python requests模块
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
官方文档：http://cn.python-requests.org/zh_CN/latest/
安装：pip3 install requests
requests模块的各种请求方式
源码构成如下
image
以上方法均是在此方法的基础上构建
requests.request(method, url, ``*``*``kwargs)
其中最常用的请求方式就是post和get请求，泵智商，post和get就是封装了request请求的请求方式
>>> r ``= requests.get(``'https://api.github.com/events'``)
相当于requests,request(method``=``'get'``, ``'https://api.github.com/events'``)
>>> r ``= requests.post(``'http://httpbin.org/post'``, data ``= {``'key'``:``'value'``})
相当于requests,request(method``=``'post'``, ``'https://api.github.com/events'``, data ``= {``'key'``:``'value'``})
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requests,request方法详解
request（）源码
def request(method, url, ``*``*``kwargs):
"""Constructs and sends a :class:Request <Request>.
:param method: method for the new :class:Requestobject.
:param url: URL for the new :class:Requestobject.
:param params: (optional) Dictionary or bytes to be sent in the query string for the :class:Request.
:param data: (optional) Dictionary or list of tuples ``[(key, value)]`` (will be form-encoded), 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 many seconds to wait for the server to send data
before giving up, as a float, or a :ref:(connect timeout, read`
timeout) <timeouts> tuple.`
:type timeout: float or tuple
:param allow_redirects: (optional) Boolean. Enable/disable GET/OPTIONS/POST/PUT/PATCH/DELETE/HEAD redirection. Defaults to ``True``.
:type allow_redirects: bool
:param proxies: (optional) Dictionary mapping protocol to the URL of the proxy.
:param verify: (optional) Either a boolean, in which case it controls whether we verify
the server's TLS certificate, or a string, in which case it must be a path
to a CA bundle to use. 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 <Response>object
:rtype: requests.Response
Usage::
>>> import requests
>>> req = requests.request('GET', 'http://httpbin.org/get')
<Response [200]>
"""
# By using the 'with' statement we are sure the session is closed, thus we
# avoid leaving sockets open which can trigger a ResourceWarning in some
# cases, and look like a memory leak in others.
with sessions.Session() as session:
return session.request(method``=``method, url``=``url, ``*``*``kwargs)
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下面对源码中的各个属性进行分析
method和url
指名请求方式和请求路径
requests.request(method``=``'get'``, url``=``'http://127.0.0.1:8000/test/'``)
requests.request(method``=``'post'``, url``=``'http://127.0.0.1:8000/test/'``)
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params
requests模块发送请求有data、json、params三种携带参数的方法。
params在get请求中使用，data、json在post请求中使用。
params可以接收的参数：
- 可以是字典
- 可以是字符串
字典字符串都会被自动编码发送到url
- 可以是字节（必须是ascii编码以内）
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接收字典字符串都会被自动编码发送到url，如下
import requests
wd``=``'egon老师'
pn``=``1
response``=``requests.get(``'https://www.baidu.com/s'``,
params``=``{
'wd'``:wd,
'pn'``:pn
},
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.url)
# 输出为：https://www.baidu.com/s?wd=egon%E8%80%81%E5%B8%88&pn=1
# 可见url已被自动编码
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上面代码相当于如下代码，params编码转换本质上是用urlencode
import requests
from urllib.parse ``import urlencode
wd``=``'egon老师'
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'``,
})
print``(response.url)
# 输出为：https://www.baidu.com/s?wd=egon%E8%80%81%E5%B8%88&pn=1
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还有一点注意的就是接收字节数据时，不能传非ASCII码外的字符，如下就是错误的
import requests
# re = 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'))
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data
requests模块发送请求有data、json、params三种携带参数的方法。params在get请求中使用，data、json在post请求中使用。
data可以接收的参数为：字典，字符串，字节，文件对象，data和json两者的区别在于data的请求体为name=alex&age=18格式而json请求体为‘{'k1': 'v1', 'k2': '水电费'}’（字符串）
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'``}
)
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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'}
标志：payload
requests.request(method``=``'POST'``,
url``=``'http://127.0.0.1:8000/test/'``,
json``=``{``'k1'``: ``'v1'``, ``'k2'``: ``'水电费'``})
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headers
发送请求头到服务器
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'``}
)
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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)
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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)
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auth认证
解决浏览器的自带认证问题
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)
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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('.....')
image
HTTPBasicAuth实际是向浏览器发一个带有Authorization:.................的请求
HTTPBasicAuth
from requests.auth ``import HTTPBasicAuth, HTTPDigestAuth
ret ``= requests.get(``'https://api.github.com/user'``, auth``=``HTTPBasicAuth(``'wupeiqi'``, ``'sdfasdfasdf'``))
print``(ret.text)
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auth别的使用方式
# 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)
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timeout
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``)
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redirects
ret ``= requests.get(``'http://127.0.0.1:8000/test/'``, allow_redirects``=``False``)
print``(ret.text)
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proxies
代理设置
# 根据协议来确定发送请求时候的ip地址
proxies ``= {
"http"``: ``"61.172.249.96:80"``,
"https"``: ``"http://61.185.219.126:3128"``,
}
# 根据接收请求的地址来确定用什么地址发送
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)
#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)
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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)
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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)
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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)
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