On Tue, Oct 21, 2008 at 2:33 AM, Mark Reginald James <[EMAIL PROTECTED]>wrote:
> > Md. Kazim Zaidi wrote: > > Hello everyone, > > This is my first post to this list, so kindly remind me if I do > > something wrong. :-P > > > > When parent objects are saved, all the new children are saved. > > However, when the child objects validate themselves, they fail because > > the foreign key is nil. > > Domain logic in my application requires complex validations, which > > will just fail because the associated object is nil. I'm trying to > > illustrate using an over-simplified example: > > > > (also pasted at http://pastie.org/295133) > > *** Schema *** > > User(id, name, age) > > Book(id, title, author_id) > > > > *** app/models/user.rb *** > > class User < ActiveRecord::Base > > has_many :books, :foreign_key => 'author_id' > > end > > > > *** app/models/book.rb *** > > class Book < ActiveRecord::Base > > belongs_to :author, :class_name => 'User', :foreign_key => > > 'author_id' > > > > validates_presence_of :author_id > > end > > > > *** ./script/console *** > > u = User.new(:name => 'Shakespeare', :age => 444) > > u.books.build(:title => 'The Comedy of Errors') > > u.save! > > ActiveRecord::RecordInvalid: Validation failed: Books is invalid > > > > Bad Solution: Remove validates_presence_of :author_id from Book model. > > This makes the model unsafe, but things work. > > > > I hope I'm not following the best practices and somebody enlightens > > me. But if this is meant to be in this way, then how do I implement my > > validations on a Book? > > Use validates_presence_of :author instead. > > Currently you also have to do the build like > u.books.build(:title => 'The Comedy of Errors', :author => u) Thanks a lot! That does work. Currently? Is it about to be changed in 2.2? The API doesn't document this explicitly, and the fact that I need to pass author as parameter too isn't very obvious, IMHO. Thanks again. :-) -- - Kazim Zaidi Blog: http://tuxplayground.blogspot.com --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
