data-definition.rb

class User
  # created by session id to identify children
  field :sessionId, String
end

class Card
  field :frontMeaning, String
  field :frontPicture, Picture
  field :backMeaning, String
  field :backPicture, Picture
end

class Picture
  field :filename
  field :imagePath
end

class Test
  field :cards, Array[Card]
  field :createdAt, Date
  field :userId, String
  field :testType, String, options: ["frontToBack", "backToFront"]
end