I need to store people, albums, photos, and the order that photos
appear in an album, so I decided to try adding a "position" attribute
to the association between Photo and Album. Consider the following
models:
class Person
include DataMapper::Resource
...
end
class Album
include DataMapper::Resource
...
has n, :photos, "Photo", :through => :album_photos, :via => :photo
end
class Photo
include DataMapper::Resource
...
belongs_to :person, :required => true
has n, :albums, "Album", :through => :album_photos, :via => :album
end
class AlbumPhoto
include DataMapper::Resource
property :position, Integer, :default => 1
belongs_to :album, :key => true
belongs_to :photo, :key => true
end
First, is such the right way to achieve this sort of thing? I didn't
see anything like this in the documentation.
To add a wrinkle, I have a model called Book which has a 1:M
relationship with Album. When I execute the following code
album.album_photos.destroy
album.album_photos << AlbumPhoto.new({:position =>3})
book.update
I get "DataMapper::UpdateConflictError: Book#update cannot be called
on a dirty resource"
I am curious if my models are defined correctly. If so, how can I
delete all prior associations and update their positions "cleanly"?
Thanks.
--
You received this message because you are subscribed to the Google Groups
"DataMapper" 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/datamapper?hl=en.
