Python Scraping，网页不存在但​​网站重定向到另一个页面

Question

i am trying to find a way to know that if a web page exists or not. there are plenty of methods like httlib2, urlparse and using requests . but in my case the website redirects me to the home page if the webpage doesnot exist eg https://www.thenews.com.pk/latest/category/sports/2015-09-21

Is there any method to catch that ?

Answer 1

You can check if the final url is the one you get redirected to, as well as if there was any history of redirects.

>>> import requests
>>> target_url = "https://www.thenews.com.pk/latest/category/sports/2015-09-21"
>>> response = requests.get(target_url)
>>> response.history[0].url
u'https://www.thenews.com.pk/latest/category/sports/2015-09-21'
>>> response.url
u'https://www.thenews.com.pk/'
>>> response.history and response.url == 'https://www.thenews.com.pk/' != target_url
True

Answer 2

The URL you mention gives a Redirect return code (307) which you can catch. See here:

$ curl -i https://www.thenews.com.pk/latest/category/sports/2015-09-21
HTTP/1.1 307 Temporary Redirect
Date: Sun, 26 Mar 2017 10:13:39 GMT
Content-Type: text/html; charset=UTF-8
Transfer-Encoding: chunked
Connection: keep-alive
Set-Cookie: __cfduid=ddcd246615efb68a7c72c73f480ea81971490523219; expires=Mon, 26-Mar-18 10:13:39 GMT; path=/; domain=.thenews.com.pk; HttpOnly
Set-Cookie: bf_session=b02fb5b6cc732dc6c3b60332288d0f1d4f9f7360; expires=Sun, 26-Mar-2017 11:13:39 GMT; Max-Age=3600; path=/; HttpOnly
Expires: Thu, 19 Nov 1981 08:52:00 GMT
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Pragma: no-cache
Location: https://www.thenews.com.pk/
X-Cacheable: YES
X-Varnish: 654909723
Age: 0
Via: 1.1 varnish
X-Age: 0
X-Cache: MISS
Access-Control-Allow-Origin: *
Server: cloudflare-nginx
CF-RAY: 345956a8be8a7289-AMS