Is it possible to loop over blocks in Nginx and use variables?

What I want to do is to replace the /locale/ part of the incoming URL with an equivalent query string. I want to do this in my reverse proxy which is Nginx.

Consider this Nginx code:

	include /etc/letsencrypt/options-ssl-nginx.conf;
ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem;
location /
{
proxy_pass http://localhost:3500;
}
location = /fa
{
proxy_pass http://localhost:3500;
rewrite ^/fa/(.*)$ /$1?locale=fa;
rewrite ^/fa /?locale=fa;
}
location /fa/
{
proxy_pass http://localhost:3500;
rewrite ^/fa/(.*)$ /$1?locale=fa;
rewrite ^/fa /?locale=fa;
}
location = /en
{
proxy_pass http://localhost:3500;
rewrite ^/en/(.*)$ /$1?locale=en;
rewrite ^/en /?locale=en;
}
location /en/
{
proxy_pass http://localhost:3500;
rewrite ^/en/(.*)$ /$1?locale=en;
rewrite ^/en /?locale=en;
}
location = /ar
{
proxy_pass http://localhost:3500;
rewrite ^/ar/(.*)$ /$1?locale=ar;
rewrite ^/ar /?locale=ar;
}
location /ar/
{
proxy_pass http://localhost:3500;
rewrite ^/ar/(.*)$ /$1?locale=ar;
rewrite ^/ar /?locale=ar;
}
location = /ru
{
proxy_pass http://localhost:3500;
rewrite ^/ru/(.*)$ /$1?locale=ru;
rewrite ^/ru /?locale=ru;
}
location /ru/
{
proxy_pass http://localhost:3500;
rewrite ^/ru/(.*)$ /$1?locale=ru;
rewrite ^/ru /?locale=ru;
}
location = /tr
{
proxy_pass http://localhost:3500;
rewrite ^/tr/(.*)$ /$1?locale=tr;
rewrite ^/tr /?locale=tr;
}
location /tr/
{
proxy_pass http://localhost:3500;
rewrite ^/tr/(.*)$ /$1?locale=tr;
rewrite ^/tr /?locale=tr;
}

As you can see, a lot of code is repetitive. This includes the location block and the regex and the proxy_pass directive, etc. I want to be able to DRY this part.

Basically, this part is getting repeated for each locale:

	location = /tr
{
proxy_pass http://localhost:3500;
rewrite ^/tr/(.*)$ /$1?locale=tr;
rewrite ^/tr /?locale=tr;
}
location /tr/
{
proxy_pass http://localhost:3500;
rewrite ^/tr/(.*)$ /$1?locale=tr;
rewrite ^/tr /?locale=tr;
}

Is there a way to loop over locales and not repeat this section?

The rewrite statements can capture the locale in the regular expression, for example:

rewrite ^/(\w\w)/(.*)$ /$2?locale=$1 break;
rewrite ^/(\w\w)$ /?locale=$1 break;

Use a regular expression to select any URI with a locale, for example:

location ~ ^/(fa|en|ar|ru|tr)(/|$) { ... }

Or more generally (if this works for you):

location ~ ^/\w\w(/|$) { ... }

Example:

location / {
proxy_pass http://localhost:3500;
}
location ~ ^/\w\w(/|$) {
rewrite ^/(\w\w)/(.*)$ /$2?locale=$1 break;
rewrite ^/(\w\w)$ /?locale=$1 break;
proxy_pass http://localhost:3500;
}