# Using ActiveResource to copy models with the same class?

**URL:** <https://www.ruby-forum.com/t/using-activeresource-to-copy-models-with-the-same-class/104810>\
**Category:** Rails\
**Created:** [May 22, 2007, 8:39pm UTC](https://www.ruby-forum.com/t/using-activeresource-to-copy-models-with-the-same-class/104810 "2007-05-22T20:39:18Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![stepheneb](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/71e660/32.png) [@stepheneb](https://www.ruby-forum.com/u/stepheneb)\
**Post date:** [May 22, 2007, 8:39pm UTC](https://www.ruby-forum.com/t/using-activeresource-to-copy-models-with-the-same-class/104810/1 "2007-05-22T20:39:18Z")

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I’d like to be able to copy model objects from one site instance of  
my rails application to another and I’m wondering if I can use or  
adapt ActiveRecord for this purpose.

The problem I have at the start is that the models have the same  
classname on both sites.

So while this works great in script/console running on  
[railsapp1.domain.com](http://railsapp1.domain.com):

class Activity \< ActiveResource::Base  
self.site = “[http://railsapp2.domain.com](http://railsapp2.domain.com)”  
end

activities = Activity.find(:all)

It’s not clear how I now get access to the local ActiveRecord class  
called Activity on the running rails instance [railsapp1.domain.com](http://railsapp1.domain.com).

Has anybody tried doing this?

---

<div class="post-metadata">

**Author:** ![stepheneb](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/71e660/32.png) [@stepheneb](https://www.ruby-forum.com/u/stepheneb)\
**Post date:** [May 22, 2007, 10:15pm UTC](https://www.ruby-forum.com/t/using-activeresource-to-copy-models-with-the-same-class/104810/2 "2007-05-22T22:15:29Z")

</div>

> I’d like to be able to copy model objects from one site instance of  
> my rails application to another and I’m wondering if I can use or  
> adapt ActiveRecord for this purpose.

I figured it out and I thought other people might like to know.

I’m using edge rails (rev 6786) checked out with Piston.

The following was all done in script/console.

First I put my ActiveResource classes in a Module so there wouldn’t be  
any name space clash with the identically named existing local  
ActiveRecord classes:

module Remote  
class RemoteDiy \< ActiveResource::Base  
self.site = “[http://railsapp2.domain.com/](http://railsapp2.domain.com/)”  
end  
class Level \< RemoteDiy; end  
class Subject \< RemoteDiy; end  
class Unit \< RemoteDiy; end  
end

Then I just got the complete collections of levels, subjects, and units  
using a syntax identical to ActiveRecord:

levels = Remote::Level.find(:all); puts “copied: #{levels.length}”  
subjects = Remote::Subject.find(:all); puts “copied:  
#{subjects.length}”  
units = Remote::Unit.find(:all); puts “copied: #{units.length}”

Finally I created local ActiveRecord objects with attributes of each  
remote object.

levels.each { |l| Level.create(l.attributes) unless  
Level.find\_by\_name(l.attributes[‘name’]) }; nil  
subjects.each { |s| Subject.create(s.attributes) unless  
Subject.find\_by\_name(s.attributes[‘name’]) }; nil  
units.each { |u| Unit.create(u.attributes) unless  
Unit.find\_by\_name(u.attributes[‘name’]) }; nil

Done! I like it!

I did this because I wanted to synch my development environment with  
copies of data from the production application.

## Now I need to learn more about how to use ActiveResource to create associations and their attributes. Any pointers to working code would be greatly appreciated.

- Stephen B.  
Concord Consortium, [http://www.concord.org](http://www.concord.org)