# _*_ coding: utf-8 _*_

 

'''

模拟知乎登陆并使用tesseract-ocr识别验证码

 

Author: Insomnia

Version: 0.0.1

Date: 2017-09-07

Language: Python3.6.2

Editor: Sublime Text3

'''

 

import requests, os, time, re

from bs4 import BeautifulSoup

from PIL import Image

 

# 当前项目路径

cur_path = os.getcwd() + '/'

 

class ZhiHuSpider(object):

    '''

    本类主要用于实现模拟知乎登陆并使用tesseract-ocr识别验证码

 

    Attribute:

        session: 建立会话

        url_signin: 登陆页面链接

        url_login: 登陆接口

        url_captcha: 验证码链接

        headers： 请求头部信息

        num: 识别验证码次数

    '''

 

    def __init__(self):

        self.session = requests.Session();

        self.url_signin = 'https://www.zhihu.com/#signin'

        self.url_login = 'https://www.zhihu.com/login/email'

        self.url_captcha = 'https://www.zhihu.com/captcha.gif?r=%d&type=login' % (time.time() * 1000)

        self.headers = {'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.101 Safari/537.36'}

        self.num = 1

 

    def get_captcha(self):

        '''

        获取并使用tesseract-ocr识别验证码

 

        Returns:

            返回验证码

        '''

        # 创建文件夹存放验证码

        if not os.path.exists(cur_path + 'captcha'):

            os.mkdir(cur_path + 'captcha')

 

        captcha_text = ''

        while True:

            # 下载验证码图片

            captcha = self.session.get(self.url_captcha, headers=self.headers).content

            captcha_path = cur_path + 'captcha/captcha.gif' # 验证码图片路径

            captcha_path_new = cur_path + 'captcha/captcha_new.gif' # 处理后的验证码图片路径

            with open(captcha_path, 'wb') as f:

                f.write(captcha)

 

            # 图片处理便于识别文字：彩色转灰度，灰度转二值，二值图像识别

            im = Image.open(captcha_path)

            w, h = im.size

            im = im.convert('L') # convert()用于不同模式图像之间的转换

            threshold = 100 # 图片降噪处理

            table = []

            for i in range(256):

                if i < threshold:

                    table.append(0)

                else:

                    table.append(1)

            im = im.point(table, '1')

            w_new, h_new = w * 2, h * 2

            im = im.resize((w_new, h_new), Image.ANTIALIAS) # 图片放大

            im.save(captcha_path_new)

 

            # 执行tesseract-ocr识别验证码

            captcha_text_path = cur_path + 'captcha/captcha_text' # 识别验证码后验证码文字的存放路径

            cmd = '/usr/bin/tesseract %s %s' % (captcha_path_new, captcha_text_path)

            os.system(cmd)

            time.sleep(2)

            with open('%s.txt' % captcha_text_path, 'r') as f:

                try:

                    captcha_text = f.read().strip()

                    print('第 %d 次识别的验证码为：%s' % (self.num, captcha_text))

                    regex = re.compile('^[0-9a-zA-Z]{4}$') # 正则表达式

                    if captcha_text and re.search(regex, captcha_text):

                        break;

                    else:

                        print('验证码无效！重新识别中...')

                        self.num += 1

                        # time.sleep(2) # 避免过于频繁的访问

                except Exception as e:

                    print('Exception:', e)

                    break;

        return captcha_text

 

    def login(self, username, password):

        '''

        登陆接口

 

        Args:

            username: 登陆账户

            password: 登陆密码

        Returns:

            返回登录结果list

        '''

        soup = BeautifulSoup(self.session.get(self.url_signin, headers=self.headers).content, 'html.parser')

        # 获取xsrf_token

        xsrf = soup.find('input', attrs={'name': '_xsrf'}).get('value')

        post_data = {

            '_xsrf': xsrf,

            'email': username,

            'password': password,

            'captcha': self.get_captcha()

        }

        login_ret = self.session.post(self.url_login, post_data, headers=self.headers).json()

        return login_ret

 

    def get_index_topic(self):

        '''

        获取首页第一条话题记录

        '''

        print('-'*50, '获取知乎首页第一条话题记录', '-'*50, sep="\n")

        soup = BeautifulSoup(self.session.get(self.url_signin, headers=self.headers).content, 'html.parser')

        item = soup.find('div', attrs={'class': 'Card TopstoryItem TopstoryItem--experimentFont18'})

        popover = item.find('div', attrs={'class': 'Feed-title'}).find('div', attrs={'class': 'Popover'}).find('div').get_text() # 话题

        print('来自话题：%s' % popover)

        title = item.find('div', attrs={'class': 'ContentItem AnswerItem'}).find('meta', attrs={'itemprop': 'name'}).get('content') # 标题

        print('title: %s' % title)

        content = item.find('div', attrs={'class': 'ContentItem AnswerItem'}).find('span', attrs={'class': 'RichText CopyrightRichText-richText'}).get_text() # 内容

        print('content: %s' % content)

 

if  __name__ == '__main__':

    zhihu = ZhiHuSpider()

    # 循环尝试登陆

    while True:

        ret = zhihu.login('知乎登陆邮箱', '知乎密码')

        if ret['r'] == 0:

            print('登陆成功! ')

            zhihu.get_index_topic()

            break

        else:

            print('登陆失败: %s' % ret['msg'])

 

运行效果图