requests【请求库】

"""
python请求库的使用-----requests
requests源于urllib3,Apache2协议
requests库的使用思路:
1.导入requests包
2.响应头response=requests.get(url,headers,params)
  传递url参数,params={'key1':'value','key2':'value'}
3.返回响应头内容及编码raise_for_status
  response.encoding = apparent_encoding
  response.content(二进制内容)
  response.text
  response.json()返回json格式
  response.url传递的url
 编码也可以用codecs模块
4.原始响应内容:
  r=requests.get(url,stream=True)
  r.raw
  r.raw.read()---二进制数据
5.保存文本流保存到文件:
 with open(filename,'wb') as fd:
       for chunk in r.iter_content(chunk_size):
          fd.write(chunk)
6.上传:
  url = 'http://httpbin.org/post'
  files = {'file': open('report.xls', 'rb')}
   r = requests.post(url, files=files)
7.重定向
  
r = requests.get('http://',allow_redirects=False)
r.status_code
r.history ---- 查看结果

8.超时
r = requests.get('http://',timrout=1)

9.会话对象
s = requests.Session()
s.get('http://')
r = s.get("http://")

(2.会话也可以用来为请求方法提供缺省数据
s = requests.Session()
s.auth = ('user','pass')
s.headers.update({'x-test':'true'})
#both 'x-test' and 'x-test2' are sent
s.get('http://',headers={'x-test2':'true'})

(3.cookie上传
s = requests.Session()
r = s.get(url,cookies={'from-my':'browser'})
print(r.text)


with requests.Session() as s:
     s.get(url)

10.准备的请求
from requests import Request,Session

s = Session()
req = Request('GET',url,data=data,headers=header)
prepped = req.prepare()
resp = s.send(prepped,stream=stream,verify=verify,proxies=proxies,cert=cert,timeout=timeout)

print(resp.status_code)

####
from requests import Request,Session

s = Session()
req = Request('GET',url,data=data,headers=headers)
prepped = s.prepare_request(req)
resp = s.send(prepped,stream=stream,verify=verify,proxies=proxies,cert=cert,timeout=timeout)
print(resp.status_code)

11.SSL证书验证
requests.get(url,verify=True)
requests.get(url,cert=('/path/client.cert','/path/client.key'))

s = requests.Session()
s.cert = '/path/client.cert'

12.流式上传

with open('massive-body') as f:
    requests.post('https://',data=f)

13.POST多个分块编码的文件

url = 'http://httpbin.org/post'
#(form_field_name,file_info)
multiple_files =[('images',('foo.png',open('foo.png','rb'),'image/png')),('images',('bar.png',open('bar.png','rb'),'image/png'))]

14.事件钩子
def print_url(r,*args,**kwargs):
   print(r.url)

requests.get(url,hooks=dict(response=print_url))

15.自定义身份验证
from requests.auth import AuthBase

class PizzaAuth(AuthBase):
     def __init__(self,username):
          self.username = username
     def __call__(self,r):
          r.headers['X-pizza'] = self.name
          return r
然后我们就可以使用PizzaAuth来进行网络请求:
    requests.get(url,auth=PizzaAuth('ZYL'))

16流式请求
import json
import requests

r = requests.get(url,stream=True)
for line in r.iter_lines():
      if line:
          decoded_line = line.decode('utf-8')
          print(json.loads(decoded_line))

#######
r = requests.get(url,stream=True)
if r.encoding is None:
    r.encoding = 'utf-8'
for line in r/iter_lines(decode_unicode=True):
     if line:
        print(json.loads(line))


   

"""

requests的get请求

#参考方法在demand.py
import requests
from requests import codes



def get_html(url):
    try:
        #请求头文件
        headers ={"User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.98 Safari/537.36"}
        #请求
        s = requests.Session()
        r = s.get(url,headers=headers,timeout=1)
        #错误抛出
        r.raise_for_status()
        #编码设置
        r.encoding = r.apparent_encoding
        #判断是否请求成功
        if r.status_code == codes.ok:
            #网页代码
            html = r.text
            with open("demo.html","w",encoding="utf-8") as f:
                f.write(html)
        return html
    except:
         print("失败!")
         
def main():
    url = input("请输入要爬取的网站地址:")
    html = get_html(url)
    print(html)
    
if __name__ == "__main__":
    main()
    

 

"""python请求库的使用-----requestsrequests源于urllib3,Apache2协议requests库的使用思路:1.导入requests包2.响应头response=requests.get(url,headers,params)  传递url参数,params={'key1':'value','key2':'value'}3.返回响应头内容及编码raise_for_status  response.encoding = apparent_encoding  response.content(二进制内容)  response.text  response.json()返回json格式  response.url传递的url 编码也可以用codecs模块4.原始响应内容:  r=requests.get(url,stream=True)  r.raw  r.raw.read()---二进制数据5.保存文本流保存到文件: with open(filename,'wb') as fd:       for chunk in r.iter_content(chunk_size):          fd.write(chunk)6.上传:  url = 'http://httpbin.org/post'  files = {'file': open('report.xls', 'rb')}   r = requests.post(url, files=files)7.重定向  r = requests.get('http://',allow_redirects=False)r.status_coder.history ---- 查看结果
8.超时r = requests.get('http://',timrout=1)
9.会话对象s = requests.Session()s.get('http://')r = s.get("http://")
(2.会话也可以用来为请求方法提供缺省数据s = requests.Session()s.auth = ('user','pass')s.headers.update({'x-test':'true'})#both 'x-test' and 'x-test2' are sents.get('http://',headers={'x-test2':'true'})
(3.cookie上传s = requests.Session()r = s.get(url,cookies={'from-my':'browser'})print(r.text)

with requests.Session() as s:     s.get(url)
10.准备的请求from requests import Request,Session
s = Session()req = Request('GET',url,data=data,headers=header)prepped = req.prepare()resp = s.send(prepped,stream=stream,verify=verify,proxies=proxies,cert=cert,timeout=timeout)
print(resp.status_code)
####from requests import Request,Session
s = Session()req = Request('GET',url,data=data,headers=headers)prepped = s.prepare_request(req)resp = s.send(prepped,stream=stream,verify=verify,proxies=proxies,cert=cert,timeout=timeout)print(resp.status_code)
11.SSL证书验证requests.get(url,verify=True)requests.get(url,cert=('/path/client.cert','/path/client.key'))
s = requests.Session()s.cert = '/path/client.cert'
12.流式上传
with open('massive-body') as f:    requests.post('https://',data=f)
13.POST多个分块编码的文件
url = 'http://httpbin.org/post'#(form_field_name,file_info)multiple_files =[('images',('foo.png',open('foo.png','rb'),'image/png')),('images',('bar.png',open('bar.png','rb'),'image/png'))]
14.事件钩子def print_url(r,*args,**kwargs):   print(r.url)
requests.get(url,hooks=dict(response=print_url))
15.自定义身份验证from requests.auth import AuthBase
class PizzaAuth(AuthBase):     def __init__(self,username):          self.username = username     def __call__(self,r):          r.headers['X-pizza'] = self.name          return r然后我们就可以使用PizzaAuth来进行网络请求:    requests.get(url,auth=PizzaAuth('ZYL'))
16流式请求import jsonimport requests
r = requests.get(url,stream=True)for line in r.iter_lines():      if line:          decoded_line = line.decode('utf-8')          print(json.loads(decoded_line))
#######r = requests.get(url,stream=True)if r.encoding is None:    r.encoding = 'utf-8'for line in r/iter_lines(decode_unicode=True):     if line:        print(json.loads(line))

   
"""