Rails route error? uninitialized constant ActiveResource::Base

Question

I'm following the Getting Started with Rails guide but ran into an issue opening http://localhost:3000

Shell output:

[2010-03-23 19:19:14] ERROR NameError: uninitialized constant ActiveResource::Base

Error in the browser:

Internal Server Error
uninitialized constant ActiveResource::Base
WEBrick/1.3.1 (Ruby/1.8.7/2009-06-12) at localhost:3000 

I followed the directions exactly as they were specified in the guide:

1. Ran rails generate controller home index
2. I removed index.html
3. Added root :to => "home#index" to config/routes.rb

I checked app/views/home/index.html.erb and it is indeed there.

I then used rails server to launch the server. At first attempt the browser loads a blank page, but afterwards starts showing the browser error above.

Why is it that Rails can't locate the index.html.erb file? Or is the error something different?

-

Running Rails 3.0beta with Ruby 1.8.7

Answer 1

If you're using the Getting Started guide I recommend that you don't use Rails 3.0 beta, as, well, it's a beta release. It's best to use the stable-of-the-moment 2.3.5.

Answer 2

uninitialized constant ActiveResource::Base

It looks like there's a problem with your Ruby/Rails setup.

Do you have more than one version of Ruby on your system? It could be that the version of Ruby you're using to run your app is looking for the Rails gems (ActiveResource::Base) in the wrong repository.

Answer 3

I have this error as well. I am running Ruby 1.8.7 p249 under RVM - Rails 3 beta3 on Ubuntu (Lucid Lynx). The strange thing is I have the exact same setup (RVM, Ruby version & gems) on my Mac and it works fine.

UPDATE: I tried again using RVM to switch to Ruby-1.9.2-HEAD and everything is working as expected. Still doesn't solve problem but it get Rails 3 working at least.