Specific fpm pool for a subdirectory - nginx

Question

I'm trying to keep my nginx.conf simple but I'm having trouble getting a specific folder's .php files to use a different fpm than the global one.
My current configuration is
location ~ \.php$ {
# Test for non-existent scripts or throw a 404 error
# Without this line, nginx will blindly send any request ending in .php to php-fpm
try_files $uri =404;
include /etc/nginx/fastcgi.conf;
fastcgi_pass unix:/run/php-fpm.socket;
}
location /postfixadmin/ ~ \.php$ {
# Test for non-existent scripts or throw a 404 error
# Without this line, nginx will blindly send any request ending in .php to php-fpm
try_files $uri =404;
include /etc/nginx/fastcgi.conf;
fastcgi_pass unix:/run/php-fpm.vmail.socket;
}
I'm trying to get the sub folder postfixadmin (and below) to use the /run/php-fpm.vmail.socket when it comes to .php files, but otherwise globally across all other sites, use /run/php-fpm.socket. Is it possible to apply this special rule to only a single sub folder?
Unfortunately this breaks nginx and it won't load. I've tried other configs but no matter what I've tried so far just ends up either not loading or using the global socket instead.

Answer 1

Try this as second location:
location ~ /postfixadmin/.*\.php$ {
...
}
Or you can try nested location:
location ~ \.php$ {
location ^/postfixadmin/ {
try_files $uri =404;
include /etc/nginx/fastcgi.conf;
fastcgi_pass unix:/run/php-fpm.vmail.socket;
}
try_files $uri =404;
include /etc/nginx/fastcgi.conf;
fastcgi_pass unix:/run/php-fpm.socket;
}