```ruby
FactoryGirl.define do
  factory :web_service, class: 'Service' do
    name "web"
    cpu 128
    memory 128
    public true
  end
end
```

Add an association to service factory
user
```ruby
FactoryGirl.define do
  factory :web_service, class: 'Service' do
    name "web"
    cpu 128
    memory 128
    public true
    association :heritage, factory: :heritage
  end
end
```
assistant