MayI

A nice explicit API for activity based authorization. Having the authorization question clearly writen out.

In short

Role based authorization

if user_object.is_admin?
  ...
end

Activity based authorization

access.may_add_user! do
  ...
end

As you can see with MayI this changes to a nice method call with an explicit mening. I have found this small API to be a big win! Now we have the actually question we want answered documented.

The API

A basic access rights implementation.

class MyAccessHandler

  include MayI
  
  def initialize(user)
    @user = user
  end
  
  def may_view_secret_stuff(stuff)
    stuff.owner_id ==  @user.id
  end
  
  def may_create_new_record
    @user.type == "admin"
  end
end

This is how you would use it.

access = MyAccessHandler.new(user)

# Simple boolean
if access.may_create_new_record?
  ...
end

# With a block
access.may_create_new_record? do
  ...
end

# With erros
access.may_view_secret_stuff!(stuff)
access.may_view_secret_stuff!(stuff) do
  ...
end

# With custom error message
access.error_message("A custom error message").may_view_secret_stuff!(stuff)

With Rails

class ApplicationController < ActionController::Base

  helper_method :current_user
  def current_user 
    ...
  end
  
  helper_method :access
  def access
    @@access_cache ||= MyAccessHandler.new(current_user)
  end
  
end

class StuffController < ApplicationController

  def show
    stuff = Stuff.find(params[:id])
    
    access.may_view_secret_stuff?(stuff) do
      ...
    end
  end
  
end

Contributing to MayI

• Check out the latest master to make sure the feature hasn't been implemented or the bug hasn't been fixed yet.
• Check out the issue tracker to make sure someone already hasn't requested it and/or contributed it.
• Fork the project.
• Start a feature/bugfix branch.
• Commit and push until you are happy with your contribution.
• Make sure to add tests for it. This is important so I don't break it in a future version unintentionally.

Copyright

Copyright (c) 2012-2015 Darwin. See LICENSE.txt for further details.