proxy_cache_path /home/my_user/cache levels=1:2 keys_zone=my_key:5m max_size=500m inactive=10d;
  server {
    listen   80;
    # [............]


    location / {
      secure_link $arg_h, $arg_t;
      secure_link_md5 "$secure_link_expires$uri$arg_u my_secret";

      proxy_temp_path /home/my_user/tmp;
      proxy_cache my_cache;
      proxy_cache_key $uri;

      # [............]

location / {
      secure_link $arg_h, $arg_t;
      secure_link_md5 "$secure_link_expires$uri$arg_u my_secret";

      # [skipped]

      set $real_cached_file_name ???????

/imgs/test_image1.jpg

/data/nginx/cache/a/15/af54470326835257815a