=(conn,addr))
        t.start()

 客户端

from socket import *

client=socket(AF_INET,SOCK_STREAM)
client.connect(('127.0.0.1',8081))


while True:
    msg=input('>>: ').strip()
    if not msg:
        continue
    client.send(msg.encode('utf-8'))
    msg=client.recv(1024)
    print(msg.decode('utf-8'))

三 利用concurrent模块，开启进程池、线程池实现socket通信并发

 1. 进程池

服务端

from concurrent.futures import ProcessPoolExecutor
from socket import *

server=socket(AF_INET,SOCK_STREAM)
server.setsockopt(SOL_SOCKET,SO_REUSEADDR,1)
server.bind(('127.0.0.1',8081))
server.listen(5)

def talk(conn,addr):
    while True:
        try:
            msg=conn.recv(1024)
            if not msg:
                break
            conn.send(msg.upper())
        except Exception:
            break

if __name__ == '__main__':
    p=ProcessPoolExecutor()  #不填则默认为cpu的个数
    while True:
        conn,addr=server.accept()
        p.submit(talk,conn,addr)

客户端

from socket import *

client=socket(AF_INET,SOCK_STREAM)
client.connect(('127.0.0.1',8081))


while True:
    msg=input('>>: ').strip()
    if not msg:
        continue
    client.send(msg.encode('utf-8'))
    msg=client.recv(1024)
    print(msg.decode('utf-8'))

2. 线程池

服务端

from concurrent.futures import ThreadPoolExecutor
from socket import *

server=socket(AF_INET,SOCK_STREAM)
server.setsockopt(SOL_SOCKET,SO_REUSEADDR,1)
server.bind(('127.0.0.1',8081))
server.listen(5)

def talk(conn,addr):
    while True:
        try:
            msg=conn.recv(1024)
            if not msg:
                break
            conn.send(msg.upper())
        except Exception:
            break

if __name__ == '__main__':
    p=ThreadPoolExecutor()  #不填则默认为cpu的个数*5
    while True:
        conn,addr=server.accept()
        p.submit(talk,conn,addr)

客户端

from socket import *

client=socket(AF_INET,SOCK_STREAM)
client.connect(('127.0.0.1',8081))


while True:
    msg=input('>>: ').strip()
    if not msg:
        continue
    client.send(msg.encode('utf-8'))
    msg=client.recv(1024)
    print(msg.decode('utf-8'))

四 利用gevent模块，协程实现单线程下的socket通信并发

 通过gevent实现单线程下的socket并发（from gevent import monkey;monkey.patch_all()一定要放到导入socket模块之前，否则gevent无法识别socket的阻塞）

from gevent import monkey;monkey.patch_all()
from socket import *
import gevent

#如果不想用money.patch_all()打补丁,可以用gevent自带的socket
# from gevent import socket
# s=socket.socket()

def server(server_ip,port):
    s=socket(AF_INET,SOCK_STREAM)
    s.setsockopt(SOL_SOCKET,SO_REUSEADDR,1)
    s.bind((server_ip,port))
    s.listen(5)
    while True:
        conn,addr=s.accept()
        gevent.spawn(talk,conn,addr)

def talk(conn,addr):
    try:
        while True:
            res=conn.recv(1024)
            print('client %s:%s msg: %s' %(addr[0],addr[1],res))
            conn.send(res.upper())
    except Exception as e:
        print(e)
    finally:
        conn.close()

if __name__ == '__main__':
    server('127.0.0.1',8080)

from socket import *

client=socket(AF_INET,SOCK_STREAM)
client.connect(('127.0.0.1',8080))


while True:
    msg=input('>>: ').strip()
    if not msg:continue

    client.send(msg.encode('utf-8'))
    msg=client.recv(1024)
    print(msg.decode('utf-8'))

from threading import Thread
from socket import *
import threading

def client(server_ip,port):
    c=socket(AF_INET,SOCK_STREAM) #套接字对象一定要加到函数内，即局部名称空间内，放在函数外则被所有线程共享，则大家公用一个套接字对象，那么客户端端口永远一样了
    c.connect((server_ip,port))

    count=0
    while True:
        c.send(('%s say hello %s' %(threading.current_thread().getName(),count)).encode('utf-8'))
        msg=c.recv(1024)
        print(msg.decode('utf-8'))
        count+=1
if __name__ == '__main__':
    for i in range(500):
        t=Thread(target=client,args=('127.0.0.1',8080))
        t.start()

 五 利用selectors模块，实现socket并发通信

selectors模块，帮我们默认选择当前平台下最合适的IO多路复用模型（select、poll和epoll）

#服务端
from socket import *
import selectors

sel=selectors.DefaultSelector()
def accept(server_fileobj,mask):
    conn,addr=server_fileobj.accept()
    sel.register(conn,selectors.EVENT_READ,read)

def read(conn,mask):
    try:
        data=conn.recv(1024)
        if not data:
            print('closing',conn)
            sel.unregister(conn)
            conn.close()
            return
        conn.send(data.upper()+b'_SB')
    except Exception:
        print('closing', conn)
        sel.unregister(conn)
        conn.close()



server_fileobj=socket(AF_INET,SOCK_STREAM)
server_fileobj.setsockopt(SOL_SOCKET,SO_REUSEADDR,1)
server_fileobj.bind(('127.0.0.1',8088))
server_fileobj.listen(5)
server_fileobj.setblocking(False) #设置socket的接口为非阻塞
sel.register(server_fileobj,selectors.EVENT_READ,accept) #相当于网select的读列表里append了一个文件句柄server_fileobj,并且绑定了一个回调函数accept

while True:
    events=sel.select() #检测所有的fileobj，是否有完成wait data的
    for sel_obj,mask in events:
        callback=sel_obj.data #callback=accpet
        callback(sel_obj.fileobj,mask) #accpet(server_fileobj,1)

#客户端
from socket import *
c=socket(AF_INET,SOCK_STREAM)
c.connect(('127.0.0.1',8088))

while True:
    msg=input('>>: ')
    if not msg:continue
    c.send(msg.encode('utf-8'))
    data=c.recv(1024)
    print(data.decode('utf-8'))