server {
server_name example.com;
return 301 $scheme://www.example.com$request_uri;
}
server {
server_name "~^(?!www\.).*";
return 301 $scheme://www.$host$request_uri;
}
server {
server_name www.example.com;
return 301 $scheme://example.com$request_uri;
}
server {
server_name "~^www\.(.*)$";
return 301 $scheme://$1$request_uri;
}