Python requests模块基础使用方法实例及高级应用(自动登陆,抓取网页源码)实例详解

1、Python requests模块说明

requests是使用Apache2 licensed 许可证的HTTP库。

用python编写。

比urllib2模块更简洁。

Request支持HTTP连接保持和连接池，支持使用cookie保持会话，支持文件上传，支持自动响应内容的编码，支持国际化的URL和POST数据自动编码。

在python内置模块的基础上进行了高度的封装，从而使得python进行网络请求时，变得人性化，使用Requests可以轻而易举的完成浏览器可有的任何操作。

现代，国际化，友好。

requests会自动实现持久连接keep-alive

2、Python requests模块基础入门

1）导入模块

import requests

2）发送请求的简洁

示例代码：获取一个网页（个人github）

import requests
r = requests.get('https://github.com/Ranxf')    # 最基本的不带参数的get请求
r1 = requests.get(url='http://dict.baidu.com/s', params={'wd': 'python'})   # 带参数的get请求

我们还可以使用requests模块其它请求方法

1   requests.get(‘https://github.com/timeline.json')                                # GET请求

2   requests.post(“http://httpbin.org/post”)                                        # POST请求

3   requests.put(“http://httpbin.org/put”)                                          # PUT请求

4   requests.delete(“http://httpbin.org/delete”)                                    # DELETE请求

5   requests.head(“http://httpbin.org/get”)                                         # HEAD请求

6   requests.options(“http://httpbin.org/get” )                                     # OPTIONS请求

3）为url传递参数

>>> url_params = {'key':'value'}    #  字典传递参数，如果值为None的键不会被添加到url中
>>> r = requests.get('your url',params = url_params)
>>> print(r.url)

　　your url?key=value

4）响应的内容

r.encoding                       #获取当前的编码

r.encoding = 'utf-8'             #设置编码

r.text                           #以encoding解析返回内容。字符串方式的响应体，会自动根据响应头部的字符编码进行解码。

r.content                        #以字节形式（二进制）返回。字节方式的响应体，会自动为你解码 gzip 和 deflate 压缩。

r.headers                        #以字典对象存储服务器响应头，但是这个字典比较特殊，字典键不区分大小写，若键不存在则返回None

r.status_code                     #响应状态码

r.raw                             #返回原始响应体，也就是 urllib 的 response 对象，使用 r.raw.read()   

r.ok                              # 查看r.ok的布尔值便可以知道是否登陆成功

 #*特殊方法*#

r.json()                         #Requests中内置的JSON解码器，以json形式返回,前提返回的内容确保是json格式的，不然解析出错会抛异常

r.raise_for_status()             #失败请求(非200响应)抛出异常

post发送json请求：

import requests
import json

r = requests.post('https://api.github.com/some/endpoint', data=json.dumps({'some': 'data'}))

print(r.json())

5）定制头和cookie信息

header = {'user-agent': 'my-app/0.0.1''}
cookie = {'key':'value'}
 r = requests.get/post('your url',headers=header,cookies=cookie) 
data = {'some': 'data'}
headers = {'content-type': 'application/json',
      'User-Agent': 'Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:22.0) Gecko/20100101 Firefox/22.0'}

r = requests.post('https://api.github.com/some/endpoint', data=data, headers=headers)
print(r.text)

6）响应状态码

使用requests方法后，会返回一个response对象，其存储了服务器响应的内容，如上实例中已经提到的 r.text、r.status_code……

获取文本方式的响应体实例：当你访问 r.text 之时，会使用其响应的文本编码进行解码，并且你可以修改其编码让 r.text 使用自定义的编码进行解码。

r = requests.get('http://www.itwhy.org')
print(r.text, '\n{}\n'.format('*'*79), r.encoding)
r.encoding = 'GBK'
print(r.text, '\n{}\n'.format('*'*79), r.encoding)

示例代码：

import requests

r = requests.get('https://github.com/Ranxf')    # 最基本的不带参数的get请求
print(r.status_code)                # 获取返回状态
r1 = requests.get(url='http://dict.baidu.com/s', params={'wd': 'python'})   # 带参数的get请求
print(r1.url)
print(r1.text)    # 打印解码后的返回数据

运行结果：

/usr/bin/python3.5 /home/rxf/python3_1000/1000/python3_server/python3_requests/demo1.py

200

http://dict.baidu.com/s?wd=python

…………

Process finished with exit code 0

 r.status_code                      #如果不是200，可以使用 r.raise_for_status() 抛出异常

7）响应

r.headers                                  #返回字典类型,头信息

r.requests.headers                         #返回发送到服务器的头信息

r.cookies                                  #返回cookie

r.history                                  #返回重定向信息,当然可以在请求是加上allow_redirects = false 阻止重定向

8）超时

r = requests.get('url',timeout=1)      #设置秒数超时，仅对于连接有效

9)会话对象，能够跨请求保持某些参数

s = requests.Session()
s.auth = ('auth','passwd')
s.headers = {'key':'value'}
r = s.get('url')
r1 = s.get('url1') 

10）代理

proxies = {'http':'ip1','https':'ip2' }
requests.get('url',proxies=proxies)

汇总：

# HTTP请求类型
# get类型
r = requests.get('https://github.com/timeline.json')
# post类型
r = requests.post("http://m.ctrip.com/post")
# put类型
r = requests.put("http://m.ctrip.com/put")
# delete类型
r = requests.delete("http://m.ctrip.com/delete")
# head类型
r = requests.head("http://m.ctrip.com/head")
# options类型
r = requests.options("http://m.ctrip.com/get")

# 获取响应内容
print(r.content) #以字节的方式去显示，中文显示为字符
print(r.text) #以文本的方式去显示

#URL传递参数
payload = {'keyword': '香港', 'salecityid': '2'}
r = requests.get("http://m.ctrip.com/webapp/tourvisa/visa_list", params=payload) 
print（r.url） #示例为http://m.ctrip.com/webapp/tourvisa/visa_list?salecityid=2&keyword=香港

#获取/修改网页编码
r = requests.get('https://github.com/timeline.json')
print （r.encoding）


#json处理
r = requests.get('https://github.com/timeline.json')
print（r.json()） # 需要先import json  

# 定制请求头
url = 'http://m.ctrip.com'
headers = {'User-Agent' : 'Mozilla/5.0 (Linux; Android 4.2.1; en-us; Nexus 4 Build/JOP40D) AppleWebKit/535.19 (KHTML, like Gecko) Chrome/18.0.1025.166 Mobile Safari/535.19'}
r = requests.post(url, headers=headers)
print （r.request.headers)

#复杂post请求
url = 'http://m.ctrip.com'
payload = {'some': 'data'}
r = requests.post(url, data=json.dumps(payload)) #如果传递的payload是string而不是dict，需要先调用dumps方法格式化一下

# post多部分编码文件
url = 'http://m.ctrip.com'
files = {'file': open('report.xls', 'rb')}
r = requests.post(url, files=files)

# 响应状态码
r = requests.get('http://m.ctrip.com')
print(r.status_code)

# 响应头
r = requests.get('http://m.ctrip.com')
print (r.headers)
print (r.headers['Content-Type'])
print (r.headers.get('content-type')) #访问响应头部分内容的两种方式

# Cookies
url = 'http://example.com/some/cookie/setting/url'
r = requests.get(url)
r.cookies['example_cookie_name']  #读取cookies

url = 'http://m.ctrip.com/cookies'
cookies = dict(cookies_are='working')
r = requests.get(url, cookies=cookies) #发送cookies

#设置超时时间
r = requests.get('http://m.ctrip.com', timeout=0.001)

#设置访问代理
proxies = {
      "http": "http://10.10.1.10:3128",
      "https": "http://10.10.1.100:4444",
     }
r = requests.get('http://m.ctrip.com', proxies=proxies)


#如果代理需要用户名和密码，则需要这样：
proxies = {
  "http": "http://user:pass@10.10.1.10:3128/",
}

# HTTP请求类型
# get类型
r = requests.get('https://github.com/timeline.json')
# post类型
r = requests.post("http://m.ctrip.com/post")
# put类型
r = requests.put("http://m.ctrip.com/put")
# delete类型
r = requests.delete("http://m.ctrip.com/delete")
# head类型
r = requests.head("http://m.ctrip.com/head")
# options类型
r = requests.options("http://m.ctrip.com/get")

# 获取响应内容
print(r.content) #以字节的方式去显示，中文显示为字符
print(r.text) #以文本的方式去显示

#URL传递参数
payload = {'keyword': '香港', 'salecityid': '2'}
r = requests.get("http://m.ctrip.com/webapp/tourvisa/visa_list", params=payload) 
print（r.url） #示例为http://m.ctrip.com/webapp/tourvisa/visa_list?salecityid=2&keyword=香港

#获取/修改网页编码
r = requests.get('https://github.com/timeline.json')
print （r.encoding）


#json处理
r = requests.get('https://github.com/timeline.json')
print（r.json()） # 需要先import json  

# 定制请求头
url = 'http://m.ctrip.com'
headers = {'User-Agent' : 'Mozilla/5.0 (Linux; Android 4.2.1; en-us; Nexus 4 Build/JOP40D) AppleWebKit/535.19 (KHTML, like Gecko) Chrome/18.0.1025.166 Mobile Safari/535.19'}
r = requests.post(url, headers=headers)
print （r.request.headers)

#复杂post请求
url = 'http://m.ctrip.com'
payload = {'some': 'data'}
r = requests.post(url, data=json.dumps(payload)) #如果传递的payload是string而不是dict，需要先调用dumps方法格式化一下

# post多部分编码文件
url = 'http://m.ctrip.com'
files = {'file': open('report.xls', 'rb')}
r = requests.post(url, files=files)

# 响应状态码
r = requests.get('http://m.ctrip.com')
print(r.status_code)

# 响应头
r = requests.get('http://m.ctrip.com')
print (r.headers)
print (r.headers['Content-Type'])
print (r.headers.get('content-type')) #访问响应头部分内容的两种方式

# Cookies
url = 'http://example.com/some/cookie/setting/url'
r = requests.get(url)
r.cookies['example_cookie_name']  #读取cookies

url = 'http://m.ctrip.com/cookies'
cookies = dict(cookies_are='working')
r = requests.get(url, cookies=cookies) #发送cookies

#设置超时时间
r = requests.get('http://m.ctrip.com', timeout=0.001)

#设置访问代理
proxies = {
      "http": "http://10.10.1.10:3128",
      "https": "http://10.10.1.100:4444",
     }
r = requests.get('http://m.ctrip.com', proxies=proxies)


#如果代理需要用户名和密码，则需要这样：
proxies = {
  "http": "http://user:pass@10.10.1.10:3128/",
}

3、示例代码

GET请求

# 1、无参数实例

import requests

ret = requests.get('https://github.com/timeline.json')

print(ret.url)
print(ret.text)



# 2、有参数实例

import requests

payload = {'key1': 'value1', 'key2': 'value2'}
ret = requests.get("http://httpbin.org/get", params=payload)

print(ret.url)
print(ret.text)

POST请求

# 1、基本POST实例

import requests

payload = {'key1': 'value1', 'key2': 'value2'}
ret = requests.post("http://httpbin.org/post", data=payload)

print(ret.text)


# 2、发送请求头和数据实例

import requests
import json

url = 'https://api.github.com/some/endpoint'
payload = {'some': 'data'}
headers = {'content-type': 'application/json'}

ret = requests.post(url, data=json.dumps(payload), headers=headers)

print(ret.text)
print(ret.cookies)

请求参数

def request(method, url, **kwargs):

    """Constructs and sends a :class:`Request `.

    :param method: method for the new :class:`Request` object.

    :param url: URL for the new :class:`Request` object.

    :param params: (optional) Dictionary or bytes to be sent in the query string for the :class:`Request`.

    :param data: (optional) Dictionary, bytes, or file-like object to send in the body of the :class:`Request`.

    :param json: (optional) json data to send in the body of the :class:`Request`.

    :param headers: (optional) Dictionary of HTTP Headers to send with the :class:`Request`.

    :param cookies: (optional) Dict or CookieJar object to send with the :class:`Request`.

    :param files: (optional) Dictionary of ``'name': file-like-objects`` (or ``{'name': file-tuple}``) for multipart encoding upload.

        ``file-tuple`` can be a 2-tuple ``('filename', fileobj)``, 3-tuple ``('filename', fileobj, 'content_type')``

        or a 4-tuple ``('filename', fileobj, 'content_type', custom_headers)``, where ``'content-type'`` is a string

        defining the content type of the given file and ``custom_headers`` a dict-like object containing additional headers

        to add for the file.

    :param auth: (optional) Auth tuple to enable Basic/Digest/Custom HTTP Auth.

    :param timeout: (optional) How long to wait for the server to send data

        before giving up, as a float, or a :ref:`(connect timeout, read

        timeout) ` tuple.

    :type timeout: float or tuple

    :param allow_redirects: (optional) Boolean. Set to True if POST/PUT/DELETE redirect following is allowed.

    :type allow_redirects: bool

    :param proxies: (optional) Dictionary mapping protocol to the URL of the proxy.

    :param verify: (optional) whether the SSL cert will be verified. A CA_BUNDLE path can also be provided. Defaults to ``True``.

    :param stream: (optional) if ``False``, the response content will be immediately downloaded.

    :param cert: (optional) if String, path to ssl client cert file (.pem). If Tuple, ('cert', 'key') pair.

    :return: :class:`Response ` object

    :rtype: requests.Response

    Usage::

      >>> import requests

      >>> req = requests.request('GET', 'http://httpbin.org/get')

     

参数示例代码

def param_method_url():
  # requests.request(method='get', url='http://127.0.0.1:8000/test/')
  # requests.request(method='post', url='http://127.0.0.1:8000/test/')
  pass


def param_param():
  # - 可以是字典
  # - 可以是字符串
  # - 可以是字节（ascii编码以内）

  # requests.request(method='get',
  # url='http://127.0.0.1:8000/test/',
  # params={'k1': 'v1', 'k2': '水电费'})

  # requests.request(method='get',
  # url='http://127.0.0.1:8000/test/',
  # params="k1=v1&k2=水电费&k3=v3&k3=vv3")

  # requests.request(method='get',
  # url='http://127.0.0.1:8000/test/',
  # params=bytes("k1=v1&k2=k2&k3=v3&k3=vv3", encoding='utf8'))

  # 错误
  # requests.request(method='get',
  # url='http://127.0.0.1:8000/test/',
  # params=bytes("k1=v1&k2=水电费&k3=v3&k3=vv3", encoding='utf8'))
  pass


def param_data():
  # 可以是字典
  # 可以是字符串
  # 可以是字节
  # 可以是文件对象

  # requests.request(method='POST',
  # url='http://127.0.0.1:8000/test/',
  # data={'k1': 'v1', 'k2': '水电费'})

  # requests.request(method='POST',
  # url='http://127.0.0.1:8000/test/',
  # data="k1=v1; k2=v2; k3=v3; k3=v4"
  # )

  # requests.request(method='POST',
  # url='http://127.0.0.1:8000/test/',
  # data="k1=v1;k2=v2;k3=v3;k3=v4",
  # headers={'Content-Type': 'application/x-www-form-urlencoded'}
  # )

  # requests.request(method='POST',
  # url='http://127.0.0.1:8000/test/',
  # data=open('data_file.py', mode='r', encoding='utf-8'), # 文件内容是：k1=v1;k2=v2;k3=v3;k3=v4
  # headers={'Content-Type': 'application/x-www-form-urlencoded'}
  # )
  pass


def param_json():
  # 将json中对应的数据进行序列化成一个字符串，json.dumps(...)
  # 然后发送到服务器端的body中，并且Content-Type是 {'Content-Type': 'application/json'}
  requests.request(method='POST',
           url='http://127.0.0.1:8000/test/',
           json={'k1': 'v1', 'k2': '水电费'})


def param_headers():
  # 发送请求头到服务器端
  requests.request(method='POST',
           url='http://127.0.0.1:8000/test/',
           json={'k1': 'v1', 'k2': '水电费'},
           headers={'Content-Type': 'application/x-www-form-urlencoded'}
           )


def param_cookies():
  # 发送Cookie到服务器端
  requests.request(method='POST',
           url='http://127.0.0.1:8000/test/',
           data={'k1': 'v1', 'k2': 'v2'},
           cookies={'cook1': 'value1'},
           )
  # 也可以使用CookieJar（字典形式就是在此基础上封装）
  from http.cookiejar import CookieJar
  from http.cookiejar import Cookie

  obj = CookieJar()
  obj.set_cookie(Cookie(version=0, name='c1', value='v1', port=None, domain='', path='/', secure=False, expires=None,
             discard=True, comment=None, comment_url=None, rest={'HttpOnly': None}, rfc2109=False,
             port_specified=False, domain_specified=False, domain_initial_dot=False, path_specified=False)
          )
  requests.request(method='POST',
           url='http://127.0.0.1:8000/test/',
           data={'k1': 'v1', 'k2': 'v2'},
           cookies=obj)


def param_files():
  # 发送文件
  # file_dict = {
  # 'f1': open('readme', 'rb')
  # }
  # requests.request(method='POST',
  # url='http://127.0.0.1:8000/test/',
  # files=file_dict)

  # 发送文件，定制文件名
  # file_dict = {
  # 'f1': ('test.txt', open('readme', 'rb'))
  # }
  # requests.request(method='POST',
  # url='http://127.0.0.1:8000/test/',
  # files=file_dict)

  # 发送文件，定制文件名
  # file_dict = {
  # 'f1': ('test.txt', "hahsfaksfa9kasdjflaksdjf")
  # }
  # requests.request(method='POST',
  # url='http://127.0.0.1:8000/test/',
  # files=file_dict)

  # 发送文件，定制文件名
  # file_dict = {
  #   'f1': ('test.txt', "hahsfaksfa9kasdjflaksdjf", 'application/text', {'k1': '0'})
  # }
  # requests.request(method='POST',
  #         url='http://127.0.0.1:8000/test/',
  #         files=file_dict)

  pass


def param_auth():
  from requests.auth import HTTPBasicAuth, HTTPDigestAuth

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

  # ret = requests.get('http://192.168.1.1',
  # auth=HTTPBasicAuth('admin', 'admin'))
  # ret.encoding = 'gbk'
  # print(ret.text)

  # ret = requests.get('http://httpbin.org/digest-auth/auth/user/pass', auth=HTTPDigestAuth('user', 'pass'))
  # print(ret)
  #


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

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


def param_allow_redirects():
  ret = requests.get('http://127.0.0.1:8000/test/', allow_redirects=False)
  print(ret.text)


def param_proxies():
  # proxies = {
  # "http": "61.172.249.96:80",
  # "https": "http://61.185.219.126:3128",
  # }

  # proxies = {'http://10.20.1.128': 'http://10.10.1.10:5323'}

  # ret = requests.get("http://www.proxy360.cn/Proxy", proxies=proxies)
  # print(ret.headers)


  # from requests.auth import HTTPProxyAuth
  #
  # proxyDict = {
  # 'http': '77.75.105.165',
  # 'https': '77.75.105.165'
  # }
  # auth = HTTPProxyAuth('username', 'mypassword')
  #
  # r = requests.get("http://www.google.com", proxies=proxyDict, auth=auth)
  # print(r.text)

  pass


def param_stream():
  ret = requests.get('http://127.0.0.1:8000/test/', stream=True)
  print(ret.content)
  ret.close()

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


def requests_session():
  import requests

  session = requests.Session()

  ### 1、首先登陆任何页面，获取cookie

  i1 = session.get(url="http://dig.chouti.com/help/service")

  ### 2、用户登陆，携带上一次的cookie，后台对cookie中的 gpsd 进行授权
  i2 = session.post(
    url="http://dig.chouti.com/login",
    data={
      'phone': "8615131255089",
      'password': "xxxxxx",
      'oneMonth': ""
    }
  )

  i3 = session.post(
    url="http://dig.chouti.com/link/vote?linksId=8589623",
  )
  print(i3.text)

json请求：

#! /usr/bin/python3
import requests
import json


class url_request():
  def __init__(self):
    ''' init '''

if __name__ == '__main__':
  heard = {'Content-Type': 'application/json'}
  payload = {'CountryName': '中国',
        'ProvinceName': '四川省',
        'L1CityName': 'chengdu',
        'L2CityName': 'yibing',
        'TownName': '',
        'Longitude': '107.33393',
        'Latitude': '33.157131',
        'Language': 'CN'}
  r = requests.post("http://www.xxxxxx.com/CityLocation/json/LBSLocateCity", heards=heard, data=payload)
  data = r.json()
  if r.status_code!=200:
    print('LBSLocateCity API Error' + str(r.status_code))
  print(data['CityEntities'][0]['CityID']) # 打印返回json中的某个key的value
  print(data['ResponseStatus']['Ack'])
  print(json.dump(data, indent=4, sort_keys=True, ensure_ascii=False)) # 树形打印json，ensure_ascii必须设为False否则中文会显示为unicode

Xml请求：

#! /usr/bin/python3
import requests

class url_request():
  def __init__(self):
    """init"""

if __name__ == '__main__':
  heards = {'Content-type': 'text/xml'}
  XML = '<?xml version="1.0" encoding="utf-8"?><soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"><soap:Body><Request xmlns="http://tempuri.org/"><jme><JobClassFullName>WeChatJSTicket.JobWS.Job.JobRefreshTicket,WeChatJSTicket.JobWS</JobClassFullName><Action>RUN</Action><Param>1</Param><HostIP>127.0.0.1</HostIP><JobInfo>1</JobInfo><NeedParallel>false</NeedParallel></jme></Request></soap:Body></soap:Envelope>'
  url = 'http://jobws.push.mobile.xxxxxxxx.com/RefreshWeiXInTokenJob/RefreshService.asmx'
  r = requests.post(url=url, heards=heards, data=XML)
  data = r.text
  print(data)

状态异常处理

import requests

URL = 'http://ip.taobao.com/service/getIpInfo.php' # 淘宝IP地址库API
try:
  r = requests.get(URL, params={'ip': '8.8.8.8'}, timeout=1)
  r.raise_for_status() # 如果响应状态码不是 200，就主动抛出异常
except requests.RequestException as e:
  print(e)
else:
  result = r.json()
  print(type(result), result, sep='\n')

上传文件

使用request模块，也可以上传文件，文件的类型会自动进行处理：

import requests

url = 'http://127.0.0.1:8080/upload'
files = {'file': open('/home/rxf/test.jpg', 'rb')}
#files = {'file': ('report.jpg', open('/home/lyb/sjzl.mpg', 'rb'))}   #显式的设置文件名

r = requests.post(url, files=files)
print(r.text)

request更加方便的是，可以把字符串当作文件进行上传：

import requests

url = 'http://127.0.0.1:8080/upload'
files = {'file': ('test.txt', b'Hello Requests.')}   #必需显式的设置文件名

r = requests.post(url, files=files)
print(r.text)

身份验证

基本身份认证(HTTP Basic Auth)

import requests
from requests.auth import HTTPBasicAuth

r = requests.get('https://httpbin.org/hidden-basic-auth/user/passwd', auth=HTTPBasicAuth('user', 'passwd'))
# r = requests.get('https://httpbin.org/hidden-basic-auth/user/passwd', auth=('user', 'passwd'))  # 简写
print(r.json())

另一种非常流行的HTTP身份认证形式是摘要式身份认证，Requests对它的支持也是开箱即可用的:

requests.get(URL, auth=HTTPDigestAuth('user', 'pass')

Cookies与会话对象

如果某个响应中包含一些Cookie，你可以快速访问它们：

import requests

r = requests.get('http://www.google.com.hk/')
print(r.cookies['NID'])
print(tuple(r.cookies))

要想发送你的cookies到服务器，可以使用 cookies 参数：

import requests

url = 'http://httpbin.org/cookies'
cookies = {'testCookies_1': 'Hello_Python3', 'testCookies_2': 'Hello_Requests'}
# 在Cookie Version 0中规定空格、方括号、圆括号、等于号、逗号、双引号、斜杠、问号、@，冒号，分号等特殊符号都不能作为Cookie的内容。
r = requests.get(url, cookies=cookies)
print(r.json())

会话对象让你能够跨请求保持某些参数，最方便的是在同一个Session实例发出的所有请求之间保持cookies，且这些都是自动处理的，甚是方便。

下面就来一个真正的实例，如下是快盘签到脚本：

import requests

headers = {'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
      'Accept-Encoding': 'gzip, deflate, compress',
      'Accept-Language': 'en-us;q=0.5,en;q=0.3',
      'Cache-Control': 'max-age=0',
      'Connection': 'keep-alive',
      'User-Agent': 'Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:22.0) Gecko/20100101 Firefox/22.0'}

s = requests.Session()
s.headers.update(headers)
# s.auth = ('superuser', '123')
s.get('https://www.kuaipan.cn/account_login.htm')

_URL = 'http://www.kuaipan.cn/index.php'
s.post(_URL, params={'ac':'account', 'op':'login'},
    data={'username':'****@foxmail.com', 'userpwd':'********', 'isajax':'yes'})
r = s.get(_URL, params={'ac':'zone', 'op':'taskdetail'})
print(r.json())
s.get(_URL, params={'ac':'common', 'op':'usersign'})

requests模块抓取网页源码并保存到文件示例

这是一个基本的文件保存操作，但这里有几个值得注意的问题：

1.安装requests包，命令行输入pip install requests即可自动安装。很多人推荐使用requests，自带的urllib.request也可以抓取网页源码

2.open方法encoding参数设为utf-8，否则保存的文件会出现乱码。

3.如果直接在cmd中输出抓取的内容，会提示各种编码错误，所以保存到文件查看。

4.with open方法是更好的写法，可以自动操作完毕后释放资源

Python requests模块抽屉自动登录

#! /urs/bin/python3
import requests

'''requests模块抓取网页源码并保存到文件示例'''
html = requests.get("http://www.baidu.com")
with open('test.txt', 'w', encoding='utf-8') as f:
  f.write(html.text)

'''读取一个txt文件，每次读取一行，并保存到另一个txt文件中的示例'''
ff = open('testt.txt', 'w', encoding='utf-8')
with open('test.txt', encoding="utf-8") as f:
  for line in f:
    ff.write(line)
    ff.close()

因为在命令行中打印每次读取一行的数据，中文会出现编码错误，所以每次读取一行并保存到另一个文件，这样来测试读取是否正常。（注意open的时候制定encoding编码方式）

Python requests模块自动登陆实例：

#!/usr/bin/env python
# -*- coding:utf-8 -*-
import requests


# ############## 方式一 ##############
"""
# ## 1、首先登陆任何页面，获取cookie
i1 = requests.get(url="http://dig.chouti.com/help/service")
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': "8615131255089",
    'password': "xxooxxoo",
    '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=8589523",
  cookies={'gpsd': gpsd}
)

print(i3.text)
"""


# ############## 方式二 ##############
"""
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': "8615131255089",
    'password': "xxooxxoo",
    'oneMonth': ""
  }
)
i3 = session.post(
  url="http://dig.chouti.com/link/vote?linksId=8589523"
)
print(i3.text)

"""

Python requests模块github自动登录

#!/usr/bin/env python
# -*- coding:utf-8 -*-

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)



# ############## 方式二 ##############
# session = requests.Session()
# # 1. 访问登陆页面，获取 authenticity_token
# i1 = session.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 = session.post('https://github.com/session', data=form_data)
# c2 = i2.cookies.get_dict()
# c1.update(c2)
# i3 = session.get('https://github.com/settings/repositories')
#
# 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)

Python requests模块知乎自动登录

#!/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)

Python requests模块博客园自动登录

#!/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)

Python requests模块拉勾网自动登录

#!/usr/bin/env python
# -*- coding:utf-8 -*-

import requests


# 第一步：访问登陆页,拿到X_Anti_Forge_Token，X_Anti_Forge_Code
# 1、请求url:https://passport.lagou.com/login/login.html
# 2、请求方法:GET
# 3、请求头:
#  User-agent
r1 = requests.get('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.cookies.get_dict())
# 第二步：登陆
# 1、请求url:https://passport.lagou.com/login/login.json
# 2、请求方法:POST
# 3、请求头:
#  cookie
#  User-agent
#  Referer:https://passport.lagou.com/login/login.html
#  X-Anit-Forge-Code:53165984
#  X-Anit-Forge-Token:3b6a2f62-80f0-428b-8efb-ef72fc100d78
#  X-Requested-With:XMLHttpRequest
# 4、请求体：
# isValidate:true
# username:15131252215
# password:ab18d270d7126ea65915c50288c22c0d
# request_form_verifyCode:''
# submit:''
r2 = requests.post(
  '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',
    'Referer': 'https://passport.lagou.com/login/login.html',
    'X-Anit-Forge-Code': X_Anti_Forge_Code,
    'X-Anit-Forge-Token': X_Anti_Forge_Token,
    'X-Requested-With': 'XMLHttpRequest'
  },
  data={
    "isValidate": True,
    'username': '15131255089',
    'password': 'ab18d270d7126ea65915c50288c22c0d',
    'request_form_verifyCode': '',
    'submit': ''
  },
  cookies=r1.cookies.get_dict()
)
print(r2.text)

更多关于Python requests模块基础使用方法请查看下面的相关链接