【转】Python3中urllib详细使用方法(header,代理,超时,认证,异常处理)

 

urllib是python的一个获取url(Uniform Resource Locators,统一资源定址器)了，咱们能够利用它来抓取远程的数据进行保存哦，下面整理了一些关于urllib使用中的一些关于header,代理,超时,认证,异常处理处理方法，下面一块儿来看看。

 

python3 抓取网页资源的 N 种方法

一、最简单

1 import urllib.request 2 3 response = urllib.request.urlopen('http://python.org/') 4 5 html = response.read()

 

二、使用 Request

1 import urllib.request 2 3 req = urllib.request.Request('http://python.org/') 4 5 response = urllib.request.urlopen(req) 6 7 the_page = response.read()

 

三、发送数据

 1 #! /usr/bin/env python3  2  3 import urllib.parse  4  5 import urllib.request  6  7 url = 'http://localhost/login.php'  8  9 user_agent = 'Mozilla/4.0 (compatible; MSIE 5.5; Windows NT)' 10 11 values = { 'act' : 'login', 'login[email]' : 'abc@abc.com', 'login[password]' : '123456' } 12 13 data = urllib.parse.urlencode(values) 14 15 req = urllib.request.Request(url, data) 16 17 req.add_header('Referer', 'http://www.python.org/') 18 19 response = urllib.request.urlopen(req) 20 21 the_page = response.read() 22 23 print(the_page.decode("utf8"))

 

四、发送数据和header

 1 #! /usr/bin/env python3  2  3 import urllib.parse  4  5 import urllib.request  6  7 url = 'http://localhost/login.php'  8  9 user_agent = 'Mozilla/4.0 (compatible; MSIE 5.5; Windows NT)' 10 11 values = { 'act' : 'login', 'login[email]' : 'abc@abc.com', 'login[password]' : '123456' } 12 13 headers = { 'User-Agent' : user_agent } 14 15 data = urllib.parse.urlencode(values) 16 17 req = urllib.request.Request(url, data, headers) 18 19 response = urllib.request.urlopen(req) 20 21 the_page = response.read() 22 23 print(the_page.decode("utf8"))

 

五、http 错误

 1 #! /usr/bin/env python3  2  3 import urllib.request  4  5 req = urllib.request.Request('http://python.org/')  6  7 try:  8  9 　　urllib.request.urlopen(req) 10 11 except urllib.error.HTTPError as e: 12 13 　　print(e.code) 14 15 print(e.read().decode("utf8"))

 

六、异常处理1

 1 #! /usr/bin/env python3  2  3 from urllib.request import Request, urlopen  4  5 from urllib.error import URLError, HTTPError  6  7 req = Request('http://www.python.org/')  8  9 try: 10 11 　　response = urlopen(req) 12 13 except HTTPError as e: 14 15 　　print('The (www.python.org)server couldn't fulfill the request.') 16 17 　　print('Error code: ', e.code) 18 19 except URLError as e: 20 21 　　print('We failed to reach a server.') 22 23 　　print('Reason: ', e.reason) 24 25 else: 26 27 　　print("good!") 28 29 　　print(response.read().decode("utf8")) 

 

七、异常处理2

 1 #! /usr/bin/env python3  2  3 from urllib.request import Request, urlopen  4  5 from urllib.error import URLError  6  7 req = Request("http://www.python.org/")  8  9 try: 10 11 　　response = urlopen(req) 12 13 except URLError as e: 14 15 　　if hasattr(e, 'reason'): 16 17 　　　　print('We failed to reach a server.') 18 19 　　　　print('Reason: ', e.reason) 20 21 　　elif hasattr(e, 'code'): 22 23 　　　　print('The server couldn't fulfill the request.') 24 25 　　　　print('Error code: ', e.code) 26 27 else: print("good!") 28 29 　　print(response.read().decode("utf8"))

 

八、HTTP 认证

 1 #! /usr/bin/env python3  2  3 import urllib.request  4  5 # create a password manager  6  7 password_mgr = urllib.request.HTTPPasswordMgrWithDefaultRealm()  8  9 # Add the username and password. 10 11 # If we knew the realm, we could use it instead of None. 12 13 top_level_url = "https://www.python.org/" 14 15 password_mgr.add_password(None, top_level_url, 'rekfan', 'xxxxxx') 16 17 handler = urllib.request.HTTPBasicAuthHandler(password_mgr) 18 19 # create "opener" (OpenerDirector instance) 20 21 opener = urllib.request.build_opener(handler) 22 23 # use the opener to fetch a URL 24 25 a_url = "https://www.python.org/" 26 27 x = opener.open(a_url) 28 29 print(x.read()) 30 31 # Install the opener. 32 33 # Now all calls to urllib.request.urlopen use our opener. 34 35 urllib.request.install_opener(opener) 36 37 a = urllib.request.urlopen(a_url).read().decode('utf8') 38 39 print(a)

 

九、使用代理

 1 #! /usr/bin/env python3  2  3 import urllib.request  4  5 proxy_support = urllib.request.ProxyHandler({'sock5': 'localhost:1080'})  6  7 opener = urllib.request.build_opener(proxy_support)  8  9 urllib.request.install_opener(opener) 10 11 a = urllib.request.urlopen("http://www.python.org/").read().decode("utf8") 12 13 print(a)

 

十、超时

 1 #! /usr/bin/env python3  2  3 import socket  4  5 import urllib.request  6  7 # timeout in seconds  8  9 timeout = 2 10 11 socket.setdefaulttimeout(timeout) 12 13 # this call to urllib.request.urlopen now uses the default timeout 14 15 # we have set in the socket module 16 17 req = urllib.request.Request('http://www.python.org/') 18 19 a = urllib.request.urlopen(req).read() 20 21 print(a)

来源：http://www.cnblogs.com/ifso/p/4707135.html