how to return selected data on json api

Question

i have created API i have two tables users and addresses i want only return state and city in seperate array how is it ?

    my controller  
           def show
             @address = Address.where(user_id:params[:id])
             render json: @address        
           end
 My postman output
       https://imgur.com/a/t5xHYBI
    #my expected output
     [
            { 
                "city": "palani",
                "city": "coimbatore",

            },
            {
                "state": "tamilnadu",
                "state": "tamilnadu",            
            }
        ]

Answer 1

You will have to understand about JSON builders,

start here https://www.ruby-toolbox.com/categories/API_Builders

Choose one and get along .

I have used Jbuilder quite a few times

Answer 2

create json-jbuilder view

app/[controller]/show.json.jbuilder

json.id address.id
json.user_id address.user_id
json.city address.city
...

your controller action

   def show
     @address = Address.where(user_id:params[:id])       
   end

for more details you may read jBuilder documentation https://github.com/rails/jbuilder