htaccess url rewrite confusion about request_uri

Question

I'm (sometimes) somehow managing to url rewriting successfully but I want to understand the core of what I'm actually doing.

Now, whenever I type http://localhost/admin/shop/ to the browser's address bar, I'd like my htaccess to rewrite the url as http://localhost/admin.php?page=shop so in the php I can understand that I'm actually dealing with shop page. For this, I have:

RewriteEngine on
RewriteRule ^(.*)\$ $1.php [nc]

RewriteCond %{REQUEST_URI} ^/admin\.php/[^/]+/$
RewriteRule ^admin\.php/(.*)/$ admin\.php?pval=$1 [l,nc]

This works so far. But I'd like to understand why my code doesn't work when I do this:

###RewriteEngine on
###RewriteRule ^(.*)\$ $1.php [nc]

### note the commenting out the code above    

RewriteCond %{REQUEST_URI} ^/admin/[^/]+/$
RewriteRule ^admin/(.*)/$ admin?pval=$1 [l,nc]

### note the removal of '\.php' 

So basically, when you type 'http://localhost/admin/shop/' to the address bar, php's $_SERVER['REQUEST_URI'] will print out exactly /admin/shop/. Now, assuming php's REQUEST_URI is like that, htaccess REQUEST_URI should be the same right? I don't really know if they are using different engines but that's what comes logical to me. So, assuming that I'm right, why the second example doesn't work when I remove the '.php' from the RewriteCond and RewriteRule? Also, if I'd had the chance to print the REQUEST_URI of htaccess, what would it actually print to the screen in the above example?

PS: I know that for this case, I don't really need to use htaccess as I can create a folder inside admin folder and name it shop and so on. But the thing is that I don't really have an admin folder as I'm using controllers and a simple switch in the admin.php to avoid creating millions of folders inside my application. This is just simpler to me.

Answer 1

§

The reason your amended rule doesn't work is probably because you omitted the .php from the url-path. Assuming you have an admin.php file hosted in the root this should work:

RewriteCond %{REQUEST_URI} ^/admin/[^/]+/$
RewriteRule ^admin/(.*)/$ /admin.php?pval=$1 [L,NC]

§

Removing this

RewriteRule ^(.*)\$ $1.php [nc]

probably didn't cause any problems as it probably wasn't matching anything. The pattern ends with escaped dollar sign \$ which matches the $ character and not the end of line meta-character. So that rule matches any path that contains a dollar sign.

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Is Apache's %{REQUEST_URI} variable the same as PHP's $_SERVER['REQUEST_URI']?

More or less. But, for instance, if you did any rewriting with redirects you might get confused because the redirect will create a new, rewritten request. That's a specious example, but there could be other advanced use cases to watch out for. For simple cases, they are the same.

Answer 2

Just a thought, i think the last slash doesn't let it match a .php file, ie: does http://localhost/admin/shop give you the same page as http://localhost/admin/shop/ ?

Try changing it to:

RewriteRule ^admin/(.*)$ admin\.php?pval=$1 [l,nc]

Answer 3

If you are using a .htaccess file to do mod_rewrite goodness, REQUEST_URI doesn't have the beginning slash, so for example /admin/shop/ -> admin/shop/

And to "debug" mod_rewrite you have to setup the "RewriteLog" directive in your conf file, something like this:

RewriteLog "C:/wamp/logs/rewrite.log"
RewriteLogLevel 9