requests和bs4

requests模块，仿造浏览器发送Http请求
bs4主要对html或xml格式字符串解析成对象，使用find/find_all查找 text/attrs

爬取汽车之家

爬取汽车之家的资讯信息，它没有做什么防爬策略，直接request爬取就可以了
    但是需要注意的是response返回的gbk编码，需要转码

import requests
from bs4 import BeautifulSoup

response = requests.get("https://www.autohome.com.cn/news/")
response.encoding = 'gbk'

soup = BeautifulSoup(response.text,'html.parser')

div = soup.find(name='div',attrs={'id':'auto-channel-lazyload-article'})

li_list = div.find_all(name='li')

for li in li_list:

    title = li.find(name='h3')
    if not title:
        continue
    p = li.find(name='p')
    a = li.find(name='a')

    print(title.text)
    print(a.attrs.get('href'))
    print(p.text)

    img = li.find(name='img')
    src = img.get('src')
    src = "https:" + src
    print(src)

    # 再次发起请求，下载图片
    file_name = src.rsplit('/',maxsplit=1)[1]
    ret = requests.get(src)
    with open(file_name,'wb') as f:
        f.write(ret.content)

爬取抽屉新热榜

获取抽屉新闻，需要携带请求头user-Agent
    对于登录，请求头需要携带登录前的cookie去做授权，加上user-Agent
    请求体        
        'phone':'8613121758648',
        'password':'woshiniba',
        'oneMonth':1
    登录成功后，携带授权cookie和user-agent，就可以进行点赞的相关操作了

""""""

# ################################### 示例一：爬取数据（携带请起头） ###################################
"""
import requests
from bs4 import BeautifulSoup

r1 = 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/63.0.3239.132 Safari/537.36'
    }
)

soup = BeautifulSoup(r1.text,'html.parser')

# 标签对象
content_list = soup.find(name='div',id='content-list')
# print(content_list)
# [标签对象,标签对象]
item_list = content_list.find_all(name='div',attrs={'class':'item'})
for item in item_list:
    a = item.find(name='a',attrs={'class':'show-content color-chag'})
    print(a.text.strip())
    # print(a.text)
"""
# ################################### 示例二：点赞 ###################################
"""
import requests
# 1. 查看首页
r1 = 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/63.0.3239.132 Safari/537.36'
    }
)

# 2. 提交用户名和密码
r2 = 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/63.0.3239.132 Safari/537.36'
    },
    data={
        'phone':'8613121758648',
        'password':'woshiniba',
        'oneMonth':1
    },
    cookies=r1.cookies.get_dict()
)

# 3. 点赞
r3 = requests.post(
    url='https://dig.chouti.com/link/vote?linksId=20435396',
    headers={
        'user-agent':'Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.132 Safari/537.36'
    },
    cookies=r1.cookies.get_dict()
)
print(r3.text)
"""

爬取GitHub

get访问登录页面：
        需要去HTML中找隐藏的Input标签获取csrf token
        获取cookie
    post登录
        请求体携带csrf token值和用户名密码等信息，进行登录验证
    其他的操作，携带cookie就可以了

""""""
# ################################### 示例三：自动登录GitHub ###################################
# 1. GET，访问登录页面
"""
- 去HTML中找隐藏的Input标签获取csrf token
- 获取cookie
"""

# 2. POST，用户名和密码
"""
- 发送数据：
    - csrf
    - 用户名
    - 密码
- 携带cookie
"""

# 3. GET,访问https://github.com/settings/emails
"""
- 携带 cookie
"""

import requests
from bs4 import BeautifulSoup

# ############## 方式一 ##############
#
# # 1. 访问登陆页面，获取 authenticity_token
# i1 = requests.get('https://github.com/login')
# soup1 = BeautifulSoup(i1.text, features='lxml')
# tag = soup1.find(name='input', attrs={'name': 'authenticity_token'})
# authenticity_token = tag.get('value')
# c1 = i1.cookies.get_dict()
# i1.close()
#
# # 1. 携带authenticity_token和用户名密码等信息，发送用户验证
# form_data = {
# "authenticity_token": authenticity_token,
#     "utf8": "",
#     "commit": "Sign in",
#     "login": "wupeiqi@live.com",
#     'password': 'xxoo'
# }
#
# i2 = requests.post('https://github.com/session', data=form_data, cookies=c1)
# c2 = i2.cookies.get_dict()
# c1.update(c2)
# i3 = requests.get('https://github.com/settings/repositories', cookies=c1)
#
# soup3 = BeautifulSoup(i3.text, features='lxml')
# list_group = soup3.find(name='div', class_='listgroup')
#
# from bs4.element import Tag
#
# for child in list_group.children:
#     if isinstance(child, Tag):
#         project_tag = child.find(name='a', class_='mr-1')
#         size_tag = child.find(name='small')
#         temp = "项目:%s(%s); 项目路径:%s" % (project_tag.get('href'), size_tag.string, project_tag.string, )
#         print(temp)

爬取拉勾网

get访问登录页面，请求需要携带user-agent
    
    post请求的请求头，除了加上User-Agent，还要加上referer上一次访问地址即登录url，还有
    两个特殊的请求头，它写在访问的登录页面的js中，需要正则匹配获取，
    
    请求体需要携带用户相关信息，这里还要注意这里密码是密文的

import re
import requests

r1 = requests.get(
    url='https://passport.lagou.com/login/login.html',
    headers={
        'User-Agent': 'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.132 Safari/537.36',
    }
)
X_Anti_Forge_Token = re.findall("X_Anti_Forge_Token = '(.*?)'", r1.text, re.S)[0]
X_Anti_Forge_Code = re.findall("X_Anti_Forge_Code = '(.*?)'", r1.text, re.S)[0]
# print(X_Anti_Forge_Token, X_Anti_Forge_Code)
# print(r1.text)
#
r2 = requests.post(
    url='https://passport.lagou.com/login/login.json',
    headers={
        'User-Agent': 'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.132 Safari/537.36',
        'X-Anit-Forge-Code':X_Anti_Forge_Code,
        'X-Anit-Forge-Token':X_Anti_Forge_Token,
        'Referer': 'https://passport.lagou.com/login/login.html', # 上一次请求地址是什么？
    },
    data={
        "isValidate": True,
        'username': '15131255089',
        'password': 'ab18d270d7126ea65915c50288c22c0d',
        'request_form_verifyCode': '',
        'submit': ''
    },
    cookies=r1.cookies.get_dict()
)
print(r2.text)

这防爬套路总结：
    post登录获取cookie，以后携带cookie或者get获取未授权cookie，post登录携带这个cookie去授权，以后携带cookie
    
    特殊请求头，去以前的请求信息里找

requests常用参数

　　url，headers，cookies，data，json，params，proxies代理

import requests

"""
# 1. 方法
    requests.get
    requests.post
    requests.put
    requests.delete
    ...
    requests.request(method='POST')
"""
# 2. 参数
"""
    2.1  url
    2.2  headers
    2.3  cookies
    2.4  params
    2.5  data，传请求体

            requests.post(
                ...,
                data={'user':'alex','pwd':'123'}
            )

            GET /index http1.1\r\nhost:c1.com\r\n\r\nuser=alex&pwd=123

    2.6  json，传请求体
            requests.post(
                ...,
                json={'user':'alex','pwd':'123'}
            )

            GET /index http1.1\r\nhost:c1.com\r\nContent-Type:application/json\r\n\r\n{"user":"alex","pwd":123}
    2.7 代理 proxies
        # 无验证
            proxie_dict = {
                "http": "61.172.249.96:80",
                "https": "http://61.185.219.126:3128",
            }
            ret = requests.get("https://www.proxy360.cn/Proxy", proxies=proxie_dict)

        # 验证代理
            from requests.auth import HTTPProxyAuth

            proxyDict = {
                'http': '77.75.105.165',
                'https': '77.75.106.165'
            }
            auth = HTTPProxyAuth('用户名', '密码')

            r = requests.get("http://www.google.com",data={'xxx':'ffff'} proxies=proxyDict, auth=auth)
            print(r.text)
    -----------------------------------------------------------------------------------------
    2.8 文件上传 files
        # 发送文件
            file_dict = {
                'f1': open('xxxx.log', 'rb')
            }
            requests.request(
                method='POST',
                url='http://127.0.0.1:8000/test/',
                files=file_dict
            )

    2.9 认证 auth

        内部：
            用户名和密码，用户和密码加密，放在请求头中传给后台。

                - "用户:密码"
                - base64("用户:密码")
                - "Basic base64("用户|密码")"
                - 请求头：
                    Authorization： "basic base64("用户|密码")"

        from requests.auth import HTTPBasicAuth, HTTPDigestAuth

        ret = requests.get('https://api.github.com/user', auth=HTTPBasicAuth('wupeiqi', 'sdfasdfasdf'))
        print(ret.text)

    2.10 超时 timeout
        # ret = requests.get('http://google.com/', timeout=1)
        # print(ret)

        # ret = requests.get('http://google.com/', timeout=(5, 1))
        # print(ret)

    2.11 允许重定向  allow_redirects
        ret = requests.get('http://127.0.0.1:8000/test/', allow_redirects=False)
        print(ret.text)

    2.12 大文件下载 stream
        from contextlib import closing
        with closing(requests.get('http://httpbin.org/get', stream=True)) as r1:
        # 在此处理响应。
        for i in r1.iter_content():
            print(i)

    2.13 证书 cert
        - 百度、腾讯 => 不用携带证书（系统帮你做了）
        - 自定义证书
            requests.get('http://127.0.0.1:8000/test/', cert="xxxx/xxx/xxx.pem")
            requests.get('http://127.0.0.1:8000/test/', cert=("xxxx/xxx/xxx.pem","xxx.xxx.xx.key"))
    2.14 确认 verify =False
"""

requests.get('http://127.0.0.1:8000/test/', cert="xxxx/xxx/xxx.pem")