Rails 4 enum validation

Question

This is the first time I'm using enums with rails 4 and I ran into some issues, have couple of dirty solutions in mind and wanted to check are there any more elegant solutions in place :

This is my table migration relevant part:

create_table :shippings do |t|
  t.column :status, :integer, default: 0
end

My model:

class Shipping < ActiveRecord::Base
  enum status: { initial_status: 0, frozen: 1, processed: 2 }
end

And I have this bit in my view (using simple form for) :

= f.input :status, :as => :select, :collection => Shipping.statuses, :required => true, :prompt => 'Please select', label: false

So in my controller:

  def create
    @shipping = Shipping.create!(shipping_params)

    if @shipping.new_record?
      return render 'new'
    end

    flash[:success] = 'Shipping saved successfully'
    redirect_to home_path
  end

private

  def shipping_params
    params.require(:shipping).permit(... :status)
  end

So when I submit create form and the create action fire I get this validation error :

'1' is not a valid status

So I thought I knew that the issue was data type so I added this bit in the model :

before_validation :set_status_type

  def set_status_type
    self.status = status.to_i
  end

But this didn't seem to do anything, how do I resolve this ? Has anyone had the similar experience?

Answer 1

You can find the solution here.

Basically, you need to pass the string ('initial_status', 'frozen' or 'processed'), not the integer. In other words, your form needs to look like this:

<select ...><option value="frozen">frozen</option>...</select>

You can achieve this by doing statuses.keys in your form. Also (I believe) you don't need the before_validation.

Optionally, you could add a validation like this:

validates_inclusion_of :status, in: Shipping.statuses.keys

However, I'm not sure that this validation makes sense, since trying to assign an invalid value to status raises an ArgumentError (see this).