Question

I am a beginner in Rails and i have a problem with scope.

I have my class with 2 scopes :

class Event < ActiveRecord::Base
  belongs_to :continent
  belongs_to :event_type 

   scope :continent, lambda { |continent|
     return if continent.blank?
     composed_scope = self.scoped
     composed_scope = composed_scope.where('continent_id IN ( ? )', continent).all
     return composed_scope
   }

   scope :event_type, lambda { |eventType|
     return if eventType.blank?
     composed_scope = self.scoped
     composed_scope = composed_scope.where('event_type_id IN ( ? )', eventType).all
     return composed_scope
   }

end

And in my controller i want to use this 2 scopes at the same time. I did :

def filter
  @event = Event.scoped
  @event = @event.continent(params[:continents]) unless params[:continents].blank?
  @event = @event.event_type(params[:event_type]) unless params[:event_type].blank?

  respond_with(@event)
end

But i doesn’t work, I have this error :

 undefined method `event_type' for #<Array:0x7f11248cca80>

It’s because the first scope return an array.

How can I do to make it work?

Thank you !

Answer 1

You should not append ‘.all’ in your scopes:

It transforms a chainable ActiveRelation into an Array, by triggering the SQL query.

So simply remove it.

Bonus:

Some refactoring:

scope :continent, lambda { |continent|   
  self.scoped.where('continent_id IN ( ? )', continent) unless continent.blank?
}