Nginx: directly return $remote_addr in text/plain

Question

It may sound like a code golf question, but what is the simplest / lightest way to return $remote_addr in text/plain?

So, it should return several bytes of the IP address in a plain text.

216.58.221.164

Use case: An API to learn the client's own external (NAT), global IP address.

Is it possible to do it with Nginx alone and without any backends? If so, how?

Answer 1

The simplest way is:

location /remote_addr {
    default_type text/plain;
    return 200 "$remote_addr\n";
}

No need to use any 3rd party module (echo, lua etc.)

Answer 2

Use ngx_echo:

location /ip {
    default_type  text/plain;
    echo $remote_addr;
}

Use ngx_lua:

location /b {
    default_type  text/plain;
    content_by_lua '
        ngx.say(ngx.var.remote_addr)
    ';
}