python: 爬虫利器requests

requests并不是系统自带的模块，他是第三方库，需要安装才能使用

闲话少说，来，让我们上代码：
简单的看一下效果：

import requests
requests = requests.session()
headers = {
    'User-Agent':'Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:57.0) Gecko/20100101 Firefox/57.0'
}
url = "http://httpbin.org"
response = requests.get(url, headers=headers, timeout=None)
print(response.text)
print(response.cookies)
print(response.content)
print(response.content.decode("utf-8"))
print(respone.json())

基本的post请求：

data = {
    "name":"zhaofan",
    "age":23
}
response = requests.post("http://httpbin.org/post",data=data)
print(response.text)

对于无效的网站证书请求方法：

import requests
from requests.packages import urllib3
urllib3.disable_warnings()
response = requests.get("https://www.12306.cn",verify=False)
print(response.status_code)

代理设置：

import requests

proxies= {
    "http":"http://127.0.0.1:9999",
    "https":"http://127.0.0.1:8888"
}
response  = requests.get("https://www.baidu.com",proxies=proxies)
print(response.text)

如果代理需要设置账户名和密码,只需要将字典更改为如下：
proxies = {
"http":"http://user:password@127.0.0.1:9999"
}
如果你的代理是通过sokces这种方式则需要pip install "requests[socks]"
proxies= {
"http":"socks5://127.0.0.1:9999",
"https":"sockes5://127.0.0.1:8888"
}

超时设置

通过timeout参数可以设置超时的时间

没有超时时间，一直等待
timeout=None

异常捕捉：

import requests

from requests.exceptions import ReadTimeout,ConnectionError,RequestException

try:
    response = requests.get("http://httpbin.org/get",timout=0.1)
    print(response.status_code)
except ReadTimeout:
    print("timeout")
except ConnectionError:
    print("connection Error")
except RequestException:
    print("error")