CORS on NGINX

cors.conf

# https://enable-cors.org/server_nginx.html

server {
    listen       80;
    server_name  localhost;

    #charset koi8-r;
    #access_log  /var/log/nginx/host.access.log  main;

    root   /usr/share/nginx/html;
    index  index.html index.htm;

    location ~* "^/storage/(?<att>.+\.pdf)$" {
        alias /usr/share/nginx/html/$att;

        expires 1y;
        add_header Cache-Control "public";

        # Adiciona permissão de CORS para permitir pre-visualização no browser
        # add_header Access-Control-Allow-Origin *;

        # add_header Content-disposition "attachment";

        if ($request_method = 'OPTIONS') {
            add_header 'Access-Control-Allow-Origin' '*';
            add_header 'Access-Control-Allow-Methods' 'GET,POST,OPTIONS';
            #
            # Custom headers and headers various browsers *should* be OK with but aren't
            #
            # add_header 'Access-Control-Allow-Headers' 'DNT,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Range';
            #
            # Tell client that this pre-flight info is valid for 20 days
            #
            add_header 'Access-Control-Max-Age' 1728000;
            add_header 'Content-Type' 'text/plain; charset=utf-8';
            add_header 'Content-Length' 0;

            # add_header 'Content-Disposition' 'filename="$att"';

            return 204;
        }

        if ($request_method = 'GET') {
            add_header 'Access-Control-Allow-Origin' '*';
            add_header 'Access-Control-Allow-Methods' 'GET,POST,OPTIONS';
            add_header 'Access-Control-Allow-Headers' 'DNT,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Range';
            add_header 'Access-Control-Expose-Headers' 'Content-Length,Content-Range,Content-Disposition';

            add_header 'Content-Disposition' 'filename="$att"';
        }
    }


    # location / {
    #     add_header Access-Control-Allow-Origin *;
        
    #     root   /usr/share/nginx/html;
    #     index  index.html index.htm;
    # }

    #error_page  404              /404.html;

    # redirect server error pages to the static page /50x.html
    #
    error_page   500 502 503 504  /50x.html;
    location = /50x.html {
        root   /usr/share/nginx/html;
    }

    # proxy the PHP scripts to Apache listening on 127.0.0.1:80
    #
    #location ~ \.php$ {
    #    proxy_pass   http://127.0.0.1;
    #}

    # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
    #
    #location ~ \.php$ {
    #    root           html;
    #    fastcgi_pass   127.0.0.1:9000;
    #    fastcgi_index  index.php;
    #    fastcgi_param  SCRIPT_FILENAME  /scripts$fastcgi_script_name;
    #    include        fastcgi_params;
    #}

    # deny access to .htaccess files, if Apache's document root
    # concurs with nginx's one
    #
    #location ~ /\.ht {
    #    deny  all;
    #}
}