知乎改版api接口之scrapy自动登陆

最近使用scrapy模拟登陆知乎，发现所有接口都发生变化了，包括验证码也发生了很大变化，通过抓包分析，记录下改版后的知乎模拟登陆,废话不多说，直接上代码，亲测有效

# -*- coding: utf-8 -*-
from PIL import Image
from scrapy.exceptions import CloseSpider
import scrapy
import json
import base64

class ZhihuSpider(scrapy.Spider):
    name = 'zhihu'
    allowed_domains = ['www.zhihu.com']
    start_urls = ['http://www.zhihu.com/']
    handle_httpstatus_list = [401, 403]
    client_id = 'c3cef7c66a1843f8b3a9e6a1e3160e20'    #固定不变
    signature = 'b858d0c8b1f2e86c6cb0d93d4055963bcf1121ec'    #抓包获取
    timestamp = '1519567594106'       #抓包获取
    headers = {
        "HOST": "www.zhihu.com",
        "Referer": "https://www.zhihu.com/signup?next=%2F",
        "User-Agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.132 Safari/537.36Name",
        "authorization": "oauth c3cef7c66a1843f8b3a9e6a1e3160e20",
    }

    def parse(self, response):
        pass

    def start_requests(self):
        '''
        获取登陆页面，set_cookie
        :return:
        '''
        return [scrapy.Request(url='https://www.zhihu.com/signup?next=%2F',
                               headers=self.headers,
                               method="GET",
                               meta={'cookiejar':1},
                               callback=self.post_captchareq,
                               dont_filter=True,
                               )]

    def post_captchareq(self, response):
        '''
        发送获取验证码请求
        :param response:
        :return:
        '''
        return [scrapy.Request(
            url='https://www.zhihu.com/api/v3/oauth/captcha?lang=en',
            headers=self.headers,
            meta={'cookiejar': response.meta['cookiejar']},
            dont_filter=True,
            callback=self.deal_captchareq,
        )]

    def deal_captchareq(self, response):
        '''
        判断是否需要验证码
        :param response:
        :return:
        '''
        json_res = json.loads(response.text)
        post_data = {
            "client_id": self.client_id,
            "grant_type":"password",
            "timestamp": self.timestamp,
            "source": "com.zhihu.web",
            "signature": self.signature,
            "username": '+86你的手机号码',
            "password":'密码',
            "captcha": '',
            "lang":"en",
            "ref_source":"homepage",
            "utm_source":""
        }
        if json_res.get("show_captcha", None):
            return [
                scrapy.Request(
                    url='https://www.zhihu.com/api/v3/oauth/captcha?lang=en',
                    headers=self.headers,
                    method='PUT',
                    meta={'cookiejar': response.meta['cookiejar'],
                            'post_data':post_data},
                    callback=self.get_captchaimg
                )
            ]
        return [
            scrapy.FormRequest(
                url="https://www.zhihu.com/api/v3/oauth/sign_in",
                formdata=post_data,
                method="POST",
                headers=self.headers,
                meta={'cookiejar': response.meta['cookiejar']},
                callback=self.check_login,
                dont_filter=True,
            )
        ]

    def get_captchaimg(self, response):
        '''
        获取验证码图片流数据,手动输入验证码
        :param response:
        :return:
        '''
        post_data = response.meta['post_data']
        try:
            json_img = json.loads(response.text)
            bs64_img = json_img["img_base64"]
            bs64_img = bs64_img.encode('utf-8')
            img_steam = base64.b64decode(bs64_img)
            with open("zhihucaptcha.jpg", 'wb') as f:
                f.write(img_steam)
            img = Image.open("zhihucaptcha.jpg")
            img.show()
            input_captcha = input("请输入图中验证码：").strip()
            post_data['captcha'] = input_captcha
            img.close()
            post_code = {
                "input_text":input_captcha,
            }
            return [
                scrapy.FormRequest(
                    url="https://www.zhihu.com/api/v3/oauth/captcha?lang=en",
                    formdata=post_code,
                    headers=self.headers,
                    method='POST',
                    meta={'cookiejar': response.meta['cookiejar'],
                          'post_data':post_data},
                    callback=self.post_captcha,
                    dont_filter=True,
                )
            ]
        except Exception as e:
            raise CloseSpider('获取验证码发生错误:{error}'.format(error=e))

    def post_captcha(self, response):
        '''
        发送用户认证信息登陆
        :param response:
        :return:
        '''
        post_data = response.meta.get('post_data')
        if json.loads(response.text).get('success'):
            return [
                scrapy.FormRequest(
                    url="https://www.zhihu.com/api/v3/oauth/sign_in",
                    formdata=post_data,
                    headers=self.headers,
                    method='POST',
                    meta={'cookiejar': response.meta['cookiejar']},
                    callback=self.check_login,
                    dont_filter=True,
                )
            ]
        else:
            raise CloseSpider('验证码不正确')

    def check_login(self, response):
        #验证是否登陆成功
        print('==============>',response.text)
        print(response.status)
        if response.status == 201:
            self.logger.info("登陆成功!")
        else:
            raise CloseSpider('登陆信息有误！')　　

其中，其它参数如client_id, oauth等都是固定的，signature与timestamp是随着时间戳变化的，它是用于验证合法用户的token,实质也是一段客户端的js运行生成的，这里为了方便，直接通过抓包获取某个固定时间戳对应的signature

先在pc端输入错误账户信息，抓包获取timestamp与signature，替换对应的即可