etcd: etcd can't advertise URLs with paths, and therefore can't be run behind an HTTP proxy using location directives

In my application, I would like to run etcd (particularly the peer URLs) behind an Nginx proxy. The primary reason I want to do this is that operators are already instructed to open port 443; I don’t want to require the opening of additional ports on my application. A secondary reason is to handle SSL termination and SSL mutual auth in Nginx, since there are more configuration options there.

Therefore, what I want to do is create location directives in nginx such as /etcd/client and /etcd/peer. Each of these locations will proxy to the local etcd instance which is listening 127.0.0.1 and the standard ports. For example:

location /etcd/peer {
  if ($ssl_client_verify != SUCCESS) {
    return 401;
  }

  rewrite /etcd/peer/(.*) /$1 break;
  proxy_pass http://localhost:2380;
}

After configuring nginx, the next step is to start the etcd servers, each of which will advertise the Nginx URL, like so : --initial-advertise-peer-urls https://host-01.app/etcd/peer.

Unfortunately, pkg/types/urls.go does not permit URLs with paths. Therefore, my configuration is not accepted by etcd.

Is there a particular reason why advertise-peer-urls is not allowed to contain a path?