python requests学习

1、无参数直接get

>>> import requests
>>> r  = requests.get("http://httpbin.org/get")

>>> r.status_code
200
>>> print(r.text)
{
  "args": {},
  "headers": {
    "Accept": "*/*",
    "Accept-Encoding": "gzip, deflate",
    "Host": "httpbin.org",
    "User-Agent": "python-requests/2.9.1"
  },
  "origin": "110.184.65.255",
  "url": "http://httpbin.org/get"
}

同时支持json直接获取json解码后结果

>>> r.json()
{‘args‘: {}, ‘origin‘: ‘110.184.65.255‘, ‘url‘: ‘http://httpbin.org/get‘, ‘headers‘: {‘Accept‘: ‘*/*‘, ‘Accept-Encoding‘: ‘gzip, deflate‘, ‘Host‘: ‘httpbin.org‘, ‘User-Agent‘: ‘python-requests/2.9.1‘}}

2、有参数的get，制定params的参数的值。

>>> payload = {‘name‘:‘felix‘,‘password‘:‘12345678‘}
>>> r = requests.get(‘http://httpbin.org/get‘,params=payload)
>>> print(r.url)
http://httpbin.org/get?name=felix&password=12345678
>>> r.status_code
200
>>> print(r.text)
{
  "args": {
    "name": "felix",
    "password": "12345678"
  },
  "headers": {
    "Accept": "*/*",
    "Accept-Encoding": "gzip, deflate",
    "Host": "httpbin.org",
    "User-Agent": "python-requests/2.9.1"
  },
  "origin": "110.184.65.255",
  "url": "http://httpbin.org/get?name=felix&password=12345678"
}

可以用r.url打印生成的url.

3、修改HTTP头内容

>>> headers={‘user-agent‘:"IE9.0"}
>>> r = requests.get("http://httpbin.org/get",headers=headers)

4、POST方法, form格式

>>> payload
{‘name‘: ‘felix‘, ‘password‘: ‘12345678‘}
>>> r = requests.post("http://httpbin.org/post",data=payload)
>>> r.status_code
200
>>> print(r.text)
{
  "args": {},
  "data": "",
  "files": {},
  "form": {
    "name": "felix",
    "password": "12345678"
  },
  "headers": {
    "Accept": "*/*",
    "Accept-Encoding": "gzip, deflate",
    "Content-Length": "28",
    "Content-Type": "application/x-www-form-urlencoded",
    "Host": "httpbin.org",
    "User-Agent": "python-requests/2.9.1"
  },
  "json": null,
  "origin": "110.184.65.255",
  "url": "http://httpbin.org/post"
}

json格式

>>> r = requests.post("http://httpbin.org/post",json=payload,headers=headers)
>>> print(r.text)
{
  "args": {},
  "data": "{\"name\": \"felix\", \"password\": \"12345678\"}",
  "files": {},
  "form": {},
  "headers": {
    "Accept": "*/*",
    "Accept-Encoding": "gzip, deflate",
    "Content-Length": "41",
    "Content-Type": "application/json",
    "Host": "httpbin.org",
    "User-Agent": "IE9.0"
  },
  "json": {
    "name": "felix",
    "password": "12345678"
  },
  "origin": "110.184.65.255",
  "url": "http://httpbin.org/post"
}

字符串格式：

r = requests.post(‘http://httpbin.org/post‘, data=json.dumps(payload))

5、超时

>>> r=requests.get("https://www.baidu.com",timeout=0.1)
>>> r=requests.get("https://www.baidu.com",timeout=0.005)
Traceback (most recent call last):
  File "C:\Python34\lib\site-packages\requests\packages\urllib3\connection.py", line 137, in _new_conn

Errors and Exceptions

In the event of a network problem (e.g. DNS failure, refused connection, etc), Requests will raise aConnectionError exception.

In the rare event of an invalid HTTP response, Requests will raise an HTTPError exception.

If a request times out, a Timeout exception is raised.

If a request exceeds the configured number of maximum redirections, a TooManyRedirects exception is raised.

All exceptions that Requests explicitly raises inherit from requests.exceptions.RequestException.

更多信息详见：http://www.python-requests.org/en/master/user/quickstart/