class FixtureSet

Fixtures are a way of organizing data that you want to test against; in short, sample data.

To learn more about fixtures, read the ActiveRecord::FixtureSet documentation.

YAML

Like other Active Record-backed models, ActiveStorage::Attachment and ActiveStorage::Blob records inherit from ActiveRecord::Base instances and therefore can be populated by fixtures.

Consider a hypothetical Article model class, its related fixture data, as well as fixture data for related ActiveStorage::Attachment and ActiveStorage::Blob records:

# app/models/article.rb
class Article < ApplicationRecord
  has_one_attached :thumbnail
end

# fixtures/active_storage/blobs.yml
first_thumbnail_blob: <%= ActiveStorage::FixtureSet.blob filename: "first.png" %>

# fixtures/active_storage/attachments.yml
first_thumbnail_attachment:
  name: thumbnail
  record: first (Article)
  blob: first_thumbnail_blob

When processed, Active Record will insert database records for each fixture entry and will ensure the Active Storage relationship is intact.