At matestack, we have had good experiences using matestack with Pundit. CanCanCan, another very popular authorization library in Rails, is also supported, as shown below!

Both Pundit and CanCanCan use pure Ruby and focus on the model and controller layer, so they are compatible to matestack's UI library.

Example 1: Pundit

Here we see how Pundit defines policies and we can check for them in the controller action, just before matestack's responder_for!

A Pundit example in app/policies/user_policy.rb:

class UserPolicy
  attr_reader :user
​
  def initialize(user)
    @user = user
  end
​
  def show?
    user.is_visible?
  end
​
end

Matestack's app/controllers/user_controller.rb:

class UserController < ApplicationController
​
  matestack_app UserApp
​
  def show
    @user = User.find_by(id: params[:id])
    authorize @user # checking Pundit policy
    render UserApp::Pages::Show # matestack page responder
  end
​
end

Example 2: CanCanCan

Here we see how CanCanCan defines abilities and we can check for them in the controller action, just before matestack's responder_for!

CanCanCan's app/models/ability.rb example, borrowed from their guides:

class Ability
  include CanCan::Ability
​
  def initialize(user)
    can :read, :all # permissions for every user, even if not logged in    
    # [...]
  end
​
end

Matestack's app/controllers/user_controller.rb:

class UserController < ApplicationController
​
  matestack_app UserApp
​
  def show
    @user = User.find_by(id: params[:id])
    authorize! :read, @user # checking for CanCanCan ability
    render UserApp::Pages::Show # matestack page responder
  end
​
end