Rails tip if you use association proxy methods

20th May 2008

Rails tip if you use association proxy methods

I like doing following in my code:

class Blah < ActiveRecord::Base
  has_many :somethings
end

class Something < ActiveRecord::Base
  def self.for(person)
    find(:first, :conditions => {:owner_name => person})
  end
end 

# And then later
@the_blah.somethings.for("dima") # => #<Something ....>

But I also can accidentally do this and break the expectation for the code, since I don’t have full conditions specified in the Something.for method:

Something.for("dima")

Right, no conditions from Blah will be applied and first Something with name “dima” will be returned. However, here’s a workaround I figured out, just write a Something.for method like this:

class Something < ActiveRecord::Base
  def self.for(person)
    raise unless scoped?(:find)
    find(:first, :conditions => {:owner_name => person})
  end
end

Dima Sabanin

20th May 2008

Rails tip if you use association proxy methods

sdmitry at gmail.com