Requests模块
一 Requests模块简介
#介绍:使用requests可以模拟浏览器的请求,比起之前用到的urllib,requests模块的api更加便捷(本质就是封装了urllib3) #注意:requests库发送请求将网页内容下载下来以后,并不会执行js代码,这需要我们自己分析目标站点然后发起新的request请求 #安装:pip3 install requests #各种请求方式:常用的就是requests.get()和requests.post() >>> import requests >>> r = requests.get('https://api.github.com/events') >>> r = requests.post('http://httpbin.org/post', data = {'key':'value'}) >>> r = requests.put('http://httpbin.org/put', data = {'key':'value'}) >>> r = requests.delete('http://httpbin.org/delete') >>> r = requests.head('http://httpbin.org/get') >>> r = requests.options('http://httpbin.org/get')
#建议在正式学习requests前,先熟悉下HTTP协议
https://www.cnblogs.com/liuqingzheng/p/10191056.html
官网链接:http://docs.python-requests.org/en/master/
二 基于GET请求
1、基本请求
import requests
response=requests.get('http://dig.chouti.com/')
print(response.text)
2、带参数的GET请求->params
import requests response=requests.get('https://www.baidu.com/s?wd=python&pn=1', headers={ 'User-Agent':'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/62.0.3202.75 Safari/537.36', }) print(response.text) # response.encoding=response.apparent_encoding with open('ptyhon.html','wb') as f: f.write(response.content)
#如果查询关键词是中文或者有其他特殊符号,则不得不进行url编码 from urllib.parse import urlencode wd='美女' encode_res=urlencode({'k':wd},encoding='utf-8') keyword=encode_res.split('=')[1] print(keyword) # 然后拼接成url url='https://www.baidu.com/s?wd=%s&pn=1' %keyword response=requests.get(url, headers={ 'User-Agent':'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/62.0.3202.75 Safari/537.36', }) with open('girl.html','wb') as f: f.write(response.content)
3、带参数的GET请求->headers
#通常我们在发送请求时都需要带上请求头,请求头是将自身伪装成浏览器的关键,常见的有用的请求头如下 Host Referer #大型网站通常都会根据该参数判断请求的来源 User-Agent #客户端 Cookie #Cookie信息虽然包含在请求头里,但requests模块有单独的参数来处理他,headers={}内就不要放它了
#添加headers(浏览器会识别请求头,不加可能会被拒绝访问,比如访问https://www.zhihu.com/explore) import requests response=requests.get('https://www.zhihu.com/explore') response.status_code #500 #自己定制headers headers={ 'User-Agent':'Mozilla/5.0 (Linux; Android 6.0; Nexus 5 Build/MRA58N) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/46.0.2490.76 Mobile Safari/537.36', } respone=requests.get('https://www.zhihu.com/explore', headers=headers) print(respone.status_code) #200
4、带参数的GET请求->cookies
import requests Cookies={ 'user_session':'rzNme4L6LTH7QSresq8w0BVYhTNt5GS-asNnkOe7_FZ2CjB6', } response=requests.get('https://github.com/settings/emails', cookies=Cookies) #github对请求头没有什么限制,我们无需定制user-agent,对于其他网站可能还需要定制 print('306334678@qq.com' in response.text) #True
三 基于POST请求
1 介绍
#GET请求 HTTP默认的请求方法就是GET * 没有请求体 * 数据必须在1K之内! * GET请求数据会暴露在浏览器的地址栏中 GET请求常用的操作: 1. 在浏览器的地址栏中直接给出URL,那么就一定是GET请求 2. 点击页面上的超链接也一定是GET请求 3. 提交表单时,表单默认使用GET请求,但可以设置为POST #POST请求 (1). 数据不会出现在地址栏中 (2). 数据的大小没有上限 (3). 有请求体 (4). 请求体中如果存在中文,会使用URL编码! #!!!requests.post()用法与requests.get()完全一致,特殊的是requests.post()有一个data参数,用来存放请求体数据
2、发送post请求,模拟浏览器的登录行为
#对于登录来说,应该输错用户名或密码然后分析抓包流程,用脑子想一想,输对了浏览器就跳转了,还分析个毛线,累死你也找不到包
''' 一 目标站点分析 浏览器输入https://github.com/login 然后输入错误的账号密码,抓包 发现登录行为是post提交到:https://github.com/session 而且请求头包含cookie 而且请求体包含: commit:Sign in utf8:✓ authenticity_token:lbI8IJCwGslZS8qJPnof5e7ZkCoSoMn6jmDTsL1r/m06NLyIbw7vCrpwrFAPzHMep3Tmf/TSJVoXWrvDZaVwxQ== login:egonlin password:123 二 流程分析 先GET:https://github.com/login拿到初始cookie与authenticity_token 返回POST:https://github.com/session, 带上初始cookie,带上请求体(authenticity_token,用户名,密码等) 最后拿到登录cookie ps:如果密码时密文形式,则可以先输错账号,输对密码,然后到浏览器中拿到加密后的密码,github的密码是明文 ''' import requests import re #第一次请求 r1=requests.get('https://github.com/login') r1_cookie=r1.cookies.get_dict() #拿到初始cookie(未被授权) authenticity_token=re.findall(r'name="authenticity_token".*?value="(.*?)"',r1.text)[0] #从页面中拿到CSRF TOKEN #第二次请求:带着初始cookie和TOKEN发送POST请求给登录页面,带上账号密码 data={ 'commit':'Sign in', 'utf8':'✓', 'authenticity_token':authenticity_token, 'login':'317828332@qq.com', 'password':'alex3714' } r2=requests.post('https://github.com/session', data=data, cookies=r1_cookie ) login_cookie=r2.cookies.get_dict() #第三次请求:以后的登录,拿着login_cookie就可以,比如访问一些个人配置 r3=requests.get('https://github.com/settings/emails', cookies=login_cookie) print('317828332@qq.com' in r3.text) #True
import requests import re session=requests.session() #第一次请求 r1=session.get('https://github.com/login') authenticity_token=re.findall(r'name="authenticity_token".*?value="(.*?)"',r1.text)[0] #从页面中拿到CSRF TOKEN #第二次请求 data={ 'commit':'Sign in', 'utf8':'✓', 'authenticity_token':authenticity_token, 'login':'317828332@qq.com', 'password':'alex3714' } r2=session.post('https://github.com/session', data=data, ) #第三次请求 r3=session.get('https://github.com/settings/emails') print('317828332@qq.com' in r3.text) #True
3、补充json
requests.post(url='xxxxxxxx', data={'xxx':'yyy'}) #没有指定请求头,#默认的请求头:application/x-www-form-urlencoed #如果我们自定义请求头是application/json,并且用data传值, 则服务端取不到值 requests.post(url='', data={'':1,}, headers={ 'content-type':'application/json' }) requests.post(url='', json={'':1,}, ) #默认的请求头:application/json
四 响应Response
1、response属性
import requests respone=requests.get('http://www.jianshu.com') # respone属性 print(respone.text) print(respone.content) print(respone.status_code) print(respone.headers) print(respone.cookies) print(respone.cookies.get_dict()) print(respone.cookies.items()) print(respone.url) print(respone.history) print(respone.encoding) #关闭:response.close() from contextlib import closing with closing(requests.get('xxx',stream=True)) as response: for line in response.iter_content(): pass
2、编码问题
#编码问题 import requests response=requests.get('http://www.autohome.com/news') # response.encoding='gbk' #汽车之家网站返回的页面内容为gb2312编码的,而requests的默认编码为ISO-8859-1,如果不设置成gbk则中文乱码 print(response.text)
3、获取二进制数据
import requests response=requests.get('https://timgsa.baidu.com/timg?image&quality=80&size=b9999_10000&sec=1509868306530&di=712e4ef3ab258b36e9f4b48e85a81c9d&imgtype=0&src=http%3A%2F%2Fc.hiphotos.baidu.com%2Fimage%2Fpic%2Fitem%2F11385343fbf2b211e1fb58a1c08065380dd78e0c.jpg') with open('a.jpg','wb') as f: f.write(response.content)
#stream参数:一点一点的取,比如下载视频时,如果视频100G,用response.content然后一下子写到文件中是不合理的 import requests response=requests.get('https://gss3.baidu.com/6LZ0ej3k1Qd3ote6lo7D0j9wehsv/tieba-smallvideo-transcode/1767502_56ec685f9c7ec542eeaf6eac93a65dc7_6fe25cd1347c_3.mp4', stream=True) with open('b.mp4','wb') as f: for line in response.iter_content(): f.write(line)
4、解析json
#解析json import requests response=requests.get('http://httpbin.org/get') import json res1=json.loads(response.text) #太麻烦 res2=response.json() #直接获取json数据 print(res1 == res2) #True
5、Redirection and History
import requests import re #第一次请求 r1=requests.get('https://github.com/login') r1_cookie=r1.cookies.get_dict() #拿到初始cookie(未被授权) authenticity_token=re.findall(r'name="authenticity_token".*?value="(.*?)"',r1.text)[0] #从页面中拿到CSRF TOKEN #第二次请求:带着初始cookie和TOKEN发送POST请求给登录页面,带上账号密码 data={ 'commit':'Sign in', 'utf8':'✓', 'authenticity_token':authenticity_token, 'login':'317828332@qq.com', 'password':'alex3714' } #测试一:没有指定allow_redirects=False,则响应头中出现Location就跳转到新页面,r2代表新页面的response r2=requests.post('https://github.com/session', data=data, cookies=r1_cookie ) print(r2.status_code) #200 print(r2.url) #看到的是跳转后的页面 print(r2.history) #看到的是跳转前的response print(r2.history[0].text) #看到的是跳转前的response.text #测试二:指定allow_redirects=False,则响应头中即便出现Location也不会跳转到新页面,r2代表的仍然是老页面的response r2=requests.post('https://github.com/session', data=data, cookies=r1_cookie, allow_redirects=False ) print(r2.status_code) #302 print(r2.url) #看到的是跳转前的页面https://github.com/session print(r2.history) #[]
五 高级用法
1、SSL Cert Verification
#证书验证(大部分网站都是https) import requests respone=requests.get('https://www.12306.cn') #如果是ssl请求,首先检查证书是否合法,不合法则报错,程序终端 #改进1:去掉报错,但是会报警告 import requests respone=requests.get('https://www.12306.cn',verify=False) #不验证证书,报警告,返回200 print(respone.status_code) #改进2:去掉报错,并且去掉警报信息 import requests from requests.packages import urllib3 urllib3.disable_warnings() #关闭警告 respone=requests.get('https://www.12306.cn',verify=False) print(respone.status_code) #改进3:加上证书 #很多网站都是https,但是不用证书也可以访问,大多数情况都是可以携带也可以不携带证书 #知乎\百度等都是可带可不带 #有硬性要求的,则必须带,比如对于定向的用户,拿到证书后才有权限访问某个特定网站 import requests respone=requests.get('https://www.12306.cn', cert=('/path/server.crt', '/path/key')) print(respone.status_code)
2、使用代理
#官网链接: http://docs.python-requests.org/en/master/user/advanced/#proxies #代理设置:先发送请求给代理,然后由代理帮忙发送(封ip是常见的事情) import requests proxies={ 'http':'http://egon:123@localhost:9743',#带用户名密码的代理,@符号前是用户名与密码 'http':'http://localhost:9743', 'https':'https://localhost:9743', } respone=requests.get('https://www.12306.cn', proxies=proxies) print(respone.status_code) #支持socks代理,安装:pip install requests[socks] import requests proxies = { 'http': 'socks5://user:pass@host:port', 'https': 'socks5://user:pass@host:port' } respone=requests.get('https://www.12306.cn', proxies=proxies) print(respone.status_code)
3、超时设置
#超时设置 #两种超时:float or tuple #timeout=0.1 #代表接收数据的超时时间 #timeout=(0.1,0.2)#0.1代表链接超时 0.2代表接收数据的超时时间 import requests respone=requests.get('https://www.baidu.com', timeout=0.0001)
4、 认证设置
#官网链接:http://docs.python-requests.org/en/master/user/authentication/ #认证设置:登陆网站是,弹出一个框,要求你输入用户名密码(与alter很类似),此时是无法获取html的 # 但本质原理是拼接成请求头发送 # r.headers['Authorization'] = _basic_auth_str(self.username, self.password) # 一般的网站都不用默认的加密方式,都是自己写 # 那么我们就需要按照网站的加密方式,自己写一个类似于_basic_auth_str的方法 # 得到加密字符串后添加到请求头 # r.headers['Authorization'] =func('.....') #看一看默认的加密方式吧,通常网站都不会用默认的加密设置 import requests from requests.auth import HTTPBasicAuth r=requests.get('xxx',auth=HTTPBasicAuth('user','password')) print(r.status_code) #HTTPBasicAuth可以简写为如下格式 import requests r=requests.get('xxx',auth=('user','password')) print(r.status_code)
5、异常处理
#异常处理 import requests from requests.exceptions import * #可以查看requests.exceptions获取异常类型 try: r=requests.get('http://www.baidu.com',timeout=0.00001) except ReadTimeout: print('===:') # except ConnectionError: #网络不通 # print('-----') # except Timeout: # print('aaaaa') except RequestException: print('Error')
6、上传文件
import requests files={'file':open('a.jpg','rb')} respone=requests.post('http://httpbin.org/post',files=files) print(respone.status_code)
六 案例
import requests import re import time def get_page(url): try: response=requests.get(url) if response.status_code==200: return response.text except Exception as e: print(e) def get_detail(index_page): urls=re.findall('class="categoryem".*?href="(.*?)"',index_page,re.S) # print(urls) for url in urls: yield 'https://www.pearvideo.com/'+url def pase_detail(detail_page): # print(detail_page) down_url=re.findall('srcUrl="(.*?)"',detail_page,re.S)[0] print(down_url) return down_url def get_movie(url): response=requests.get(url) with open('movie/%s.mp4'%str(time.time()),'wb') as f: f.write(response.content) print('下载成功') if __name__ == '__main__': index_page=get_page('https://www.pearvideo.com/category_loading.jsp?reqType=5&categoryId=8&start=24') urls=get_detail(index_page) for url in urls: print(url) detail_page=get_page(url) mp4_url=pase_detail(detail_page) get_movie(mp4_url)
import requests import re import time from concurrent.futures import ThreadPoolExecutor pool=ThreadPoolExecutor(50) def get_page(url): try: response=requests.get(url) if response.status_code==200: return response.text except Exception as e: print(e) def pase_index(index_page): index_page=index_page.result() urls=re.findall('class="categoryem".*?href="(.*?)"',index_page,re.S) # print(urls) for url in urls: next_url= 'https://www.pearvideo.com/'+url pool.submit(get_page, next_url).add_done_callback(pase_detail) def pase_detail(detail_page): detail_page=detail_page.result() # print(detail_page) down_url=re.findall('srcUrl="(.*?)"',detail_page,re.S)[0] pool.submit(get_movie, down_url) def get_movie(url): print(url) response=requests.get(url) with open('movie/%s.mp4'%str(time.time()),'wb') as f: f.write(response.content) print('下载成功') if __name__ == '__main__': for i in range(5): url='https://www.pearvideo.com/category_loading.jsp?reqType=5&categoryId=8&start=%s'%((i+1)*12) pool.submit(get_page, url).add_done_callback(pase_index)
import requests from bs4 import BeautifulSoup import os for i in range(1, 10): ret = requests.get(url='https://www.autohome.com.cn/news/%s/#liststart' % (i,)) ret.encoding = ret.apparent_encoding soup = BeautifulSoup(ret.text, 'lxml') div = soup.find(name='div', attrs={'id': 'auto-channel-lazyload-article'}) li_list = div.find_all(name='li') for li in li_list: h3 = li.find(name='h3') if not h3: continue p_text = li.find(name='p').text href = li.find(name='a').get('href') img = li.find(name='img').get('src') print(''' 新闻标题:%s 新闻简介:%s 新闻地址:%s 新闻图片:%s ''' % (h3.text, p_text, 'https:' + href, 'https:' + img)) ret_photo = requests.get(url='https:' + img) photo_name = img.rsplit('__', 1)[-1] if not os.path.exists('download'): os.mkdir('download') with open('download/' + photo_name, 'wb') as f: f.write(ret_photo.content)
import requests from bs4 import BeautifulSoup import time # 打开抽屉首页 ret = requests.get(url='https://dig.chouti.com/', headers={ 'user-agent': 'Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36', # 'accept-language': 'zh-CN,zh;q=0.9' } ) # print(ret.text) coo = ret.cookies.get_dict() print(coo) # 8613121758648 # woshiniba # 登录到抽屉 ret_login = requests.post(url='https://dig.chouti.com/login', headers={ 'user-agent': 'Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36' }, data={ 'phone': '8618953675221', 'password': 'lqz123', 'oneMonth': '1' }, cookies=coo ) print(ret_login.text) # print(ret_login.cookies.get_dict()) # https://dig.chouti.com/link/vote?linksId=21055766 # ret_post = requests.post(url='https://dig.chouti.com/link/vote?linksId=21055766', # headers={ # 'user-agent': 'Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36' # }, # cookies=coo # ) # print(ret_post.text) for i in range(2,3): ret_index = requests.get(url='https://dig.chouti.com/all/hot/recent/%s'%i, headers={ 'user-agent': 'Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36', } ) soup = BeautifulSoup(ret_index.text, 'html.parser') div = soup.find(name='div', attrs={'id': 'content-list'}) # print(div) item_list = div.find_all(name='div', attrs={'class': 'item'}) print(item_list) for item in item_list: part2_div = item.find(name='div', attrs={'class': 'part2'}) nid = part2_div.get('share-linkid') print(nid) time.sleep(0.5) ret_post = requests.post(url='https://dig.chouti.com/link/vote?linksId=%s' % nid, headers={ 'user-agent': 'Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36' }, cookies=coo ) print(ret_post.text) # 给文章评论 # ret_post = requests.post(url='https://dig.chouti.com/comments/create', # headers={ # 'user-agent': 'Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36' # }, # cookies=coo, # data={ # 'jid': 'cdu_53207078460', # 'linkId': '21061426', # 'isAssent': '', # 'content': '写的真好', # 'sortType':'score' # # } # )