Service Gateway in nginx

service_gateway.conf

upstream fire {
  server localhost:8081;
}

upstream warehouse  {
  server localhost:8082;
}

upstream authority  {
  server localhost:8083;
}

server {
  location ~ ^/api/(instances/buckets)/? {
    rewrite ^/api(.*)$ $1 break;  
    proxy_pass http://fire;
  }

  location ~ ^/api/(repositories)/? {
    rewrite ^/api(.*)$ $1 break;  
    proxy_pass http://warehouse;
  }

  location ~ ^/api/(users/keys/permissions)/? {
    rewrite ^/api(.*)$ $1 break;  
    proxy_pass http://authority;
  }
}