How to submit an array of integers in a Rails form?

Question

I would like to know if there is a way to have some sort of input field in a Rails form, so that if the user enters 1, 2, 3, then params[:model][:attribute] returns [1, 2, 3] or at least ['1', '2', '3'], but not ['1, 2, 3'].

Background:

I have a model Foo, which has an attribute bar_ids. The datatype of this attribute in the PostgresQL database is Array. I've tried several things:

• if f.text_field :bar_ids then params[:foo][:bar_ids] returns '1, 2, 3'
• if f.text_field_tag 'foo[bar_ids][]' then params[:foo][:bar_ids] returns ['1, 2, 3']
• if f.number_field :bar_ids then params[:foo][:bar_ids] returns '1' if I input only 1 and the form does not allow to input multiple numbers

So, again my question - is there a way to construct my form in such a way, so that Rails automatically parses the input to the respective datatype, in my case - an array of integers?

Answer 1

People usually edit the params manually before updating the model:

 params[:model][:attribute] = params[:model:][:attribute].split(',')
 # ...
 Model.update_attributes(params[:model])

It is usually done in controller action or in before_action.