Applying default conditions to a model's find, find_by_*

rubyonrails-talk
1

What is the best solution for applying a default condition to a model, for example only records where active is boolean true? My initial implementation overrode the find method using with_scope to apply the condition, but I soon discovered that didn't work with the will_paginate plugin.

I currently have a named_scope called :active that applies the conditions, but I'm not sure how to incorporate that so that it is always applied to find and find_by_* without having to use it inside of the controller.

I'd also like to apply a default sort order and have this code. Could I follow similar logic for applying the condition?

  def self.find(*args)     options = args.last.is_a?(Hash) ? args.pop : {}     if not options.include? :order       options[:order] = 'created_at desc'     end     args.push(options)     super   end

2

If you can move to Rails 2.3, which is currently in release candidate testing, you could use default scoping:

http://ryandaigle.com/articles/2008/11/18/what-s-new-in-edge-rails-default-scoping

Regards,

Craig

3

Not at this point, so I'd prefer to come up with a solution using 2.2.2.

4

At your model, override the find method:

class SomeModel < ActiveRecord::Base

  class << self

    def find(*args)       with_scope( :conditions => {:property => 'value'} ) do         super(*args)       end     end

  end

end

5

I originally used a with_scope, but that doesn't play nicely with will_paginate.