Nginx to host app in different location [closed]

Question

I'm trying to serve CachetHQ in nginx + php-fpm in a specific location. The docs gives this as example that serves in status.example.com (which works):

server {
    listen 80;
    server_name status.example.com;

    root /var/www/Cachet/public;
    index index.php;

    location / {
        try_files $uri /index.php$is_args$args;
    }

    location ~ \.php$ {
         include fastcgi_params;
         fastcgi_pass 127.0.0.1:9000;
         fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
         fastcgi_index index.php;
         fastcgi_keep_conn on;
    }
}

However, instead of serving in status.example.com, I would like to serve in example.com/status.

I was expecting that this would work, but from error.log I see it's trying /etc/nginx/htmlindex.php, but it should be /mnt/data/site/www-cachet/public/index.php:

location /status/ {
    index index.php;
    root /mnt/data/site/www-cachet/public;

    try_files $uri index.php$is_args$args;

    location ~ ^/status/.+\.php$ {
        root /mnt/data/site/www-cachet/public;
        include fastcgi_params;
        fastcgi_pass   unix:/tmp/php-fpm.sock;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
        fastcgi_index index.php;
        fastcgi_keep_conn on;
    }
}

Answer 1

Let me start with the original configuration that you claim works, and try to modify it for your requirements, results below:

location ^~ /status {
    alias /var/www/Cachet/public;
    index index.php;

    location = /status {
        return 302 /status/;
    }
    location / {
        try_files $uri /status/index.php$is_args$args;
    }

    location ~ \.php$ {
         include fastcgi_params;
         fastcgi_pass 127.0.0.1:9000;
         rewrite ^/status/(.*) /$1;
         rewrite ^(.*)/ $1/index.php; # who knows what fastcgi_index is for?
         fastcgi_param SCRIPT_FILENAME $document_root$uri;
         fastcgi_keep_conn on;
    }
}

Basically, you want to use alias instead of root here, and probably also have an absolute path in the final try_files as well. I don't think adding extra prefixes within nested locations is needed, but you might want to make sure that the root location is a final match with the ^~ modifier.

The main trick, I guess, is that even with the alias directive things aren't as dandy as with a proper root, so, you have to make sure that the SCRIPT_FILENAME is set correctly. This part doesn't seem to be documented very clearly, and I'm too lazy to test out whether $fastcgi_script_name ngx variable and fastcgi_index directive play nice with alias -- instead of trying to determine how those work (or not), we simply do a couple of rewrite rules as applicable, and construct SCRIPT_FILENAME based on the results of our rewrite rules instead. :-)

However, with that said, I'd think the second rewrite rule (as well as the fastcgi_index it replaces) might as well be a no-op, because how were we supposed to end up in a \.php$ location if $uri didn't end in .php already? (Likewise, you're free to try to remove the first rewrite rule, too, and replace $uri in SCRIPT_FILENAME with $fastcgi_script_name, and see if things still work, but the internet from 2009 may indicate that they didn't.)