urilib2檢驗代理IP

爬蟲筆記---IP代理檢驗

#!/usr/bin/env python
#-*- coding: utf-8 -*-

import urllib2
import sys
import re

def testArgument():
	'''測試輸入測試IP地址，只需要一個參數 '''
	if len(sys.argv) != 2:
		print(u'只需要一個參數就夠了')
		tipUse()
		exit()
	else:
		TP = TestProxy(sys.argv[1])

def tipUse():
	'''顯示提示信息 '''
	print(u'該程序只能輸入一個參數，這個參數必須是一個可用的proxy')
	print(u'usage: python testUrllib2WithProxy.py http://1.2.3.4:5')
	print(u'usage: python testUrllib2WithProxy.py https://1.2.3.4:5')
	

class TestProxy(object):
	'''這個類的作用是測試proxy是否有效 '''
	def __init__(self,proxy):
		self.proxy = proxy
		self.checkProxyFormat(self.proxy)
		self.url = 'http://www.baidu.com'
		self.timeout = 5 
		self.flagWord = '百度' #在網頁返回的數據中查找這個關鍵詞
		self.useProxy(self.proxy)

	def checkProxyFormat(self,proxy):
		try:
			proxyMatch = re.compile('http[s]?://[\d]{1,3}\.[\d]{1,3}\.[\d]{1,3}\.[\d]{1,3}:[\d]{1,5}$')
			re.search(proxyMatch,proxy).group()
		except AttributeError:
			tipUse()
			exit()
		flag = 1
		proxy = proxy.replace('//','')
		try:
			protocol = proxy.split(':')[0]
			ip = proxy.split(':')[1]
			port = proxy.split(':')[2]
		except IndexError:
			print(u'下標出界')
			tipUse()
			exit()
		flag = flag and len(proxy.split(':')) == 3 and len(ip.split('.')) == 4
		flag = ip.split('.')[0] in map(str,xrange(1,256)) and flag
		flag = ip.split('.')[1] in map(str,xrange(256)) and flag
		flag = ip.split('.')[2] in map(str,xrange(256)) and flag
		flag = ip.split('.')[3] in map(str,xrange(1,255)) and flag
		flag = protocol in [u'http',u'https'] and flag
		flag = port in map(str,range(1,65535)) and flag
		'''這裏是在檢查proxy的格式 '''
		if flag:
			print(u'輸入的http代理服務器符合標準')
		else:
			tipUse()
			exit()		

	def useProxy(self,proxy):
		'''利用代理訪問百度，並查找關鍵詞 '''
		protocol = proxy.split('//')[0].replace(':','')
		ip = proxy.split('//')[1]
		opener = urllib2.build_opener(urllib2.ProxyHandler({protocol:ip}))
		urllib2.install_opener(opener)
		try:
			response = urllib2.urlopen(self.url,timeout = self.timeout)
		except:
			print(u'連接錯誤，退出程序')
			exit()
		str = response.read()
		if re.search(self.flagWord,str):
			print(u'已取得特徵詞，該代理可用')
		else:
			print(u'該代理不可用')

		
if __name__ == '__main__':
	testArgument()	

這個程序也可以作爲模塊導入到其他程序中,比如檢驗爬取的IP是否可用。。。