Python网页抓取urllib,urllib2,httplib[3]

使用urllib2，太强大了

试了下用代理登陆拉取cookie，跳转抓图片......

文档：http://docs.python.org/library/urllib2.html 

直接上demo代码了

包括：直接拉取，使用Reuqest(post/get),使用代理，cookie,跳转处理

#!/usr/bin/python
# -*- coding:utf-8 -*-
# urllib2_test.py
# author: wklken
# 2012-03-17 wklken@yeah.net


import urllib,urllib2,cookielib,socket

url = "http://www.testurl....." #change yourself
#最简单方式
def use_urllib2():
  try:
    f = urllib2.urlopen(url, timeout=5).read()
  except urllib2.URLError, e:
    print e.reason
  print len(f)

#使用Request
def get_request():
  #可以设置超时
  socket.setdefaulttimeout(5)
  #可以加入参数  [无参数，使用get，以下这种方式，使用post]
  params = {"wd":"a","b":"2"}
  #可以加入请求头信息，以便识别
  i_headers = {"User-Agent": "Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-CN; rv:1.9.1) Gecko/20090624 Firefox/3.5",
             "Accept": "text/plain"}
  #use post,have some params post to server,if not support ,will throw exception
  #req = urllib2.Request(url, data=urllib.urlencode(params), headers=i_headers)
  req = urllib2.Request(url, headers=i_headers)

  #创建request后，还可以进行其他添加,若是key重复，后者生效
  #request.add_header('Accept','application/json')
  #可以指定提交方式
  #request.get_method = lambda: 'PUT'
  try:
    page = urllib2.urlopen(req)
    print len(page.read())
    #like get
    #url_params = urllib.urlencode({"a":"1", "b":"2"})
    #final_url = url + "?" + url_params
    #print final_url
    #data = urllib2.urlopen(final_url).read()
    #print "Method:get ", len(data)
  except urllib2.HTTPError, e:
    print "Error Code:", e.code
  except urllib2.URLError, e:
    print "Error Reason:", e.reason

def use_proxy():
  enable_proxy = False
  proxy_handler = urllib2.ProxyHandler({"http":"http://proxyurlXXXX.com:8080"})
  null_proxy_handler = urllib2.ProxyHandler({})
  if enable_proxy:
    opener = urllib2.build_opener(proxy_handler, urllib2.HTTPHandler)
  else:
    opener = urllib2.build_opener(null_proxy_handler, urllib2.HTTPHandler)
  #此句设置urllib2的全局opener
  urllib2.install_opener(opener)
  content = urllib2.urlopen(url).read()
  print "proxy len:",len(content)

class NoExceptionCookieProcesser(urllib2.HTTPCookieProcessor):
  def http_error_403(self, req, fp, code, msg, hdrs):
    return fp
  def http_error_400(self, req, fp, code, msg, hdrs):
    return fp
  def http_error_500(self, req, fp, code, msg, hdrs):
    return fp

def hand_cookie():
  cookie = cookielib.CookieJar()
  #cookie_handler = urllib2.HTTPCookieProcessor(cookie)
  #after add error exception handler
  cookie_handler = NoExceptionCookieProcesser(cookie)
  opener = urllib2.build_opener(cookie_handler, urllib2.HTTPHandler)
  url_login = "https://www.yourwebsite/?login"
  params = {"username":"user","password":"111111"}
  opener.open(url_login, urllib.urlencode(params))
  for item in cookie:
    print item.name,item.value
  #urllib2.install_opener(opener)
  #content = urllib2.urlopen(url).read()
  #print len(content)
#得到重定向 N 次以后最后页面URL
def get_request_direct():
  import httplib
  httplib.HTTPConnection.debuglevel = 1
  request = urllib2.Request("http://www.google.com")
  request.add_header("Accept", "text/html,*/*")
  request.add_header("Connection", "Keep-Alive")
  opener = urllib2.build_opener()
  f = opener.open(request)
  print f.url
  print f.headers.dict
  print len(f.read())

if __name__ == "__main__":
  use_urllib2()
  get_request()
  get_request_direct()
  use_proxy()
  hand_cookie()