Under Rails 2.3.2 using a completely brand new project, I have 2
models:
class Author < ActiveRecord::Base
# name:string
end
class Book < ActiveRecord::Base
# title:string
belongs_to :author # author_id
end
And a simple test where i create a Book with an Author using the
belongs_to and then update the foreign key directly:
require ''test_helper''
class BookTest < ActiveSupport::TestCase
test "foreign key updating" do
a1 = Author.create! :name => ''author 1''
b = Book.create! :title => ''rails'', :author => a1
a2 = Author.create! :name => ''author 2''
b.update_attributes! :author_id => a2.id
assert_equal a2.id, b.author_id # author_id is still a1.id!
end
end
The test fails on the last line. Am i doing something wrong or is
this expected behaviour?
your Author should :have_many :books You also want to do something like this: dave = Author.create(:name => ''Dave Thomas'') pickaxe = dave.books.build(:title => ''Programming Ruby 1.9'') On Sun, May 24, 2009 at 3:46 AM, Sean K <sskirby-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:> > Under Rails 2.3.2 using a completely brand new project, I have 2 > models: > > class Author < ActiveRecord::Base > # name:string > end > > class Book < ActiveRecord::Base > # title:string > belongs_to :author # author_id > end > > And a simple test where i create a Book with an Author using the > belongs_to and then update the foreign key directly: > > require ''test_helper'' > > class BookTest < ActiveSupport::TestCase > test "foreign key updating" do > a1 = Author.create! :name => ''author 1'' > b = Book.create! :title => ''rails'', :author => a1 > a2 = Author.create! :name => ''author 2'' > b.update_attributes! :author_id => a2.id > assert_equal a2.id, b.author_id # author_id is still a1.id! > end > end > > The test fails on the last line. Am i doing something wrong or is > this expected behaviour? > > > >-- Jeff Schoolcraft http://thequeue.net/blog/ --~--~---------~--~----~------------~-------~--~----~ 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 rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
Jeff Schoolcraft is right. Your Author model should have this line :has_many :books In faat you should specify all the db relations in your model files, all of them. cheers
Thanks for the replies. However, changing the Author to: class Author < ActiveRecord::Base has_many :books end doesn''t change the outcome of the test. The problem that i''m having seems to be that the foreign key (Book.author_id) is not being updated by update_attributes. This smells like a bug to me. On May 24, 6:08 am, fRAnKEnSTEin <shirkav...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:> Jeff Schoolcraft is right. Your Author model should have this line > > :has_many :books > > In faat you should specify all the db relations in your model files, > all of them. > > cheers
You are correct, Jeff, setting the author using the create method on a
has_many works:
test "something" do
a1 = Author.create! :name => ''author 1''
b = a1.books.create! :title => ''rails''
a2 = Author.create! :name => ''author 2''
b.update_attributes! :author_id => a2.id
assert_equal a2.id, b.author_id
end
And so does setting the author via the foreign key:
test "something" do
a1 = Author.create! :name => ''author 1''
b = Book.create! :title => ''rails'', :author_id => a1
a2 = Author.create! :name => ''author 2''
b.update_attributes! :author_id => a2.id
assert_equal a2.id, b.author_id
end
So why doesn''t it like it when the belongs_to is used? Seems odd.
On May 24, 6:04 am, Jeff Schoolcraft
<jeffrey.schoolcr...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:> your Author should :have_many :books
> You also want to do something like this:
>
> dave = Author.create(:name => ''Dave Thomas'')
> pickaxe = dave.books.build(:title => ''Programming Ruby
1.9'')
>
>
>
> On Sun, May 24, 2009 at 3:46 AM, Sean K
<sski...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>
> > Under Rails 2.3.2 using a completely brand new project, I have 2
> > models:
>
> > class Author < ActiveRecord::Base
> > # name:string
> > end
>
> > class Book < ActiveRecord::Base
> > # title:string
> > belongs_to :author # author_id
> > end
>
> > And a simple test where i create a Book with an Author using the
> > belongs_to and then update the foreign key directly:
>
> > require ''test_helper''
>
> > class BookTest < ActiveSupport::TestCase
> > test "foreign key updating" do
> > a1 = Author.create! :name => ''author 1''
> > b = Book.create! :title => ''rails'', :author
=> a1
> > a2 = Author.create! :name => ''author 2''
> > b.update_attributes! :author_id => a2.id
> > assert_equal a2.id, b.author_id # author_id is still a1.id!
> > end
> > end
>
> > The test fails on the last line. Am i doing something wrong or is
> > this expected behaviour?
>
> --
> Jeff Schoolcrafthttp://thequeue.net/blog/
before the update_attributes line, try adding b = Book.find(:first, "title => ''rails''") then b.update_attributes! :author_id => a2.id It seems that update_attributes will work from found object, not newly created object, and this is normally done under update action of controller Sean K wrote:> Under Rails 2.3.2 using a completely brand new project, I have 2 > models: > > class Author < ActiveRecord::Base > # name:string > end > > class Book < ActiveRecord::Base > # title:string > belongs_to :author # author_id > end > > And a simple test where i create a Book with an Author using the > belongs_to and then update the foreign key directly: > > require ''test_helper'' > > class BookTest < ActiveSupport::TestCase > test "foreign key updating" do > a1 = Author.create! :name => ''author 1'' > b = Book.create! :title => ''rails'', :author => a1 > a2 = Author.create! :name => ''author 2'' > b.update_attributes! :author_id => a2.id > assert_equal a2.id, b.author_id # author_id is still a1.id! > end > end > > The test fails on the last line. Am i doing something wrong or is > this expected behaviour?
> Sean K wrote: >> Under Rails 2.3.2 using a completely brand new project, I have 2 >> models: >> >> class Author < ActiveRecord::Base >> # name:string >> end >> >> class Book < ActiveRecord::Base >> # title:string >> belongs_to :author # author_id >> end >> >> And a simple test where i create a Book with an Author using the >> belongs_to and then update the foreign key directly: >> >> require ''test_helper'' >> >> class BookTest < ActiveSupport::TestCase >> test "foreign key updating" do >> a1 = Author.create! :name => ''author 1'' >> b = Book.create! :title => ''rails'', :author => a1 >> a2 = Author.create! :name => ''author 2'' >> b.update_attributes! :author_id => a2.id >> assert_equal a2.id, b.author_id # author_id is still a1.id! >> end >> end >> >> The test fails on the last line. Am i doing something wrong or is >> this expected behaviour? >Actually when you update the attribute for the one object, the ram- cached copy isn''t updated for the other (association), so you need to reload it. b.reload you''re probably better off saying: b.author = a2 I think. ---------------------------------------------- Blog: http://random8.zenunit.com/ Twitter: http://twitter.com/random8r Learn: http://sensei.zenunit.com/ Latest: How to use Unix basics at http://sensei.zenunit.com/> >
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