如何检查网站的移动版本？

Question

I would like to check if mobile version exists for a specific website or not. To my understanding, we cannot be sure if every website has mobile version located at http://m.example.com/ therefore I am testing through CURL() request. Here is how I am doing it:

* I send mobile browser headers in curl request, this returns contents of 
the returning URL. 
* If it has a mobile version, then it would return contents of a mobile version site.
* I then check if the content includes @media keyword, if it exists then I assume it has a mobile version.

The problem is, if its css loads externally then I will have to further send CURL() requests to the CSS files as well, which will make it even more slower. Is there any specific solution to my problem or can I boost this process a bit more?

Any help would be appreciated. Thanks.

Answer 1

The problem with your approach, which smells a bit like an XY Problem , is that it is simply unreliable.

The website has many choices for mobile websites, which include:

The problem with this method is twofold. For starters, you would have to scan every single CSS file and <link> declaration. Secondly, the site can dynamically introduce stylesheets to the page using JavaScript, which you will never see using cURL because it lacks a JavaScript parser.

Again, this JavaScript will never get executed, so you will never see that result.

Well, I guess you could try to use a mobile user-agent string with your cURL request, and see where that takes you, but all of these methods are hackish and unreliable.

As @Quentin mentioned in the comments, the page could be mobile friendly without any additional checks on the client/server side (responsive design without media queries, by simply using percentage-based values, for example).