How to check class in a policy's scope

Question

Project is with Rails + Pundit. Fruit class has two subclasses:

Tropical < Fruit
Temperate < Fruit

In fruit_policy.rb I got this:

class Scope < Scope
    def resolve
      if user.is_near_equator
        scope.where(class: Tropical)
      else
        scope.where(class: Temperate)
      end
    end
  end

The class check above gives me:

NameError (uninitialized constant Fruit::Tropical...
_________________________________________^^^^^^^^^

Is it possible to check the class within a scope in a policy? If so, how?

how about `scope.where(class: ::Tropical)`? – WALVISK Jul 23 '22 at 04:53 — WALVISK, Jul 23 '22 at 04:53
Gave this a shot and it results to the same error. – nakakapagpabagabag Jul 23 '22 at 07:50 — nakakapagpabagabag, Jul 23 '22 at 07:50

spickermann · Accepted Answer · 2022-07-23T08:43:47.993

2

When you implemented the subclasses with STI and followed Rails naming conventions for database columns then you can scope the query to a subclass by filtering on the type columns with the desired class name as a string:

def resolve
  if user.is_near_equator
    scope.where(type: 'Fruit::Tropical')
  else
    scope.where(type: 'Fruit::Temperate')
  end
end

edited Jul 23 '22 at 08:43

answered Jul 23 '22 at 06:02

spickermann

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Completely missed to think of this, had to do `type: 'Fruit::Tropical'` / `type: 'Fruit::Temperate'` to make it work correctly. – nakakapagpabagabag Jul 23 '22 at 07:51

How to check class in a policy's scope

1 Answers1