strong parameters permit all attributes for nested attributes

Question

Is there a way in strong parameters to permit all attributes of a nested_attributes model? Here is a sample code.

class Lever < ActiveRecord::Base  has_one :lever_benefit  accepts_nested_attributes_for :lever_benefit end  class LeverBenefit < ActiveRecord::Base   # == Schema Information   #  id          :integer          not null, primary key   #  lever_id    :integer   #  explanation :text end 

For lever strong parameters i am writing currently this

def lever  params.require(:lever).permit(:name,:lever_benefit_attributes => [:lever_id, :explanation]) end 

Is there a way for nested attributes i can write to permit all attributes without explicitly giving the attributes name like lever_id and explanation ?

Note: Please don't get confused with this question with permit! or permit(:all) this is for permitting all for nested attributes

Answer 1

The only situation I have encountered where permitting arbitrary keys in a nested params hash seems reasonable to me is when writing to a serialized column. I've managed to handle it like this:

class Post   serialize :options, JSON end  class PostsController < ApplicationController   ...    def post_params     all_options = params.require(:post)[:options].try(:permit!)     params.require(:post).permit(:title).merge(:options => all_options)   end end 

try makes sure we do not require the presents of an :options key.

Answer 2

Actually there is a way to just white-list all nested parameters.

params.require(:lever).permit(:name).tap do |whitelisted|   whitelisted[:lever_benefit_attributes ] = params[:lever][:lever_benefit_attributes ] end 

This method has advantage over other solutions. It allows to permit deep-nested parameters.

While other solutions like:

nested_keys = params.require(:lever).fetch(:lever_benefit_attributes, {}).keys params.require(:lever).permit(:name,:lever_benefit_attributes => nested_keys) 

Don't.

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Source:

https://github.com/rails/rails/issues/9454#issuecomment-14167664