```ruby
module AwesomeAccess::ActionControllerConcern

  extend ActiveSupport::Concern

  included do
  end

  private

    def awesome_access_restrict
      redirect_to AwesomeAccess.configuration.redirect_restricted unless awesome_access_person
    end

    def awesome_access_authenticate(email, password)
        if person = Person.where(email: email).where(active: true).first.try(:authenticate, password)
          session[:awesome_access] = {}
          session[:awesome_access][:person_id] = person.id
          if person.password_token
            person.password_token = ''
            person.save
          end
          person.last_seen = DateTime.now
          person.save
          return true
        end
        false
    end

    def awesome_access_person
      return @awesome_access_person ||= Person.find(session[:awesome_access][:person_id]) if session[:awesome_access]
    end

    def awesome_access_person=(person)
      if session[:awesome_access]
        return session[:awesome_access][:person_id] = person.id
      end
      false
    end

    def awesome_access_destroy
      if session[:awesome_access]
        session[:awesome_access] = nil
        return true
      end
      false
    end
end
```

Fix login error when password_digest is nil.
user
```ruby
module AwesomeAccess::ActionControllerConcern

  extend ActiveSupport::Concern

  included do
  end

  private

    def awesome_access_restrict
      redirect_to AwesomeAccess.configuration.redirect_restricted unless awesome_access_person
    end

    def awesome_access_authenticate(email, password)
      if person = Person.where(email: email).where(active: true).first
        if person.password_digest != nil
          if person.authenticate password
            session[:awesome_access] = {}
            session[:awesome_access][:person_id] = person.id
            if person.password_token
              person.password_token = ''
            end
            person.last_seen = DateTime.now
            person.save
            return true
          end
        end
      end
      false
    end

    def awesome_access_person
      return @awesome_access_person ||= Person.find(session[:awesome_access][:person_id]) if session[:awesome_access]
    end

    def awesome_access_person=(person)
      if session[:awesome_access]
        return session[:awesome_access][:person_id] = person.id
      end
      false
    end

    def awesome_access_destroy
      if session[:awesome_access]
        session[:awesome_access] = nil
        return true
      end
      false
    end
end
```
assistant