ruby on rails - I'm struggling to understand how to use Pundit. Any help would be greatly appreciated -

i've been trying wrap head around concept of policy, seems straightforward enough--a policy set of rules access system privileges , resources determined.

simple enough.

so, in order user within system access list of, say, every other user within system, they'd require necessary credentials (e.g., maybe being administrator or being logged in registered user). i'm struggling understand @ basic level how use pundit accomplish this. case documentation lots of open-source software i've attempted learn, pundit documentation seems @ best allude how tool should work not provide full , concrete example of basic use case. i'm looking here "hello world" example don't spend 3 or 4 days piecing confused , half-working implementation myself small this. furthermore, examples pundit provide serve confuse matters worse.

i've created test application attempts use devise (which seem understand , able use enough) , pundit in combination. far:

• a user can register site.
• a user can log in , log out.

now, i'd do--which basic , shouldn't have furrowing brow soon--is restrict user's access users index page based on whether logged system, , it's here i'm stuck.

what have tried far?

• i've installed pundit per documentation.
• i've included pundit in application_controller.rb

• i've generated user policy, looks this:

  class userpolicy < applicationpolicy   class scope < scope     puts "inside userpolicy scope."     attr_reader :user      def initialize(user)       @user = user     end      def index       puts "you've hit index."     end      def resolve       scope     end   end end   class userscontroller < applicationcontroller   before_filter :authenticate_user!   after_action :verify_authorized   def index     @users = user.all     authorize current_user   end end 

at point, i'm lost how associate two--the userpolicy class , userscontroller.

i seem @ least able print console message "inside userpolicy scope." otherwise see following error message in browser:

"not allowed index? #"

what missing and, if nothing else, gap in own knowledge that's making , other rails-related tools difficult learn? i'm professional software engineer (historically, i've been front-end engineer , have within last couple of years been working become full-stack engineer), find myself getting stuck far open-source tools one.

pundit plain ruby objects set in rails structure.

i think confusion trying authorize user, think of more resource perspective. limiting users access object via restful action. scopes limit can see, instance, admin scope.all, single user not allowed or able scope on users controller.

in application policy define helpers group types of users. here example.

class ticketpolicy < applicationpolicy   class scope < struct.new(:user, :scope)      def resolve        #allows government see organization        # allows citizens see nothing        if user.government?          scope.where(:organization_id => user.organization_id)        else          scope.where(:id => 0)        end      end   end     def index?     is_government   end    def show?     is_government && is_inside_organization(@record)   end    def create?     is_government && is_inside_organization(@record)   end    def new?     is_government && is_inside_organization(@record)   end    def update?     is_government && is_inside_organization(@record)   end    def edit?     if user.employee?       return is_mine(@record) && is_inside_organization(@record)     end     is_government && is_inside_organization(@record)   end    def destroy?     false   end end 

this limits access groups/roles , in controller call

authorize @thing 

then pundit take care of access based on policy.