ActionParamsPermitter

Strong Parameters are the great idea to keep your models clean. But what about controllers when form is very complex and params.require(:anything).permit! does not helps?

class AnyController
  private

  def permitted_params
    params.permit tutorial: [
      :cost, :hours, :minutes, :seconds,
      steps_attributes: [:id, :description, :order_number, :_destroy],
      tool_ids: [],
      material_ids: [],
      post_attributes: [
        :id, :title, :description, :meta_title, :meta_description,
        :feature, :user_id, tag_list: [], category_ids: []],
        media: [:id, :title, :alt, :_destroy]
    ]
  end

end

This code seems not so clean.

action_params_permitter gives you a alternative way to do permitting more clean.

Installation

Add this line to your application's Gemfile:

gem 'action_params_permitter', github: 'alterego-labs/action_params_permitter'

And then execute:

$ bundle

Usage

In general provided DSL looks like follow:

SomePermitter = ActionParamsPermitter::Base.new do
  # Your specific rules
end

Rules are predefined and their variation are listed below:

1. resource
2. attribute
3. attributes

Nesting is allowed but only for resource (which is quite logical). There are some statements about resource rule:

1. Top level resource always must accepts nestings rules otherwise exception will be raised.
2. Top level resource may be required, but only one otherwise exception will be raised.
3. Nested resource may not accepts nestings rules.

Lets define permitter for our example in the top of readme:

TutorialsParamsPermitter = ActionParamsPermitter::Base.new do
  resource :tutorial do
    attributes :cost, :hours, :minutes, :seconds
    resource :steps_attributes do
      attributes :id, :description, :order_number, :_destroy
    end
    resource :tool_ids
    resource :material_ids
    resource :post_attributes do
      attributes :id, :title, :description, :meta_title, :meta_description
      attributes :feature, :user_id
      resource :tag_list
      resource :category_ids
    end
    resource :media do
      # Written specially for showing `attribute` rule in work
      attribute :id
      attribute :title
      attribute :alt
      attribute :_destroy
    end
  end
end

TutorialsParamsPermitter respond to #permit(params) method. And now we may refactor our controller's method like this:

class AnyController
  private

  def permitted_params
    TutorialsParamsPermitter.permit(params)
  end
end

You may define root resource as required like this:

TutorialsParamsPermitter = ActionParamsPermitter::Base.new do
  resource :tutorial, required: true do
    ...
  end
end

Usage with Form Object gems

There are many gems providing form objects, for example reform. And if you use a such one action_params_permitter is not helps you. Form Object gems inside carries same functional and action_params_permitter usage is excessive.

What about like params.require(:any_resource).permit!?

Notice, please, this gem was written only for complex params permitting. Usage for so simple example is excessive.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/alterego-labs/action_params_permitter. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

License

The gem is available as open source under the terms of the MIT License.