Rails controller concerns for using pundit with scope of controller

scoped_policies.rb

# app/controllers/concerns/scoped_policies
# add `include ScopedPolicies` to your scoped base controller such as Api::BaseController
module ScopedPolicies
  extend ActiveSupport::Concern

  included do
    helper_method :authorize
    helper_method :policy_scope
  end

  # These are workarounds for the lack of support for namespacing in pundit
  # https://github.com/elabs/pundit/issues/12
  def controller_namespace
    @controller_namespace ||= self.class.to_s.sub(/::[A-z]*Controller/, '')
  end

  def authorize(record, query = nil)
    klass = "#{controller_namespace}::#{record.model_name}Policy".constantize
    policy = klass.new(current_user, record)
    query ||= "#{params[:action]}?"

    @_policy_authorized = true

    unless policy.public_send(query)
      error = Pundit::NotAuthorizedError.new("not allowed to #{query} this #{record}")
      error.query, error.record, error.policy = query, record, policy
      raise error
    end

    true
  end

  def policy_scope(scope)
    klass = "#{controller_namespace}::#{scope.model_name}Policy::Scope".constantize
    policy = klass.new(current_user, scope)

    @_policy_scoped = true

    policy.resolve
  end
end

I didn't even see that. Thank you for pointing it out.