FactoryGirl specifying create_list count for deeply nested association - factory-bot

Question

The following is the association set-up:
Categories has many Chapters
Chapters has many Pages
Pages have one Text or Audio
I would like to generate records at the Category level and to specify the number of Chapters, Pages, and an optional Text or Audio record.
I am aware of using create_list to specify the first level of associations (Chapters). Is there any way to specify the count for the deeper associations? Initial thought tells me to nest the after(:create). Would that be the correct approach?
FactoryGirl.define do
factory :category do
ignore do
chapters_count 1
end
trait :with_chapters do
after(:create) do |instance, evaluator|
create_list :chapter, evaluator.chapters_count, category: instance
end
end
trait :with_chapters_and_pages do
...?
end
trait :with_chapters_and_pages_with_text do
...?
end
trait :with_chapters_and_pages_with_audio do
...?
end
end
end

Answer 1

After playing around with FactoryGirl and reading the syntax/methods.rb code, I came up with a working solution. If others have a better approach, please share :)
# category_factory.rb
FactoryGirl.define do
# Fields
# --------------------------------------------------
(...)
# Transient Attributes
# --------------------------------------------------
ignore do
chapter_count 1 # Number of associated Chapters to create
page_count 1 # Number of Chapter associated Pages to create
page_type :with_text # Page type either :with_text (default) or :with_audio
end
# Traits
# --------------------------------------------------
trait :with_chapter do
after(:create) do |instance, evaluator|
create_list :chapter, evaluator.chapter_count, category: instance
end
end
trait :with_chapter_and_page do
after(:create) do |instance, evaluator|
create_list :chapter, evaluator.chapter_count, :with_page, category: instance, page_count: evaluator.page_count, page_type: evaluator.page_type
end
end
end
# chapter_factory.rb
FactoryGirl.define do
# Fields
# --------------------------------------------------
(...)
category
# Transient Attributes
# --------------------------------------------------
ignore do
page_count 1 # Number of Chapter associated pages to create
page_type :with_text # Page type either :with_text (default) or :with_audio
end
# Traits
# --------------------------------------------------
trait :with_page do
after(:create) do |instance, evaluator|
create_list :page, evaluator.page_count, evaluator.page_type, chapter: instance
end
end
end
# page_factory.rb
FactoryGirl.define do
# Fields
# --------------------------------------------------
(...)
chapter
# Traits
# --------------------------------------------------
trait :with_text do
after(:create) do |instance, evaluator|
create :text, page: instance
end
end
trait :with_audio do
after(:create) do |instance, evaluator|
create :audio, page: instance
end
end
end
# text_factory.rb & audio_factory.rb
(...)
There is some repeat with the transient attributes. Not sure how to DRY it up...