03:requests与BeautifulSoup结合爬取网页数据应用
1.1 爬虫相关模块命令回顾
1、requests模块
1、 pip install requests
2、 response = requests.get('http://www.baidu.com/ ') #获取指定url的网页内容
3、 response.text #获取文本文件
4、 response.content #获取字节类型
5、 response.encoding = ‘utf-8’ #指定获取的网页内容用utf-8编码
response.encoding = response.apparent_encoding #下载的页面是什么编码就用什么编码格式
6、 response.cookies #拿到cookies
response.cookies.get_dict() #拿到cookie字典样式
2、beautisoup模块
1、 pip install beautifulsoup4
2、 把文本转成对象
1)html.parser 是python内置模块无需安装
soup = BeautiSoup(response.text,parser='html.parser')
2)lxml是第三方库,但是性能好(生产用这个
soup = BeautifulSoup(response.text,features='lxml')
3、 .find()用法:返回的是对象
1)从爬取的内容找到id="auto-channel-lazyload-article" 中div的内容
target = soup.find(id="auto-channel-lazyload-article")
2) 从爬取的内容中找到一个div,并且这个div有一个属性是id=’i1’
target = soup.find('div',id='i1')
4、 .find_all()用法:返回的是对象列表
1) 从以后取的target对象中找到所有li标签
li_list = target.find_all('li')
5、 从.find()获取的对象中找到想要的属性
a.attrs.get('href') #获取所有a标签的所有href属性(a标签url路径)
a.find('h3').text #找到a标签中的所有h3标签,的内容
img_url = a.find('img').attrs.get('src') #从a标签中找到img标签所有src属性(图片url路径)
1.2 爬取需要登录和不需要登录页面内容的方法
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import requests from bs4 import BeautifulSoup response = requests.get( url='http://www.autohome.com.cn/news/' ) response.encoding = response.apparent_encoding #下载的页面是什么编码就用什么编码格式 #1 把文本转成对象, #soup = BeautifulSoup(response.text,features='lxml') #lxml是第三方库,但是性能好(生产用这个) soup = BeautifulSoup(response.text,features='html.parser') # html.parser 是python内置模块无需安装 #2 从爬取的内容找到id="auto-channel-lazyload-article" 中div的内容 target = soup.find(id="auto-channel-lazyload-article") #3.1 找到所有li标签 .find()是找到第一个 #3.2 也可以这样用: .find('div',id='i1') 可以使用这种组合查找的方法 #3.3 .find()找到的是对象,.find_all() 获取的是列表 li_list = target.find_all('li') for i in li_list: a = i.find('a') if a: print(a.attrs.get('href')) #获取所有a标签的url路径 # a.find('h3') 获取的是对象, 加上 .text才是获取文本 txt = a.find('h3').text #从a标签中找到所有h3标签的值 print(txt,type(txt)) img_url = a.find('img').attrs.get('src')#从a标签中找到img标签所有src属性(图片url路径) import uuid file_name = str(uuid.uuid4()) + '.jpg' if img_url.startswith('//www2'): #由于获取的图片url做了处理,所以才这样处理 img_url2 = img_url.replace('//www2','http://www3') img_response = requests.get(url=img_url2) with open(file_name,'wb') as f: f.write(img_response.content) #把图片写到本地
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import requests #1 登录抽屉网站的用户名和密码放到字典里 post_dict = { "phone":'86185387525', 'password':'74810', 'oneMonth':1 } #2 将密码字典以post方式提交到抽屉的登录界面 response = requests.post( url = 'http://dig.chouti.com/login', data=post_dict ) #3下面就是成功登录抽屉的返回值 print(response.text) # {"result":{"code":"9999", "message":"", "data":{"complateReg":"0","destJid":"cdu_49844923242"}}} #4 下面是打印成功登录抽屉后返回的的cookie字典 cookie_dict = response.cookies.get_dict() print(cookie_dict) #{'JSESSIONID': 'aaaVizwwcod_L5QcwwR9v', 'puid': 'd332ef55361217e544b91f081090ad5e', # 'route': '37316285ff8286c7a96cd0b03d38e13b', 'gpsd': 'f8b07e259141ae5a11d930334fbfb609'} #5 当我们每次需要访问抽屉登录后才能看的信息时,就可以在url中添加登录成返回的cookie字典 response=requests.get( url='http://dig.chouti.com/profile', cookies = cookie_dict )
1.3 使用爬虫登录案例总结
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#!/usr/bin/env python # -*- coding:utf-8 -*- import requests # ## 1、首先登陆任何页面,获取cookie i1 = requests.get(url="http://dig.chouti.com/") i1_cookies = i1.cookies.get_dict() # ## 2、用户登陆,携带上一次的cookie,后台对cookie中的 gpsd 进行授权 i2 = requests.post( url="http://dig.chouti.com/login", data={ 'phone': "8618538752511", 'password': "7481079xl", 'oneMonth': "" }, cookies=i1_cookies ) # ## 3、点赞(只需要携带已经被授权的gpsd即可) gpsd = i1_cookies['gpsd'] i3 = requests.post( url="http://dig.chouti.com/link/vote?linksId=15074576", cookies={'gpsd': gpsd} ) print(i3.text)
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import requests session = requests.Session() i1 = session.get(url="http://dig.chouti.com/help/service") i2 = session.post( url="http://dig.chouti.com/login", data={ 'phone': "8618538752511", 'password': "7481079xl", 'oneMonth': "" }, ) i3 = session.post( url="http://dig.chouti.com/link/vote?linksId=15074576" ) print(i3.text)
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import requests from bs4 import BeautifulSoup # 第一步:获取csrf # 1.1 获取login页面 r1 = requests.get(url='https://github.com/login') # 1.2 接文本文件解析成对象 b1 = BeautifulSoup(r1.text,'html.parser') # 1.3 找到csrf_token标签 tag = b1.find(name='input',attrs={'name':'authenticity_token'}) #1.4 获取csrf_token的值 # tag.get('value')等价于 tag.attrs.get('values') token = tag.get('value') # 获取csrf_token的值 #1.5 获取第一次发送get请求返回的cookies字典 r1_cookie = r1.cookies.get_dict() #获取第一次发get请求返回的cookie print('第一次',r1_cookie) # 第二步:发送post请求,携带用户名 密码,和第一次get请求返回的cookie,后台进行授权 #2.1 携带:csrf_token,cookies,用户名,密码 发送post请求登录 # requests.post() 等价于 requests.request('post',) r2 = requests.post( url='https://github.com/session', data={ #这里data字典必须和实际登录的格式相同 'commit':'Sign in', 'utf8':'✓', 'authenticity_token':token, 'login':'1532363461@qq.com', 'password':'7481079xl', }, cookies = r1_cookie, ) #2.2 获取第二次返回的cookies字典 r2_cookie = r2.cookies.get_dict() print('第二次',r2_cookie) #2.3 将两次获取的cookie字典整合成一个:没有重合就用r1_cookie,有重合的就用r2_cookie更新这个字典 r1_cookie.update(r2_cookie) # 第三步:访问个人页面,携带cookie r3 = requests.get( url='https://github.com/settings/profile', cookies = r1_cookie, # 获取数据时携带登录成功的cookie ) print(r3.text)
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#!/usr/bin/env python # -*- coding:utf-8 -*- import time import requests from bs4 import BeautifulSoup session = requests.Session() i1 = session.get( url='https://www.zhihu.com/#signin', headers={ 'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2840.98 Safari/537.36', } ) soup1 = BeautifulSoup(i1.text, 'lxml') xsrf_tag = soup1.find(name='input', attrs={'name': '_xsrf'}) xsrf = xsrf_tag.get('value') current_time = time.time() i2 = session.get( url='https://www.zhihu.com/captcha.gif', params={'r': current_time, 'type': 'login'}, headers={ 'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2840.98 Safari/537.36', }) with open('zhihu.gif', 'wb') as f: f.write(i2.content) captcha = input('请打开zhihu.gif文件,查看并输入验证码:') form_data = { "_xsrf": xsrf, 'password': 'xxooxxoo', "captcha": 'captcha', 'email': '424662508@qq.com' } i3 = session.post( url='https://www.zhihu.com/login/email', data=form_data, headers={ 'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2840.98 Safari/537.36', } ) i4 = session.get( url='https://www.zhihu.com/settings/profile', headers={ 'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2840.98 Safari/537.36', } ) soup4 = BeautifulSoup(i4.text, 'lxml') tag = soup4.find(id='rename-section') nick_name = tag.find('span',class_='name').string print(nick_name)
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#!/usr/bin/env python # -*- coding:utf-8 -*- import re import json import base64 import rsa import requests def js_encrypt(text): b64der = 'MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCp0wHYbg/NOPO3nzMD3dndwS0MccuMeXCHgVlGOoYyFwLdS24Im2e7YyhB0wrUsyYf0/nhzCzBK8ZC9eCWqd0aHbdgOQT6CuFQBMjbyGYvlVYU2ZP7kG9Ft6YV6oc9ambuO7nPZh+bvXH0zDKfi02prknrScAKC0XhadTHT3Al0QIDAQAB' der = base64.standard_b64decode(b64der) pk = rsa.PublicKey.load_pkcs1_openssl_der(der) v1 = rsa.encrypt(bytes(text, 'utf8'), pk) value = base64.encodebytes(v1).replace(b'\n', b'') value = value.decode('utf8') return value session = requests.Session() i1 = session.get('https://passport.cnblogs.com/user/signin') rep = re.compile("'VerificationToken': '(.*)'") v = re.search(rep, i1.text) verification_token = v.group(1) form_data = { 'input1': js_encrypt('wptawy'), 'input2': js_encrypt('asdfasdf'), 'remember': False } i2 = session.post(url='https://passport.cnblogs.com/user/signin', data=json.dumps(form_data), headers={ 'Content-Type': 'application/json; charset=UTF-8', 'X-Requested-With': 'XMLHttpRequest', 'VerificationToken': verification_token} ) i3 = session.get(url='https://i.cnblogs.com/EditDiary.aspx') print(i3.text)
作者:学无止境
出处:https://www.cnblogs.com/xiaonq
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