Unless you need to have both an nginx config and a apache config at the same time you can just use attribute and override it from your environment file.

Default['cluster']['endpoint'] = ''
In your environment file just do this to override the value, the name of the attribute doesn't really matter so much just the value of the attribute.
Override['cluster']['endpoint'] = 'new value'

You can also do

Default['cluster']['endpoint'] = node['cluster']['nginx']['endpoint']

To set the value of the cluster endpoint value to that of the nginx endpoint value.

---