Modeling A Book With With Ruby on Rails Active Record

Question

Im modeling an online book with ruby on rails. The book has chapters, each chapter has pages. Modeling this part is easy. What id like to do is keep track of what pages each user has read and when and whether they liked that page / whether the user completed the book. How would one recommend modeling keeping track of this in rails? Id ideally like to say give me all the books the user is or has read, and then have access to the book plus state info for that user's reading of the book.

Answer 1

The BookState becomes the intermediate object between the user and the book.

class User < ActiveRecord::Base
   has_many :book_states
   has_many :books, :through => :book_state
end

class BookState < ActiveRecord::Base
   belongs_to :user
   belongs_to :book
end

class Book < ActiveRecord::Base
   has_many :book_states
end

BookState has the current location, the likes/dislikes, etc. If you ask for a user's bookStates, that will give you the books as well.

Answer 2

This makes a lot of sense. The one problem i see is collecting stats on a question (what percent of the time was this answered)? Since that data is in serialized hashes? What about this:

book
    has_many user_books
 has_many users through user_books
 has_many chapters

chapter
 belongs_to book
 has_many pages

page
 belongs_to chapter
 has_many user_pages

user
    has_many user_books
 has_many books through user_books

user_book
 belongs_to user
 belongs_to book
 has_many user_pages

user_page
 belongs_to user_book
 belongs_to page

What do you think?