Disable strong parameters for a specific action

Question

I have a serious problem with strong parameters. Its working pretty well in my about 200 actions but in one it doesn't because I'm working very dynamic with the parameters there and I also cant change it because of the applications design.

So I want to disable strong parameters validation in just this specific action. Is there a way to do this?

Answer 1

Strong parameters overrides the params method in ActionController::Base. You can simply override it and set it back to what you want yourself.

So this:

class MyController < ApplicationController
  def params
    request.parameters
  end
end

Will effectively disable strong parameters for all actions in your controller. You only wanted to disable it for a particular action though so you could do that with:

class MyController < ApplicationController
  before_action :use_unsafe_params, only: [:particular_action]

  def params
    @_dangerous_params || super
  end

  def particular_action
    # My params is unsafe
  end

  def normal_action
    # my params is safe
  end

  private

  def use_unsafe_params
    @_dangerous_params = request.parameters
  end
end

Answer 2

Not too sure if this is best practice but for Rails 5 I just use request.params instead of params anytime I want to skip strong params.

So instead of something like:

post = Post.new(params[:post])

I use:

post = Post.new(request.params[:post])