nginx cors allow origins #course #book

nginx.conf

// See https://nginx.org/en/docs/http/ngx_http_map_module.html
// This sets the value of $cors_header depending on the value of $http_origin
map $http_origin $cors_header{
  default "";
  "~^(https:\/\/safedomain\.com)$" "$http_origin";
  "~^(https:\/\/anotherdomain\.com)$" "$http_origin";
}

server {
  listen 80;
  listen [::]:80;

  // we include the value of $cors_header which we set to the value 
  // of the http origin we want to allow
  add_header 'Access-Control-Allow-Origin' "$cors_header";

  // ... remaining CORS headers and server body continue ... 
}