进程池与线程池例子（异步调用与回调）

多线程下载网站数据

from concurrent.futures import ThreadPoolExecutor
import time
import requests
def get(url):
    print("get %s" % url)
    response=requests.get(url)
    time.sleep(3)
    return {"url":url,"content":response.text}
def parse(res):
    res=res.result()
    print("%s parse res is %s" % (res['url'],len(res['content'])))

if __name__=="__main__":
    urls=[
        "http://fanyi.youdao.com/",
        "http://news.baidu.com/",
        "http://news.cctv.com/2018/05/16/ARTIjk8z8DQrpR7ciSzijCgl180516.shtml",
        "http://news.cctv.com/2018/05/16/ARTI43pH6clUqOHJfYaRgHri180516.shtml",
        "http://news.china.com/domestic/945/20180516/32417253.html?newsbaidu",
        "http://money.china.com/"
    ]
    pool=ThreadPoolExecutor(2)
    for url in urls:
        pool.submit(get,url).add_done_callback(parse)

get http://fanyi.youdao.com/
get http://news.baidu.com/
http://fanyi.youdao.com/ parse res is 18720
get http://news.cctv.com/2018/05/16/ARTIjk8z8DQrpR7ciSzijCgl180516.shtml
http://news.baidu.com/ parse res is 74087
get http://news.cctv.com/2018/05/16/ARTI43pH6clUqOHJfYaRgHri180516.shtml
http://news.cctv.com/2018/05/16/ARTIjk8z8DQrpR7ciSzijCgl180516.shtml parse res is 88508
get http://news.china.com/domestic/945/20180516/32417253.html?newsbaidu
http://news.cctv.com/2018/05/16/ARTI43pH6clUqOHJfYaRgHri180516.shtml parse res is 32127
get http://money.china.com/
http://news.china.com/domestic/945/20180516/32417253.html?newsbaidu parse res is 65824
http://money.china.com/ parse res is 63167

Process finished with exit code 0

线程池控制服务端线程数量

from socket import *
from concurrent.futures import ThreadPoolExecutor
def communicate(conn):
    while True:
        try:
            data = conn.recv(1024)
            if not data: break
            conn.send(data.upper())
        except ConnectionResetError:
            break
    conn.close()
def servers(ip,port):
    server = socket(AF_INET, SOCK_STREAM)
    server.bind((ip, port))
    server.listen(5)
    while True:
        conn,addr=server.accept()
        print(addr)
        pool.submit(communicate,conn)
    server.close()
if __name__=="__main__":
    pool=ThreadPoolExecutor(2)
    servers("127.0.0.1",8081)