Redirect user on logout to login page of the same app

Unfortunately this doesn't seem to work - can it be because we're using a location with directory_index?

Our Shiny Server config file looks like so:

server {
  listen 3838 0.0.0.0;

  #Serve index for navigating between apps
  location / {
    site_dir /srv/shiny-server/index;
    log_dir /var/log/shiny-server/index;
    directory_index on;
    required_user *;
  }

  #Apps
  location /app1{
    app_dir /srv/shiny-server/prod/app1;
    log_dir /var/log/shiny-server/app1;
    required_user *;
  }

  location /app2{
    app_dir /srv/shiny-server/prod/app2;
    log_dir /var/log/shiny-server/app2;
    required_user *;
  }
}