Permissions

A small library for adding permissions to an application for authorization.

Installation

gem install permissions

Usage

API

for(*keys, &block): Creates a permission with the given block for each key.

authorize?(key, *args): Runs permission block for key with args.

deep_dup: Copies permissions to a new object.

Authorizable

permissions: Must be implemented by your application.

authorize_for?(key, *args) Based off the implemented permissions, calls block with args for the given key.

Example

require 'permissions'

class User
  include Permissions::Authorizable

  def initialize(permissions)
    @permissions = permissions
  end

  # Authorizables must provide their own implementation of "permissions".
  # An attr_reader would do.
  def permissions
    @permissions
  end
end

class Command
  attr_reader :user

  def initialize(user)
    @user = user
  end

  # Not provided by the library. An advanced example
  # on how to authorize things like: "Does an object
  # belong to a particular user?"
  def authorize?(other)
    other.authorize_for?(self.class, self)
  end
end

permissions = Permissions.new

permissions.for(Command) { |user, command| user == command.user }

user = User.new(permissions)

command = Command.new(user)

command.authorize?(user) # true

More examples can be found by in the tests.