Hashes in params

gistfile1.txt

# Hash in params
def product_params
  properties_keys = params[:product].try(:fetch, :properties, {}).keys
  params.require(:product).permit(:title, :description, properties: properties_keys)
end

# Nested hash in params
def item_params
  params.require(:item).permit(values: permit_recursive_params(params[:item][:values]))
end

def permit_recursive_params(params)
  params.map do |key, value|
    if value.is_a?(Array)
      { key => [ permit_recursive_params(value.first) ] }
    elsif value.is_a?(Hash) || value.is_a?(ActionController::Parameters)
      { key => permit_recursive_params(value) }
    else
      key
    end
  end
end