Access attributes in ActiveRecord::Associations::CollectionProxy - ruby-on-rails

Question

I am trying to write a custom function that will throw an error if the amount of associated objects are >=4
I am wondering how i can access the keys/values in the contained hash and run a validation on it
if i do this
animal = FactoryGirl.create(:animal, images_count: 4)
a = animal.animal_images
ap(a)
I get this returned
#<ActiveRecord::Associations::CollectionProxy [
#<AnimalImage id: 520, animal_id: 158, image: "yp2.jpg", created_at: "2014-10-15 13:45:11", updated_at: "2014-10-15 13:45:11">,
#<AnimalImage id: 521, animal_id: 158, image: "yp2.jpg", created_at: "2014-10-15 13:45:11", updated_at: "2014-10-15 13:45:11">,
#<AnimalImage id: 522, animal_id: 158, image: "yp2.jpg", created_at: "2014-10-15 13:45:11", updated_at: "2014-10-15 13:45:11">,
#<AnimalImage id: 523, animal_id: 158, image: "yp2.jpg", created_at: "2014-10-15 13:45:11", updated_at: "2014-10-15 13:45:11">
]
So i thought of using .map
animal = FactoryGirl.create(:animal, images_count: 4)
a = animal.animal_images
map = a.each.map { |i| i.image }
if map.length >= 4
ap('MORE THAN 4 IMAGES')
end
"MORE THAN 4 IMAGES"
So that iterates through the CollectionProxy. However how can i get this formatted into a correct rspec test and perform the logic in a custom validation function.
I thought my test would look like this
it 'should display an error message when too many images are uploaded' do
animal = FactoryGirl.create(:animal, images_count: 4)
animal.max_num_of_images
expect(animal.errors[:base]).to include("Max of 3 images allowed")
end
and just to get the pass for now (add error message) with no logic i have
class AnimalImage < ActiveRecord::Base
belongs_to :animal
validate :max_num_of_images, :if => "image?"
def max_num_of_images
errors.add(:base, "Max of 3 images allowed")
end
end
but it seems as if the test doesnt get past the first line
ActiveRecord::RecordInvalid:
Validation failed: Max of 3 images allowed
the above is thrown in the console
This is my factory
FactoryGirl.define do
factory :animal, class: Animal do
ignore do
images_count 0
end
after(:create) do |animal, evaluator|
create_list(:animal_image, evaluator.images_count, animal: animal)
end
end
end
FactoryGirl.define do
factory :animal_image do
image { File.open("#{Rails.root}/spec/fixtures/yp2.jpg") }
end
end
i'm probably going about this in the most backwards way possible, does anyone have any suggestions please
thanks

Answer 1

I am trying to write a custom function that will throw an error if the amount of associated objects are >=4
You are overcomplicating things. If you just want to count the number of records in a collection then you can simply do animal.animal_images.size. So your model will look like this:
class Animal < ActiveRecord::Base
has_many :animal_images
validate :max_num_of_images
def max_num_of_images
errors.add(:base, "Max of 3 images allowed") if self.animal_images.size >= 4
end
end