nginx include config to enable cors to domains and subdomains in LA sites

sample of etc-nginx-conf.d-cors file

# Use with 
# include /etc/nginx/conf.d/cors;
# in your locations

# Allow static fonts 
location ~* .(eot|otf|svg|ttf|woff|woff2)$ {
  add_header Access-Control-Allow-Origin *;
}

set $cors '';

# Edit this regexp with your sub/domains 
# Test your regexp of type PCRE with a tool like https://www.regextester.com/
if ($http_origin ~* '^https?:\/\/(localhost|l-a\.site|.*\.l-a\.site)') {
  set $cors 'C';
}

# As multiple ifs are not allowed we follow this option
# http://rosslawley.co.uk/archive/old/2010/01/04/nginx-how-to-multiple-if-statements/

if ($request_method = GET) {
  set $cors '${cors}GET';
}

if ($request_method = POST) {
  set $cors '${cors}POST';
}

if ($request_method = OPTIONS) {
  set $cors '${cors}OPTIONS';
}

# This is modified version of: https://enable-cors.org/server_nginx.html restricting to previous regexp

if ($cors = COPTIONS) {
  add_header 'Access-Control-Allow-Origin' '*';
  add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
  #
  # Custom headers and headers various browsers *should* be OK with but aren't
  #
  add_header 'Access-Control-Allow-Headers' 'DNT,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Range';
  #
  # Tell client that this pre-flight info is valid for 20 days
  #
  add_header 'Access-Control-Max-Age' 1728000;
  add_header 'Content-Type' 'text/plain; charset=utf-8';
  add_header 'Content-Length' 0;
  return 204;
}
if ($cors = CPOST) {
  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';
}
if ($cors = CGET) {
  add_header 'Access-Control-Allow-Origin' '*' always;
  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';
}