#1043 confirmed

DataMapper::Resource is not calling initialize definined in models.

Reported by Postmodern | September 16th, 2009 @ 04:43 PM

I just noticed that DataMapper 0.10.0 is not calling the "initialize" method defined in the models. I'm not sure when this behavior regressed.

require 'dm-core'

class User

  include DataMapper::Resource

  property :id, Serial

  property :name, String

  attr_reader :var

  def initialize(attributes={},&block)

    @var = 2


DataMapper.setup(:default, 'sqlite3::memory:')

User.create(:name => 'joe')

puts User.first.inspect
puts User.first.var

As you can see from the example, resources returned by "first" do not have the instance variable @var set.

Comments and changes to this ticket

  • Postmodern

    Postmodern September 16th, 2009 @ 05:03 PM

    • Assigned user set to “Dan Kubb (dkubb)”
  • Dan Kubb (dkubb)

    Dan Kubb (dkubb) September 16th, 2009 @ 05:26 PM

    • State changed from “new” to “confirmed”
    • Tag changed from 0.10.0, dm-core, first, initialization, regression, resource to 0.10.0, dm-core, first, initialization, resource

    The initialize method is only called when originally creating the object, not when it is being loaded from the datastore.

    While it could be argued that this behavior is wrong, I know it was originally chosen for performance reasons.

    I'll think about this, and figure out if we can use the initialize method when loading or not.

    The only problem I can think of is when you have a totally custom initialize method that takes something different from a single Hash.. if we call it on load, DM isn't going to know what arguments to pass in.

  • Postmodern

    Postmodern September 16th, 2009 @ 06:58 PM

    As an easy work around, you can create a custom Model module for your models to override Class#allocate.

    module Project
      module Model
        def self.included(base)
          base.module_eval do
            def self.allocate
              resource = super
              return resource
  • Postmodern

    Postmodern September 16th, 2009 @ 06:58 PM



  • Dan Kubb (dkubb)

Please Sign in or create a free account to add a new ticket.

With your very own profile, you can contribute to projects, track your activity, watch tickets, receive and update tickets through your email and much more.

New-ticket Create new ticket

Create your profile

Help contribute to this project by taking a few moments to create your personal profile. Create your profile »

People watching this ticket