rails cannot pass nested hash to controller params

Question

Since I am using Rspec to test whether my controller is working fine, I did things below:

in test_rspec.rb,

before do
  params = {
    date_begin: "2018-10-01", 
    date_end: "2018-10-05", 
    options: {country_code: "US"}
  }

  get :index, params: params, as: :json
end

it do
  expected(response).to have_http_response(200) }
end

in test_controller.rb,

def index
  puts params_checker
  render json: Test.report(params_checker[:date_begin], 
                           params_checker[:date_end],
                           params_checker[:options])
end

private
  def params_checker
    params.permit(:date_begin, :date_end, :options)
  end

when I run code with rspec command, there goes something wrong, the parameter with nested hash :options is gone! below is the output of params in terminal & some of its error info:

> {"date_begin"=>"2018-10-01", "date_end"=>"2018-10-03"}
> ArgumentError:
   wrong number of arguments (given 3, expected 2)

I search everywhere on internet and tried some of the solutions but it won`t help. I do know this error is caused by parameter missing. Could any one help me finger it out why hashes cannot be passed to controller`s params in my case?

note : I am using rails 5.1.6

Answer 1

After searching for lots of solutions, I got one clear way to handle it. Strong parameters handling helped me a lot.

First, if you want to pass an array or hash, whatever the parameter is, only if it is a nested parameter, you should claim it inside the params.permit() statement, and add what key is allowed to pass in [] , because permit only allows scalar values to pass, and filter hashes and arrays by default if the specific parameter is not claimed. code as below:

private
  def stat_params
    params.permit(:date_begin, :date_end, options: [:country_code])
  end

Second, when using Rspec to test the controller, nested parameters will be passed as <ActionController::Parameters:xxxx> type, so you have to add to_unsafe_h statement to this specific parameter, as below:

def index
  render json: Test.report(stat_params[:date_begin],
                           stat_params[:date_end],
                           stat_params[:options].to_unsafe_h)
end

This works fine for me finally.