On 8 August 2011 21:44, Stan McFarland <[email protected]> wrote: > Hi, > > Newbie here. I'm having to enter this from memory since my work is on > a closed network, so forgive any syntax errors. > > I'm trying to recreate some basic Google Plus functionality with > regards to users, posts, and circles - that is, a user can see a post > only if he/she is in one or more of the same circles that the post > belongs to: > > class User > has_and_belongs_to :circles > has_many :posts > class Post > has_and_belongs_to :circles > belongs_to :user # the user that created the post > class Circle > has_and_belongs_to :posts > has_and_belongs_to :users
Firstly each of those should be has_and_belongs_to_many, but I expect you knew that. Secondly, I don't know whether you realise, but I don't think the above will fully model the google+ concept. I think you need to model the asymmetric way that circles relate to users. I think you will need two relationships, firstly user has_many circles and circle belongs to user. This will map the fact that a user has a number of circles. Then you need to record who is *in* that circle via a has_and_belongs_to_many relationships, where you will need to use the :class_name specifier. Something like user has_and_belongs_to_many :member_of_circles, :class_name=>'Circle' Then the circles owned by a user are @user.circles and the circles that the user is in are @user.member_of_circles You will also need the equivalent reverse relationship to get all the users that are members of a circle. I have not tested that, in fact I am not sure I have used :class_name with a has_and_belongs_to relationship, I tend to prefer explicit join tables. If you are a beginner at Rails I think you might be better to start with something simpler, this is a non-trivial problem for the beginner. Have you worked through some good tutorials? I recommend railstutorial.org which is free to use online. Make sure you are using Rails 3 and that the tutorial is for Rails 3. Also work through the Rails Guides. Colin -- 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.
