python网络爬虫实战——实时抓取西刺免费代理ip

参考网上高手示例程序，利用了多线程技术，Python版本为2.7

#-*-coding:utf8-*-

import urllib2
import re
import threading
import time

rawProxyList = []
checkedProxyList = []

#抓取代理网站
targets=[]
for i in range(1,6):
    target = r"http://www.xici.net.co/nn/%d" % i
    targets.append(target)
# print targets

#正则
p = re.compile(r'''<tr class=".+?(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})</td>.+?(\d{2,4})</td>.+?<td>(.{4,5})</td>''',re.DOTALL)

#获取代理的类
class ProxyGet(threading.Thread):
    def __init__(self,target):
        threading.Thread.__init__(self)
        self.target = target

    def getProxy(self):
        print "目标网站："+self.target
        req = urllib2.urlopen(self.target)
        result = req.read()
        matchs = p.findall(result)
        for row in matchs:
            ip = row[0]
            port = row[1]
            agent = row[2]
            addr=agent+'://'+ip+':'+port
            proxy = [ip,port,addr]
            rawProxyList.append(proxy)

    def run(self):
        self.getProxy()

#检验代理类
class ProxyCheck(threading.Thread):
    def __init__(self,proxyList):
        threading.Thread.__init__(self)
        self.proxyList = proxyList
        self.timeout=5
        self.testUrl = "http://www.baidu.com/"
        self.testStr = "030173"

    def checkProxy(self):
        cookies = urllib2.HTTPCookieProcessor()
        for proxy in self.proxyList:
            proxyHandler = urllib2.ProxyHandler({"http" : r'http://%s:%s' %(proxy[0],proxy[1])})
            opener=urllib2.build_opener(cookies,proxyHandler)
            opener.addheaders =[('User-Agent','Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/31.0.1650.63 Safari/537.36')]
            t1 = time.time()
            try:
                req = opener.open(self.testUrl,timeout=self.timeout)
                result=req.read()
                timeused = time.time()-t1
                pos = result.find(self.testStr)

                if pos > 1:
                    checkedProxyList.append((proxy[0],proxy[1],proxy[2],timeused))
                else:
                    continue
            except Exception,e:
                continue

    def run(self):
        self.checkProxy()

if __name__ == "__main__":
    getThreads=[]
    checkThreads=[]

#对每个目标网站开启一个线程负责抓取代理
for i in range(len(targets)):
    t = ProxyGet(targets[i])
    getThreads.append(t)

for i in range(len(getThreads)):
    getThreads[i].start()

for i in range(len(getThreads)):
    getThreads[i].join()

print '.'*10+"总共抓取了%s个代理" %len(rawProxyList) +'.'*10

#开启20个线程负责校验，将抓取到的代理分成20份，每个线程校验一份
for i in range(20):
    t = ProxyCheck(rawProxyList[((len(rawProxyList)+19)/20) * i:((len(rawProxyList)+19)/20) * (i+1)])
    checkThreads.append(t)

for i in range(len(checkThreads)):
    checkThreads[i].start()

for i in range(len(checkThreads)):
    checkThreads[i].join()

print '.'*10+"总共有%s个代理通过校验" %len(checkedProxyList) +'.'*10

#持久化
f= open("proxy_list.txt",'w+')
for proxy in sorted(checkedProxyList,cmp=lambda x,y:cmp(x[3],y[3])):
    print "checked proxy is: %s:%s\t%s\t%s" %(proxy[0],proxy[1],proxy[2],proxy[3])
    f.write("%s:%s\t%s\t%s\n"%(proxy[0],proxy[1],proxy[2],proxy[3]))
f.close()