问题
I'm looking for a way to compare two urls. I can do:
URI('http://www.test.com/blabla').host
to have the base name, but this not reliable. For example:
URI('http://www.test.com/blabla').host == URI('http://test.com/blabla').host
returns false, but they can be the same site. To have the IP address is not reliable too because if I do:
IPSocket.getaddress(URI('http://hello.herokuapp.com').host) ==
IPSocket.getaddress(URI('http://test.herokuapp.com').host)
It returns true, but they are not the same site. Is there a more reliable way?
回答1:
The site under http://foo.com can be the same as under http://www.foo.com, but it can be a totally different site, due to web server configuration. It depends on the DNS config too, which IP points to www and which one to without www.
If you want compare two sites, you need to fetch the content, and compare key parts (using nokogiri for example) about similarities.
Nowadays due to sidebars and news, two consequent request to the same url, gives slight different html responses.
来源：https://stackoverflow.com/questions/22283240/check-if-two-urls-are-for-the-same-website