mod_rewrite for URL with more than one variable - .htaccess

Question

Hi i'm trying to follow Mod_Rewrite for URL with multiple variables and edit it to suit my website but have a bit of a problem i have searched across the internet and could not really find anything which helps
I'm trying to turn example.com/editor/windows/chrome into this example.com?app=editor&os=windows&browser=chrome
Any ideas?
my current .htaccess file:
# Various rewrite rules.
<IfModule mod_rewrite.c>
RewriteEngine on
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^([a-zA-Z0-9_-]+)/?$ index.php?app=$1 [QSA]
RewriteRule ^([a-zA-Z0-9_-]+)/([a-zA-Z0-9_-]+)/?$ index.php?app=$1&os=$2&browser=$3 [QSA]
</IfModule>
I can get it to part work up-to example.com/editor/windows but can't get the third to include the browser

Answer 1

Your third rule doesn't include a capture group for the browser. This statement is missing:
RewriteRule ^([a-zA-Z0-9_-]+)/([a-zA-Z0-9_-]+)/([a-zA-Z0-9_-]+)$ index.php?app=$1&os=$2&browser=$3 [QSA]
RewriteRules are applied from top to bottom until [L] is found. Thus, in your question both rules are applied (which might casue bad performance).
A more clean version would be,
# Various rewrite rules.
<IfModule mod_rewrite.c>
RewriteEngine on
# don't rewrite URLs for existing files, directories or links
RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d [OR]
RewriteCond %{REQUEST_FILENAME} -l
RewriteRule .* - [L]
# now match the URIs according to OP needs
# Redirect example.com/editor and example.com/editor/ to example.com/index.php?app=editor and stop after this rule
RewriteRule ^([a-zA-Z0-9_-]+)/?$ index.php?app=$1 [QSA,L]
# Redirect example.com/editor/windows and example.com/editor/windows/ to example.com/index.php?app=editor&os=windows and stop after this rule
RewriteRule ^([a-zA-Z0-9_-]+)/([a-zA-Z0-9_-]+)/?$ index.php?app=$1&os=$2 [QSA,L]
# Redirect example.com/editor/windows/chrome and example.com/editor/windows/chrome/ to example.com/index.php?app=editor&os=windows&browser=chrome and stop after this rule
RewriteRule ^([a-zA-Z0-9_-]+)/([a-zA-Z0-9_-]+)/([a-zA-Z0-9_-]+)/?$ index.php?app=$1&os=$2&browser=$3 [QSA,L]
</IfModule>
However, the last three RewriteRule rules can also be compiled to one:
RewriteRule ^([a-zA-Z0-9_-]+)(?:/([a-zA-Z0-9_-]+)(?:/([a-zA-Z0-9_-]+)))/?$ index.php?app=$1&os=$2&browser=$3 [QSA,L]

Answer 2

As long as you don't mind having blank $_GET[] variables, you can reduce it all down to a single rule. Also not that you have 2 conditions that check for !-f and !-d. Those conditions only apply to the immediately following rule, and will not apply to any other rules unless you duplicate the condition.
So you can try:
# Various rewrite rules.
<IfModule mod_rewrite.c>
RewriteEngine on
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^([a-zA-Z0-9_-]+)(?:/([a-zA-Z0-9_-]+)|)(?:/([a-zA-Z0-9_-]+)|)/?$ index.php?app=$1&os=$2&browser=$3 [L,QSA]
</IfModule>