Checking values of hash before show in jbuider , Ruby on Rails

Question

I have a jbuilder to show my object.

Thats how it looks (part of it)

o = @property_object

json.features o.property_object_feature_pack, :pool, :garage, terrace

and this showing me next:

{
 features: {
  pool: {
   params: null,
   present: "false"
   },
  garage_parking: {
   params: null,
   present: "false"
   },
  terrace_balcony: {
   params: null,
   present: "true"
   }
 }
}

Question is that I don't want to show in output features with present: "false" . To solve this I write next code

json.features o.property_object_feature_pack, :pool if o.property_object_feature_pack.pool['present'] === "true"
json.features o.property_object_feature_pack, :garage_parking if o.property_object_feature_pack.garage_parking['present'] === "true"
json.features o.property_object_feature_pack, :terrace_balcony if o.property_object_feature_pack.terrace_balcony['present'] === "true"

And it works - but looks awful. How it can be refactored?

Next problem that it can be new features to be added in ActiveRecord in future, and I want to know can we iterate over o.property_object_feature_pack without setting names ? (:pool, :garage_parking etc.. )

ps. raw o.property_object_feature_pack

features: {
 id: 820,
 property_object_id: 56879,
 created_at: "2015-04-27T18:25:25.712Z",
 updated_at: "2015-04-27T18:25:25.712Z",
 pool: {
  params: null,
  present: "false"
 },
 garage_parking: {
  params: null,
  present: "false"
 },
 terrace_balcony: {
  params: null,
  present: "true"
 },
 av_apartments: {
  params: null,
  present: "false"
 }
}

Updated

Inspired by #mudasobwa I had create a little helper method that solves my question

def features_list
    @property_object.property_object_feature_pack.as_json.select! do |_, v|
      v.is_a?(Hash) && v['present'] == 'true'
    end
  end

Answer 1

I have no clue about what jbuilder is, but I would suggest to convert json into plain ruby hash, do whatever you want and convert it back into json:

require 'json'
hash = JSON.parse what_you_got_from_builder
hash[:features].select! do |_, v| 
  !v.is_a?(Hash) || v[:present] == 'true' 
end
hash.to_json