Mapping model filed to document field


I have to design on my web app a list of linked "drop down list" from a document saved into my ES database. Therefore i've create a document containing all the values of my drop down lists'.
Let's say called

"section","class", "subclass", "group", "subgroup"
A 01 19 B 01
A 01 20 B 01
B 01 12 C 02

These list are dependent, each one from the previous one!(apart from section that is indipendent)

I need to map MyModel"model_section" field to my document field "section" to retrieve all the distinc value from this field. How can i get it?
Possibly i would map another model field "model_class" to my document "class" field retrieveing all distinct value from that field based on the value chosen for "section".

Is this doable with elasticsearch? How can i do it?

Thanx valerio

Sorry, i think this is not the right forum to ask for this question.