Specs:
- Using Ruby on Rails for the project
- Include at least one has_many relationship (x has_many y; e.g. User has_many Recipes)
- Include at least one belongs_to relationship (x belongs_to y; e.g. Post belongs_to User)
- Include at least two has_many through relationships (x has_many y through z; e.g. Recipe has_many Items through Ingredients)
- Include at least one many-to-many relationship (x has_many y through z, y has_many x through z; e.g. Recipe has_many Items through Ingredients, Item has_many Recipes through Ingredients)
- The "through" part of the has_many through includes at least one user submittable attribute, that is to say, some attribute other than its foreign keys that can be submitted by the app's user (attribute_name e.g. ingredients.quantity)
- Include reasonable validations for simple model objects (list of model objects with validations e.g. User, Recipe, Ingredient, Item)