Python学习，gevent协程，多线程，多进程demo

二爷

发布于 2021-09-15 10:58:18

6880

发布于 2021-09-15 10:58:18

文章被收录于专栏：二爷记二爷记二爷记

协程，线程，进程，多线程，多进程，线程池，本渣渣是彻底蒙蔽了，不过干就是了，二话不说写（抄）代码就是了，抄多了就明了了，说错了，写多了就会了！

关于gevent

Python通过yield提供了对协程的基本支持，但是不完全。而第三方的gevent为Python提供了比较完善的协程支持。

gevent是第三方库，通过greenlet实现协程，其基本思想是：

当一个greenlet遇到IO操作时，比如访问网络，就自动切换到其他的greenlet，等到IO操作完成，再在适当的时候切换回来继续执行。由于IO操作非常耗时，经常使程序处于等待状态，有了gevent为我们自动切换协程，就保证总有greenlet在运行，而不是等待IO。

greenlet是依次运行而不是交替运行。

要让greenlet交替运行，可以通过gevent.sleep()交出控制权

来源：廖雪峰博客

关于put_nowait与get_nowait

put与get方法是两个阻塞方法：put不到值程序夯住，get不到程序也夯住。

put_nowait与get_nowait方法是两个非阻塞方法：put_nowait没有值的话不等，get_nowait取不到值也不等了，程序不会夯住，但是一定要做异常处理！

demo参考

#犀牛原厂
# -*- coding: utf-8 -*-
#20210827 微信：huguo00289
import requests
import random
from lxml import etree
from gevent import monkey
monkey.patch_socket()
import gevent
from gevent.queue import Queue
import time
import threading
import queue
from multiprocessing import Process
import multiprocessing



# 随机获取一个请求头
def get_user_agent():
    user_agent = [
        "Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_6_8; en-us) AppleWebKit/534.50 (KHTML, like Gecko) Version/5.1 Safari/534.50",
        "Mozilla/5.0 (Windows; U; Windows NT 6.1; en-us) AppleWebKit/534.50 (KHTML, like Gecko) Version/5.1 Safari/534.50",
        "Mozilla/5.0 (Windows NT 10.0; WOW64; rv:38.0) Gecko/20100101 Firefox/38.0",
        "Mozilla/5.0 (Windows NT 10.0; WOW64; Trident/7.0; .NET4.0C; .NET4.0E; .NET CLR 2.0.50727; .NET CLR 3.0.30729; .NET CLR 3.5.30729; InfoPath.3; rv:11.0) like Gecko",
        "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0)",
        "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.0; Trident/4.0)",
        "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0)",
        "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1)",
        "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:2.0.1) Gecko/20100101 Firefox/4.0.1",
        "Mozilla/5.0 (Windows NT 6.1; rv:2.0.1) Gecko/20100101 Firefox/4.0.1",
        "Opera/9.80 (Macintosh; Intel Mac OS X 10.6.8; U; en) Presto/2.8.131 Version/11.11",
        "Opera/9.80 (Windows NT 6.1; U; en) Presto/2.8.131 Version/11.11",
        "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_7_0) AppleWebKit/535.11 (KHTML, like Gecko) Chrome/17.0.963.56 Safari/535.11",
        "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Maxthon 2.0)",
        "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; TencentTraveler 4.0)",
        "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1)",
        "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; The World)",
        "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Trident/4.0; SE 2.X MetaSr 1.0; SE 2.X MetaSr 1.0; .NET CLR 2.0.50727; SE 2.X MetaSr 1.0)",
        "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; 360SE)",
        "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Avant Browser)",
        "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1)",
        "Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_3_3 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8J2 Safari/6533.18.5",
        "Mozilla/5.0 (iPod; U; CPU iPhone OS 4_3_3 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8J2 Safari/6533.18.5",
        "Mozilla/5.0 (iPad; U; CPU OS 4_3_3 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8J2 Safari/6533.18.5",
        "Mozilla/5.0 (Linux; U; Android 2.3.7; en-us; Nexus One Build/FRF91) AppleWebKit/533.1 (KHTML, like Gecko) Version/4.0 Mobile Safari/533.1",
        "MQQBrowser/26 Mozilla/5.0 (Linux; U; Android 2.3.7; zh-cn; MB200 Build/GRJ22; CyanogenMod-7) AppleWebKit/533.1 (KHTML, like Gecko) Version/4.0 Mobile Safari/533.1",
        "Opera/9.80 (Android 2.3.4; Linux; Opera Mobi/build-1107180945; U; en-GB) Presto/2.8.149 Version/11.10",
        "Mozilla/5.0 (Linux; U; Android 3.0; en-us; Xoom Build/HRI39) AppleWebKit/534.13 (KHTML, like Gecko) Version/4.0 Safari/534.13",
        "Mozilla/5.0 (BlackBerry; U; BlackBerry 9800; en) AppleWebKit/534.1+ (KHTML, like Gecko) Version/6.0.0.337 Mobile Safari/534.1+",
        "Mozilla/5.0 (hp-tablet; Linux; hpwOS/3.0.0; U; en-US) AppleWebKit/534.6 (KHTML, like Gecko) wOSBrowser/233.70 Safari/534.6 TouchPad/1.0",
        "Mozilla/5.0 (SymbianOS/9.4; Series60/5.0 NokiaN97-1/20.0.019; Profile/MIDP-2.1 Configuration/CLDC-1.1) AppleWebKit/525 (KHTML, like Gecko) BrowserNG/7.1.18124",
        "Mozilla/5.0 (compatible; MSIE 9.0; Windows Phone OS 7.5; Trident/5.0; IEMobile/9.0; HTC; Titan)",
        "UCWEB7.0.2.37/28/999",
        "NOKIA5700/ UCWEB7.0.2.37/28/999",
        "Openwave/ UCWEB7.0.2.37/28/999",
        "Mozilla/4.0 (compatible; MSIE 6.0; ) Opera/UCWEB7.0.2.37/28/999",
        # iPhone 6：
        "Mozilla/6.0 (iPhone; CPU iPhone OS 8_0 like Mac OS X) AppleWebKit/536.26 (KHTML, like Gecko) Version/8.0 Mobile/10A5376e Safari/8536.25",

    ]

    headers = {'User-Agent': random.choice(user_agent)}
    return headers


def get_urllist(url):
    html=requests.get(url=url,headers=get_user_agent(),timeout=6).content.decode('utf-8')
    tree=etree.HTML(html)
    hrefs=tree.xpath('//div[@class="deanpiclicr"]/h2/a/@href')
    # print(len(hrefs))
    print(hrefs)

urls_work = Queue()
for i in range(1, 28):
    url = "https://www.rhino3d.asia/portal.php?mod=list&catid=1&page=%d" % i
    urls_work.put_nowait(url)


def get_url_pool():
    while not urls_work.empty():
        url = urls_work.get_nowait()
        get_urllist(url)


def ge():
    startTime=time.time()
    tasks_list = []
    for x in range(5):
        task = gevent.spawn(get_url_pool)
        tasks_list.append(task)
    gevent.joinall(tasks_list)
    endTime = time.time()
    print('gevent用时：',endTime-startTime)



def pe():
    startTime = time.time()
    for i in range(1, 28):
        url = "https://www.rhino3d.asia/portal.php?mod=list&catid=1&page=%d" % i
        get_urllist(url)
    endTime = time.time()
    print('单线程用时：', endTime - startTime)


# 创建队列
q = queue.Queue()
for i in range(1, 28):
    url = "https://www.rhino3d.asia/portal.php?mod=list&catid=1&page=%d" % i
    q.put(url)


def th_pool():
    while not q.empty():
        url = q.get()
        get_urllist(url)


def run():
    startTime = time.time()
    threads = []
    for x in range(5):
        t = threading.Thread(target=th_pool)
        threads.append(t)

    for i in threads:
        i.start()
    for i in threads:
        i.join()

    endTime = time.time()
    print('多线程用时：', endTime - startTime)


def prun():
    startTime = time.time()
    pros = []
    for x in range(5):
        t = Process(target=th_pool)
        pros.append(t)

    for i in pros:
        i.start()
    for i in pros:
        i.join()

    endTime = time.time()
    print('多进程用时：', endTime - startTime)


def pprun():
    startTime = time.time()
    pool = multiprocessing.Pool(processes=4) #进程池设置了4个进行
    for i in range(1, 28):
        url = "https://www.rhino3d.asia/portal.php?mod=list&catid=1&page=%d" % i
        pool.apply_async(func=get_urllist, args=(url,))
    pool.close()
    pool.join()
    endTime = time.time()
    print('多进程用时：', endTime - startTime)




if __name__=='__main__':
    pe()  #单线程
    ge()  #协程
    run() #多线程
    #prun()  #未成功多进程
    pprun() #线程池多进程