Serialize permissions (e.g. CanCan) with active_model_serializers
active-model-serializers, activemodel, cancan, ruby-on-rails
Solution
First, to get access to the `current_user` in the serializer context, use the new scope feature:
class ApplicationController < ActionController::Base
...
serialization_scope :current_user
end
In case you are instantiating serializers manually, be sure to pass the scope:
model.active_model_serializer.new(model, scope: serialization_scope)
Then inside the serializer, add custom methods to add your own authorization pseudo-attributes, using `scope` (the current user) to determine permissions.
If you are using CanCan, you can instantiate your Ability class to access the `can?` method:
attributes :can_update, :can_delete
def can_update
# `scope` is current_user
Ability.new(scope).can?(:update, object)
end
def can_delete
Ability.new(scope).can?(:delete, object)
end
Problem
How do I serialize permissions with active_model_serializers? I don't have access to `current_user` or the `can?` method in models and serializers.