.htaccess how to serve contents from different directory for mobile and desktop? - apache

Question

I have two version of my site. one is a mobile version and another one is desktop.
Path looks like this :
For Mobile : public_htm/mobile
For Desktop : public_html
I want to change the document root of my domain based on the device. I want to serve content from the mobile folder if the user's device is mobile & serve contents from public_html if user on desktop.
How can I do this with .htaccess?
I want to have my domain the same for both desktop and mobile, only document root changed by .htaccess based on the device.

Answer 1

You would need to add something like the following to the top of the root .htaccess file:
RewriteEngine On
# Prevent direct access to the "/mobile" subdirectory
# - redirect back to the root
RewriteCond %{ENV:REDIRECT_STATUS} ^$
RewriteRule ^mobile/(.*) /$1 [R=301,L]
# Rewrite all requests from mobile devices to the "/mobile" site
RewriteCond %{HTTP_USER_AGENT} ^iphone|android|etc$ [NC]
RewriteRule ^(?!mobile/).* mobile/$0 [L]
The mobile detection regex (RewriteCond directive) is just an example, the specifics are left up to the reader. (For reference: mobile browser user-agent strings)
The negative lookahead in the RewriteRule pattern prevents requests that have already been rewritten to the /mobile subdirectory from being repeatedly rewritten. If you have another .htaccess in the /mobile subdirectory containing mod-rewrite directives then this may be unnecessary.
The first rule redirects any direct traffic to the /mobile subdirectory back to the document root. However, if you have another .htaccess file in the /mobile subdirectory containing mod-rewrite directives then this redirect would need to be moved to that .htaccess file (it won't work here).
Just a note on terminology... This doesn't strictly change the "document root", as mentioned in the question. (Although it might "look like" it does from a client perspective.) This internally rewrites requests to a subdirectory (URL-rewriting). Server-side applications running in the /mobile subdirectory still see the document root as being the parent directory. You cannot change the "document root" in .htaccess, which can only be done by setting the DocumentRoot (or VirtualDocumentRoot) directive(s) in the server config.