Gatekeeper

Gatekeeper is a Rails engine for MongoDB which adds two simple functionalities:

Model methods to control which informations can be seen by a specific user.
Controller concern to handle HTML, JS and JSON responses.

Installation

Add this line to your application's Gemfile:

gem 'gatekeeper'

And then execute:

$ bundle install

Usage

Models

The first basic use is to define a model for your application and the information that can be accessed.

# app/models/book.rb
class Book

  include Mongoid::Document

  field   :name,          type: String
  field   :internal_id,   type: Integer

  allowed_info do |user|
    case user.role
    when :librarian
      [ :name, :internal_id ]
    when :customer
      [ :name ]
    end
  end

end

# app/models/user.rb
class User

  include Mongoid::Document

  field   :name,          type: String
  field   :role,          type: Symbol

end

When accessing the model info:

book = Book.new(name: 'Lord of the Rings', internal_id: 1234567)
librarian = User.new(name: 'Tony', role: :librarian)
customer = User.new(name: 'Bob', role: :customer)

book.info               # { :name => "Lord of the Rings", :internal_id => 1234567 }
book.info(librarian)    # { :name => "Lord of the Rings", :internal_id => 1234567 }
book.info(customer)     # { :name => "Lord of the Rings" }

Controllers

On controllers, you can include Gatekeeper::Responder to generate automatic responses for your HTML, JS, or JSON views. These responses contains information based on the allowed_info method specified in your models.

License

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