Split Test Load Balancer Nginx Configuration

config

map $split_test_cookie_name $split_test_cookie {
  default $cookie_split_test_version;
}
 
upstream app.com {
  server old.app.com;
}
 
split_clients "app${remote_addr}${http_user_agent}${date_gmt}" $upstream_variant {
  10% "test";
  * "original";
}
 
map $split_test_cookie $upstream_group {
  default    $upstream_variant;
  "test"     "test";
  "original" "original";
}
 
geo $internal_request {
  ranges;
  4.3.2.1-4.3.2.254 1;
  default 0;
}
 
server {
  listen 80 default_server;
  listen [::]:80 default_server ipv6only=on;
  server_name app.com www.app.com;
 
  set $split_test_cookie_name "split_test_version";
 
  location = / {
    add_header Set-Cookie "${split_test_cookie_name}=$upstream_group;Path=/;Max-Age=518400;";
 
    set $test_group 0;
 
    if ($upstream_group = "test") {
      set $test_group 1;
    }
 
    if ($internal_request = 1) {
      set $test_group 0;
    }
 
    if ($test_group = 1) {
      return 302 http://new.app.com/;
      break;
    }
 
    proxy_pass http://app.com;
  }
 
  location / {
    proxy_pass http://app.com;
  }
}