Different FastCGI backend for /subdir: regex not matching

Server NGINX
1

I have a virtual host, and for a certain subdirectory I want to use
another fastcgi backend.

What I have now goes something like:
(…)
location ~ /subdir/ {
alias /var/www/otheraccount/public_html/;

            # PHP FastCGI
            location ^~ /subdir\/(.+)\.php {
                    return 504;
                    include /usr/pkg/etc/nginx/fastcgi_params;

                    fastcgi_pass 127.0.0.1:9000;
                    fastcgi_index index.php;
                    fastcgi_param SCRIPT_FILENAME

/var/www/othervhost/public_html$fastcgi_script_name;

                    try_files $uri =502;
            }
   }

    # PHP FastCGI
    location ~ \.php {
            include /usr/pkg/etc/nginx/fastcgi_params;

            fastcgi_pass 127.0.0.1:9001;
            fastcgi_index index.php;
            fastcgi_param SCRIPT_FILENAME

/var/www/blah/public_html$fastcgi_script_name;

            try_files $uri =403;
    }

}

Ignore the try_files and bogus return, they’re in place to try to trace
what’s happening where.

This is nginx 1.0.4, if it matters.

Basically, the problem is that the last try_files is triggered (I get a
403 requesting /subdir/index.php, and if I change that last try_files to
404 then I get a 404); Therefore I conclude the regex trying to catch
php files under /subdir is not effective.

What would the proper regex be ?
I want it to catch /subdir/.php, /subdir/subsub/.php,
/subdir/s/u/b.php, etc

On a related note, trying to access www.vhost.local/subdir (no trailing
/) results in nginx trying to serve subdir from the original root (ie
the alias isn’t picked up); It may be a trivial question but I’ve run
into this in the past. What is the correct way to catch both /subdir and
/subdir/ requests?

I would very much appreciate a reply on this subject, as I’ve been
struggling with this for hours. Regexes are not my strong point.

Thanks.

Posted at Nginx Forum:

2

Hello!

On Thu, Aug 11, 2011 at 04:22:52AM -0400, hugo wrote:

I have a virtual host, and for a certain subdirectory I want to use
another fastcgi backend.

What I have now goes something like:
(…)
location ~ /subdir/ {

Do you actually want to match prefix here, as opposed to any uri
containing “/subdir/” in it? If yes, use

     location /subdir/ {

instead. To prevent all other regexp locations from matching
under /subdir/ (even if there are no regexp locations in subdir
matched) you may also want to use “^~” (no regexp check on match),
i.e.

     location ^~ /subdir/ {

           alias /var/www/otheraccount/public_html/;

            # PHP FastCGI
            location ^~ /subdir\/(.+)\.php {

“^~” means “no regexp check on match”, you have to use “~” (regexp
location) here instead. And unless you really need captures here
for some reason not present in posted config, it’s enough to just
use .php pattern here. You may also need “$” anchor to make sure
you are matching extension but not some intermediate part of
name.

I.e. use

              location ~ \.php$ {

here instead.

   }

    # PHP FastCGI
    location ~ \.php {

The same as above: you probably need “$” anchor here.

      location ~ \.php$ {

Ignore the try_files and bogus return, they’re in place to try to trace
what’s happening where.

This is nginx 1.0.4, if it matters.

Basically, the problem is that the last try_files is triggered (I get a
403 requesting /subdir/index.php, and if I change that last try_files to
404 then I get a 404); Therefore I conclude the regex trying to catch
php files under /subdir is not effective.

See above. The problem is that you don’t have regexp but static
string, due to “^~” used.

What would the proper regex be ?
I want it to catch /subdir/.php, /subdir/subsub/.php,
/subdir/s/u/b.php, etc

Recommended pattern is:

location / {
    ...

    location ~ \.php$ {
        ...
    }
}

location /subdir/ {
    ...

    location ~ \.php$ {
        ...
    }
}

Note all top-level locations are just normal static strings with
prefix match (most specific match wins). Regexp locations are
properly isolated in them, and don’t interfere with processing of
requests in other locations.

On a related note, trying to access www.vhost.local/subdir (no trailing
/) results in nginx trying to serve subdir from the original root (ie
the alias isn’t picked up); It may be a trivial question but I’ve run

This is because “/subdir” isn’t matched by “location /subdir/”
(neither by “location ~ /subdir/”), and hence it’s processed in
some other matching location (usually “location /”, or implicit
location if you don’t have one defined).

into this in the past. What is the correct way to catch both /subdir and
/subdir/ requests?

I would recommend using something like

location = /subdir {
    root ...
    # or just immediate redirect to /subdir/, e.g
    # return 301 /subdir/;
}

location /subdir/ {
    root ...
}

Note that if you use

location /subdir/ {
    proxy_pass ...
}

nginx will automagically recognize that requests to “/subdir”
should be redirected to “/subdir/”, and you don’t need extra
“location = /subdir”. This applies only to locations fully
handled by backend modules though.

I would very much appreciate a reply on this subject, as I’ve been
struggling with this for hours. Regexes are not my strong point.

Don’t use regexp unless you really need to, use normal locations.
(This applies even if one have no problems with regexps.)

Maxim D.

3

hugo Wrote:

$fastcgi_script_filename includes /subdir, and the
path ends up as
/var/www/othervhost/public_html/subdir/target.php;
however target.php lives in the root folder,
below.

Short of using …/, what is the recommended
solution?

Actually …/ will lead nowhere, please disregard that.

Posted at Nginx Forum:

4

Hello,

Thanks for the reply. I’m getting somewhere now. Clearly a review of the
documentation regarding location is in order for me.

I’m stumped by something else now;

The fastcgi server returns a 404 for /subdir/target.php, because
$fastcgi_script_filename includes /subdir, and the path ends up as
/var/www/othervhost/public_html/subdir/target.php; however target.php
lives in the root folder, below.

Short of using …/, what is the recommended solution?

Posted at Nginx Forum:

5

I worked around this by adding a symlink [/var/www/othervhost/subir →
public_html]. Ideally I’d like to solve it at the webserver level, but
this will do too.

The location blocks provided before are working. Thank you.

Regards,

Hugo

Posted at Nginx Forum: