app/models/attachment.rb
class Attachment < ApplicationRecord
belongs_to :todo, touch: true
has_attached_file :file,
url: '/:class/:id/:basename.:extension',
path: ":rails_root/db/assets/#{Rails.env}/:class/:id/:basename.:extension",
override_file_permissions: 0660
do_not_validate_attachment_file_type :file
# validates_attachment_content_type :file, :content_type => ["text/plain"]
before_destroy :delete_attached_file
private
def delete_attached_file
file = nil
save!
end
end