how to append data to json in ruby/rails?

Question

Say i have this short code:

item = Item.find(params[:id])
render :json => item.to_json

but i needed to insert/push extra information to

Answer 1

How to append data to json in ruby/rails 5

If you use scaffold, e.g.:

rails generate scaffold MyItem

in the view folder you will see next files:

app/view/my_item/_my_item.json.jbuilder
app/view/my_item/index.json.jbuilder

so, you can add custom data to json output for an item, just add this:

json.extract! my_item, :id, :some_filed, :created_at, :updated_at
json.url my_item_url(my_item, format: :json)    

json.my_data my_function(my_item)

As you can see, it's possible to modify as one item json output, as index json output.