python爬虫实战（四）--------豆瓣网的模拟登录（模拟登录和验证码的处理----scrapy）

在利用scrapy框架爬各种网站时，一定会碰到某些网站是需要登录才能获取信息。

这两天也在学习怎么去模拟登录，通过自己码的代码和借鉴别人的项目，调试成功豆瓣的模拟登录，顺便处理了怎么自动化的处理验证码。

一般都是通过打码平台处理的，当然你也可以机器学习的知识去识别验证码。后期我想自己做一个关于机器学习识别验证码的API，训练主流的网站，方便自己调用。（还不知道能不能做出来呢，走一步看一步咯！）

思路

一、想要实现登录豆瓣关键点

1. 分析真实post地址 ----寻找它的formdata，如下图,按浏览器的F12可以找到。
   
2. 模拟post ----构造类似的formdata
3. 验证码处理 ----打码平台

实战操作

相关代码已经调试成功----2017-4-5

目标网站：豆瓣网

实现：模拟登录豆瓣，验证码处理，登录到个人主页就算是success

数据：没有抓取数据，此实战主要是模拟登录和处理验证码的学习。要是有需求要抓取数据，编写相关的抓取规则即可抓取内容。

登录成功展示如图：

我在这里贴出主要代码，完整代码请移步我的github：https://github.com/pujinxiao/douban_login

spiders文件夹中DouBan.py主要代码如下：

# -*- coding: utf-8 -*-
import scrapy,urllib,re
from scrapy.http import Request,FormRequest
import ruokuai
class DoubanSpider(scrapy.Spider):
    name = "DouBan"
    allowed_domains = ["douban.com"]
    #start_urls = ['http://douban.com/']
    header={"User-Agent":"Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/56.0.2924.87 Safari/537.36"} #供登录模拟使用
    def start_requests(self):
        url='https://www.douban.com/accounts/login'
        return [Request(url=url,meta={"cookiejar":1},callback=self.parse)]#可以传递一个标示符来使用多个。如meta={'cookiejar': 1}这句，后面那个1就是标示符

    def parse(self, response):
        captcha=response.xpath('//*[@id="captcha_image"]/@src').extract()  #获取验证码图片的链接
        print captcha
        if len(captcha)>0:
            '''此时有验证码'''
            #人工输入验证码
            #urllib.urlretrieve(captcha[0],filename="C:/Users/pujinxiao/Desktop/learn/douban20170405/douban/douban/spiders/captcha.png")
            #captcha_value=raw_input('查看captcha.png,有验证码请输入:')

            #用快若打码平台处理验证码--------验证码是任意长度字母，成功率较低
            captcha_value=ruokuai.get_captcha(captcha[0])
            reg=r'<Result>(.*?)</Result>'
            reg=re.compile(reg)
            captcha_value=re.findall(reg,captcha_value)[0]
            print '验证码为：',captcha_value

            data={
                "form_email": "weisuen007@163.com",
                "form_password": "weijc7789",
                "captcha-solution": captcha_value,
                #"redir": "https://www.douban.com/people/151968962/",      #设置需要转向的网址，由于我们需要爬取个人中心页，所以转向个人中心页
            }
        else:
            '''此时没有验证码'''
            print '无验证码'
            data={
                "form_email": "weisuen007@163.com",
                "form_password": "weijc7789",
                #"redir": "https://www.douban.com/people/151968962/",
            }
        print '正在登陆中......'
        ####FormRequest.from_response()进行登陆
        return [
            FormRequest.from_response(
                response,
                meta={"cookiejar":response.meta["cookiejar"]},
                headers=self.header,
                formdata=data,
                callback=self.get_content,
            )
        ]
    def get_content(self,response):
        title=response.xpath('//title/text()').extract()[0]
        if u'登录豆瓣' in title:
            print '登录失败，请重试！'
        else:
            print '登录成功'
            '''
            可以继续后续的爬取工作
            '''

ruokaui.py代码如下：

我所用的是若块打码平台，选择url识别验证码，直接给打码平台验证码图片的链接地址，传回验证码的值。

# -*- coding: utf-8 -*-
import sys, hashlib, os, random, urllib, urllib2
from datetime import *

class APIClient(object):
    def http_request(self, url, paramDict):
        post_content = ''
        for key in paramDict:
            post_content = post_content + '%s=%s&'%(key,paramDict[key])
        post_content = post_content[0:-1]
        #print post_content
        req = urllib2.Request(url, data=post_content)
        req.add_header('Content-Type', 'application/x-www-form-urlencoded')
        opener = urllib2.build_opener(urllib2.HTTPCookieProcessor())  
        response = opener.open(req, post_content)  
        return response.read()

    def http_upload_image(self, url, paramKeys, paramDict, filebytes):
        timestr = datetime.now().strftime('%Y-%m-%d %H:%M:%S')
        boundary = '------------' + hashlib.md5(timestr).hexdigest().lower()
        boundarystr = '\r\n--%s\r\n'%(boundary)
        
        bs = b''
        for key in paramKeys:
            bs = bs + boundarystr.encode('ascii')
            param = "Content-Disposition: form-data; name=\"%s\"\r\n\r\n%s"%(key, paramDict[key])
            #print param
            bs = bs + param.encode('utf8')
        bs = bs + boundarystr.encode('ascii')
        
        header = 'Content-Disposition: form-data; name=\"image\"; filename=\"%s\"\r\nContent-Type: image/gif\r\n\r\n'%('sample')
        bs = bs + header.encode('utf8')
        
        bs = bs + filebytes
        tailer = '\r\n--%s--\r\n'%(boundary)
        bs = bs + tailer.encode('ascii')
        
        import requests
        headers = {'Content-Type':'multipart/form-data; boundary=%s'%boundary,
                   'Connection':'Keep-Alive',
                   'Expect':'100-continue',
                   }
        response = requests.post(url, params='', data=bs, headers=headers)
        return response.text

def arguments_to_dict(args):
    argDict = {}
    if args is None:
        return argDict
    
    count = len(args)
    if count <= 1:
        print 'exit:need arguments.'
        return argDict
    
    for i in [1,count-1]:
        pair = args[i].split('=')
        if len(pair) < 2:
            continue
        else:
            argDict[pair[0]] = pair[1]

    return argDict

def get_captcha(image_url):
    client = APIClient()
    while 1:
        paramDict = {}
        result = ''
        act = raw_input('请输入打码方式url:')
        if cmp(act, 'info') == 0: 
            paramDict['username'] = raw_input('username:')
            paramDict['password'] = raw_input('password:')
            result = client.http_request('http://api.ruokuai.com/info.xml', paramDict)
        elif cmp(act, 'register') == 0:
            paramDict['username'] = raw_input('username:')
            paramDict['password'] = raw_input('password:')
            paramDict['email'] = raw_input('email:')
            result = client.http_request('http://api.ruokuai.com/register.xml', paramDict)
        elif cmp(act, 'recharge') == 0:
            paramDict['username'] = raw_input('username:')
            paramDict['id'] = raw_input('id:')
            paramDict['password'] = raw_input('password:')
            result = client.http_request('http://api.ruokuai.com/recharge.xml', paramDict)
        elif cmp(act, 'url') == 0:
            paramDict['username'] = '********'
            paramDict['password'] = '********'
            paramDict['typeid'] = '2000'
            paramDict['timeout'] = '90'
            paramDict['softid'] = '76693'
            paramDict['softkey'] = 'ec2b5b2a576840619bc885a47a025ef6'
            paramDict['imageurl'] = image_url
            result = client.http_request('http://api.ruokuai.com/create.xml', paramDict)
        elif cmp(act, 'report') == 0:
            paramDict['username'] = raw_input('username:')
            paramDict['password'] = raw_input('password:')
            paramDict['id'] = raw_input('id:')
            result = client.http_request('http://api.ruokuai.com/create.xml', paramDict)
        elif cmp(act, 'upload') == 0:
            paramDict['username'] = '********'
            paramDict['password'] = '********'
            paramDict['typeid'] = '2000'
            paramDict['timeout'] = '90'
            paramDict['softid'] = '76693'
            paramDict['softkey'] = 'ec2b5b2a576840619bc885a47a025ef6'
            paramKeys = ['username',
                 'password',
                 'typeid',
                 'timeout',
                 'softid',
                 'softkey'
                ]

            from PIL import Image
            imagePath = raw_input('Image Path:')
            img = Image.open(imagePath)
            if img is None:
                print 'get file error!'
                continue
            img.save("upload.gif", format="gif")
            filebytes = open("upload.gif", "rb").read()
            result = client.http_upload_image("http://api.ruokuai.com/create.xml", paramKeys, paramDict, filebytes)
        
        elif cmp(act, 'help') == 0:
            print 'info'
            print 'register'
            print 'recharge'
            print 'url'
            print 'report'
            print 'upload'
            print 'help'
            print 'exit'
        elif cmp(act, 'exit') == 0:
            break
        
        return result

 笔记

知识点：

1. return Request的用法
   return [Request(url=url,meta={"cookiejar":1},callback=self.parse)]   #可以传递一个标示符来使用多个。如meta={'cookiejar': 1}这句，后面那个1就是标示符
2. 打码平台的使用
   直接利用验证码图片的url接口即可
3. FormRequest的用法
   

   return [
       FormRequest.from_response(
           response,
           meta={"cookiejar":response.meta["cookiejar"]},
           headers=self.header,
           formdata=data,
           callback=self.get_content,
       )
   ]

作者：今孝
出处：http://www.cnblogs.com/jinxiao-pu/p/6670672.html
本文版权归作者和博客园共有，欢迎转载，但未经作者同意必须保留此段声明，且在文章页面明显位置给出原文连接。