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Question

I'm somewhat of a Rails beginner, and can't shake the feeling that I'm overlooking something stupid, but here goes. I'm building a simple online game that allows one user to "challenge" another, and I have the following models:

class User < ActiveRecord:Base
  has_one :challenge
end

class Challenge < ActiveRecord:Base
  belongs_to :user
  belongs_to :target, :class_name => 'User'
end

The database fields are what you'd expect: Challenge has a user_id and target_id , User has a username and some password-related fields.

From an empty database, I create two Users (which receive IDs 1 and 2) and a single Challenge with user_id 1 and target_id 2 . From the console, Challenge.find(1).target returns user 2, as expected. What's not expected is that User.find(1).challenge.target returns not user 2, but the Challenge itself!

Needless to say, I'm lost here. It seems like something this basic should Just Work(tm). Any ideas?

Answer 1

You're doing things wrong here. User has one challenge should be like :

class User < ActiveRecord:Base
  has_one :challenge
end

class Challenge < ActiveRecord:Base
  belongs_to :user
end

Now, a challenge simply has a user_id and you can now use something like :

user.challenge

to get that challenge. Then, you just have a challenger_id for the person that makes the challenge.

If you want to get a challenge based on the challenger_id, you just create a finder or scope like :

Challenge.find_by_challenger_id(..)

EDIT - SOLUTION IN MY COMMENT BELOW :

Hmm, i think that target is an association method. Try changing to something like challenger and i think it will work.