Rails STI overriding scopes

Question

Let's say I have a STI setup as follows:

class User < ActiveRecord::Base
  scope :busy, -> { where('busy_factor > 1') }
end

class HeroUser < User
  scope :busy, -> { where('busy_factor > 5') }
end

So, hero users have a different threshold for the busy scope.

Now, if I do this, I get warnings:

Creating scope :busy. Overwriting existing method HeroUser.busy.

Everything seems to function correctly, but I'm wondering if there's a better way to do this.

Does `HeroUser` actually inherit from `User` rather than `ActiveRecord::Base` ? — Shadwell, Nov 09 '12 at 20:55

score 8 · Accepted Answer · answered Nov 09 '12 at 20:53

8

A cleaner way would be the following:

Remove scope for descendant models
Introduce a class method (i.e. busy_factor) which would return busy factor for that specific type of models.
Override this class methods in descendants where appropriate.
Rewite the scope in base class as:

scope :busy, -> { where('busy_factor > ?', self.busy_factor) }

Hope this helps.

answered Nov 09 '12 at 20:53

Anton

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Yes, why are you asking? – Anton Apr 04 '14 at 18:35

Rails STI overriding scopes

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