python requests用法总结

python requests用法总结

requests是一个很实用的Python HTTP客户端库，编写爬虫和测试服务器响应数据时经常会用到。可以说，Requests 完全满足如今网络的需求

本文全部来源于官方文档:

   http://docs.python-requests.org/en/master/
   http://cn.python-requests.org/zh_CN/latest/ 

安装方式一般采用pip install requests。其它安装方式参考官方文档

导入模块： import requests

一、GET请求

r  = requests.get('http://httpbin.org/get')

传参

>>> payload = {'key1': 'value1', 'key2': 'value2', 'key3': None}

>>> r = requests.get('http://httpbin.org/get', params=payload)

http://httpbin.org/get?key2=value2&key1=value1

Note that any dictionary key whose value is None will not be added to the URL's query string.

参数也可以传递列表

>>> payload = {'key1': 'value1', 'key2': ['value2', 'value3']}

>>> r = requests.get('http://httpbin.org/get', params=payload)

>>> print(r.url)

http://httpbin.org/get?key1=value1&key2=value2&key2=value3

r.text        返回headers中的编码解析的结果，可以通过r.encoding = 'gbk'来变更解码方式

r.content     返回二进制结果

r.json()      返回JSON格式，可能抛出异常

r.status_code

r.raw         返回原始socket respons，需要加参数stream=True

>>> r = requests.get('https://api.github.com/events', stream=True)

>>> r.raw

<requests.packages.urllib3.response.HTTPResponse object at 0x101194810>

>>> r.raw.read(10)

'\x1f\x8b\x08\x00\x00\x00\x00\x00\x00\x03'

将结果保存到文件，利用r.iter_content()

with open(filename, 'wb') as fd:

    for chunk in r.iter_content(chunk_size):

        fd.write(chunk)

传递headers

>>> headers = {'user-agent': 'my-app/0.0.1'}

>>> r = requests.get(url, headers=headers)

传递cookies

>>> url = 'http://httpbin.org/cookies'

>>> r = requests.get(url, cookies=dict(cookies_are='working'))

>>> r.text

'{"cookies": {"cookies_are": "working"}}'

二、POST请求

传递表单

r = requests.post('http://httpbin.org/post', data = {'key':'value'})

通常，你想要发送一些编码为表单形式的数据—非常像一个HTML表单。 要实现这个，只需简单地传递一个字典给 data 参数。你的数据字典在发出请求时会自动编码为表单形式:

>>> payload = {'key1': 'value1', 'key2': 'value2'}

>>> r = requests.post("http://httpbin.org/post", data=payload)

>>> print(r.text)

{

  ...

  "form": {

    "key2": "value2",

    "key1": "value1"

  },

  ...

}

很多时候你想要发送的数据并非编码为表单形式的。如果你传递一个 string 而不是一个dict ，那么数据会被直接发布出去。

>>> url = 'https://api.github.com/some/endpoint'

>>> payload = {'some': 'data'}

>>> r = requests.post(url, data=json.dumps(payload))

或者

>>> r = requests.post(url, json=payload)

传递文件

url = 'http://httpbin.org/post'

>>> files = {'file': open('report.xls', 'rb')}

>>> r = requests.post(url, files=files)

配置files，filename, content_type and headers

files = {'file': ('report.xls', open('report.xls', 'rb'), 'application/vnd.ms-excel', {'Expires': '0'})}

files = {'file': ('report.csv', 'some,data,to,send\nanother,row,to,send\n')}

响应

r.status_code

r.heards

r.cookies

跳转

By default Requests will perform location redirection for all verbs except HEAD.

>>> r = requests.get('http://httpbin.org/cookies/set?k2=v2&k1=v1')

>>> r.url

'http://httpbin.org/cookies'

>>> r.status_code

200

>>> r.history

[<Response [302]>]

If you're using HEAD, you can enable redirection as well:

r = requests.head('http://httpbin.org/cookies/set?k2=v2&k1=v1',allow_redirects=True)

You can tell Requests to stop waiting for a response after a given number of seconds with the timeoutparameter:

requests.get('http://github.com', timeout=0.001)

参考文章：http://www.cnblogs.com/lilinwei340/p/6417689.html