How to force mod_rewrite to skip real files - regex

Question

I have an application that routes all requests through index.php.
Here's my setup:
I access the application at http://www.example.com/sample/
On the filesystem, the application sits in /home/chris/www/sample/
The web-accessible directory of the application lives at /home/chris/www/sample/app/web.
The DocumentRoot is set to /home/chris/www
/home/chris/www/sample/.htaccess is configured as follows:
RewriteEngine on
RewriteCond %{REQUEST_URI} ^/sample/(.+)$
RewriteCond %{DOCUMENT_ROOT}/sample/app/web/%1 -f
RewriteRule ^/sample/(.*)$ %{DOCUMENT_ROOT}/sample/app/web/%1 [L]
RewriteRule ^(.+)$ index.php?ws_page=$1 [L,NC,QSA]
I've tried multiple configurations, but haven't figured out why I keep getting 404's on calls to "real" files.
Sample 404:
`http://www.example.com/sample/_css/960/reset.css`
(which I want to have rewritten to /home/chris/www/sample/app/web/_css/960/reset.css)
EDIT
I have already tried
RewriteCond %{REQUEST_URI} !-f
RewriteCond %{REQUEST_URI} !-d
RewriteCond %{REQUEST_URI} !-l
and they did not work, because the %{REQUEST_URI} prefix does not match the filesystem prefix of these files.
EDIT 2
To clarify, I want requests of the form
`http://www.example.com/sample/foo/bar`
to be rewritten to the filesystem object /home/chris/www/sample/app/web/foo/bar, but only if that filesystem object exists.

Answer 1

One of the biggest bear-pits in reading the mod_rewrite documentation in the difference in behaviour in a system (that this the main and vhost configs that apache reads on start-up and those directive processes in a per-directory context. See the Per-directory Rewrites subsection of the RewriteRule documentation for further details.
When using the rewrite engine in .htaccess files the per-directory prefix (which always is the same for a specific directory) is automatically removed for the RewriteRule pattern matching and automatically added after any relative (not starting with a slash or protocol name) substitution encounters the end of a rule set. See the RewriteBase directive for more information regarding what prefix will be added back to relative substitions.
and later
The removed prefix always ends with a slash, meaning the matching occurs against a string which never has a leading slash. Therefore, a Pattern with ^/ never matches in per-directory context. What you've done is to code around this.
Incidentally, this is why it is always safer to specify a RewriteBase, as the engine gets this wrong without this.
BTW, this second quote can be wrong because the prefix add-back occurs at the then of the rule set execution, and if you have a successful rule which is to a different relative branch (that is the target starts with a /) but without the [L] flag set, then the engine falls through to any subsequent rules with a leading / set. Most confusing, so my general advice is never rely on fall-through rules. Always force an immediate internal or external redirect on a successful substitution in a per-directory context as the engine has this and a couple of other bugs in this fall-through processing.

Answer 2

Have your code like this:
Options +FollowSymLinks -MultiViews
# Turn mod_rewrite on
RewriteEngine On
RewriteBase /sample
RewriteCond %{THE_REQUEST} ^[A-Z]{3,}\s/+sample/(.+)\s [NC]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond /home/chris/www/sample/app/web/%1 -f [NC]
RewriteRule ^ /sample/app/web/%1 [L]
# If the request is not for a valid file
RewriteCond %{REQUEST_FILENAME} !-f
# If the request is not for a valid symlink
RewriteCond %{REQUEST_FILENAME} !-l
# If the request is not for a valid directory
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.+)$ index.php?page=$1 [L,QSA]

Answer 3

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
These two rules will skip files (-f) and directories (-d) which actually exist.

Answer 4

Mad bonus points to whomever can explain to me why my the EOS anchor ($) was to blame for the RewriteRule not working.
I wound up with this:
RewriteEngine on
RewriteCond %{REQUEST_URI} ^/sample/(.+)
RewriteCond %{DOCUMENT_ROOT}/sample/app/web/%1 -f
RewriteRule ^(.*)$ app/web/$1 [L,NC,QSA]
RewriteCond %{REQUEST_URI} !(^/sample/app/web)
RewriteRule ^(.+)$ index.php?ws_page=$1 [L,NC,QSA]
Many thanks to all who helped me diagnose this weirdness.