# Uninitialized constant CachedModel

**URL:** <https://www.ruby-forum.com/t/uninitialized-constant-cachedmodel/162531>\
**Category:** Rails\
**Created:** [March 11, 2009, 12:33am UTC](https://www.ruby-forum.com/t/uninitialized-constant-cachedmodel/162531 "2009-03-11T00:33:32Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![vlo](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/9d8465/32.png) [@vlo](https://www.ruby-forum.com/u/vlo)\
**Post date:** [March 11, 2009, 12:33am UTC](https://www.ruby-forum.com/t/uninitialized-constant-cachedmodel/162531/1 "2009-03-11T00:33:32Z")

</div>

I just upgraded my app from 1.2.6 to 2.2.2. When I do the rake  
db:migrate, I hit “uninitialized constant CachedModel.” (Full stack at  
the end of the message.) I found out from doing a Google search that  
CachedModel and the initialization process created a chicken-and-egg  
problem long time ago. However, I thought that the problem was solved  
as I didn’t have to anything special to make it work in 1.2.6.

BTW, if I move the require ‘cached\_model’ before  
Rails::Initializer.run do |config|, it dies somewhere else. And I am  
pretty sure that it is not the recommended place for the require  
anyway.

Has anyone encountered this problem before? And how did you solve it?

Thanks,  
Vincent

P.S. Full stack:

uninitialized constant CachedModel  
/usr/lib64/ruby/gems/1.8/gems/activesupport-2.2.2/lib/active\_support/  
dependencies.rb:445:in `load_missing_constant' /usr/lib64/ruby/gems/1.8/gems/activesupport-2.2.2/lib/active_support/ dependencies.rb:77:in`const\_missing’  
/usr/lib64/ruby/gems/1.8/gems/activesupport-2.2.2/lib/active\_support/  
dependencies.rb:89:in `const_missing' /usr/local/myapp/app/models/baby.rb:1 (<= class Baby < CachedModel ) /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in`gem\_original\_require’  
/usr/lib/ruby/site\_ruby/1.8/rubygems/custom\_require.rb:31:in `require' /usr/lib64/ruby/gems/1.8/gems/activesupport-2.2.2/lib/active_support/ dependencies.rb:155:in`require’  
/usr/lib64/ruby/gems/1.8/gems/activesupport-2.2.2/lib/active\_support/  
dependencies.rb:262:in `require_or_load' /usr/lib64/ruby/gems/1.8/gems/activesupport-2.2.2/lib/active_support/ dependencies.rb:221:in`depend\_on’  
/usr/lib64/ruby/gems/1.8/gems/activesupport-2.2.2/lib/active\_support/  
dependencies.rb:133:in `require_dependency' /usr/lib64/ruby/gems/1.8/gems/rails-2.2.2/lib/initializer.rb:368:in`load\_application\_classes’  
/usr/lib64/ruby/gems/1.8/gems/rails-2.2.2/lib/initializer.rb:367:in  
`each' /usr/lib64/ruby/gems/1.8/gems/rails-2.2.2/lib/initializer.rb:367:in`load\_application\_classes’  
/usr/lib64/ruby/gems/1.8/gems/rails-2.2.2/lib/initializer.rb:365:in  
`each' /usr/lib64/ruby/gems/1.8/gems/rails-2.2.2/lib/initializer.rb:365:in`load\_application\_classes’  
/usr/lib64/ruby/gems/1.8/gems/rails-2.2.2/lib/initializer.rb:185:in  
`process' /usr/lib64/ruby/gems/1.8/gems/rails-2.2.2/lib/initializer.rb:112:in`send’  
/usr/lib64/ruby/gems/1.8/gems/rails-2.2.2/lib/initializer.rb:112:in  
`run' /usr/local/myapp/config/environment.rb:13 (<= Rails::Initializer.run do |config|) /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in`gem\_original\_require’  
/usr/lib/ruby/site\_ruby/1.8/rubygems/custom\_require.rb:31:in `require' /usr/lib64/ruby/gems/1.8/gems/activesupport-2.2.2/lib/active_support/ dependencies.rb:153:in`require’  
/usr/lib64/ruby/gems/1.8/gems/activesupport-2.2.2/lib/active\_support/  
dependencies.rb:521:in `new_constants_in' /usr/lib64/ruby/gems/1.8/gems/activesupport-2.2.2/lib/active_support/ dependencies.rb:153:in`require’  
/usr/lib64/ruby/gems/1.8/gems/rails-2.2.2/lib/tasks/misc.rake:3  
/usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:617:in `call' /usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:617:in`execute’  
/usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:612:in `each' /usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:612:in`execute’  
/usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:578:in  
`invoke_with_call_chain' /usr/lib/ruby/1.8/monitor.rb:242:in`synchronize’  
/usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:571:in  
`invoke_with_call_chain' /usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:588:in`invoke\_prerequisites’  
/usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:585:in `each' /usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:585:in`invoke\_prerequisites’  
/usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:577:in  
`invoke_with_call_chain' /usr/lib/ruby/1.8/monitor.rb:242:in`synchronize’  
/usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:571:in  
`invoke_with_call_chain' /usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:564:in`invoke’  
/usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:2027:in  
`invoke_task' /usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:2005:in`top\_level’  
/usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:2005:in `each' /usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:2005:in`top\_level’  
/usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:2044:in  
`standard_exception_handling' /usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:1999:in`top\_level’  
/usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:1977:in `run' /usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:2044:in`standard\_exception\_handling’  
/usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/lib/rake.rb:1974:in `run' /usr/lib64/ruby/gems/1.8/gems/rake-0.8.4/bin/rake:31 /usr/bin/rake:19:in`load’  
/usr/bin/rake:19

---

<div class="post-metadata">

**Author:** ![vlo](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/9d8465/32.png) [@vlo](https://www.ruby-forum.com/u/vlo)\
**Post date:** [March 11, 2009, 1:14am UTC](https://www.ruby-forum.com/t/uninitialized-constant-cachedmodel/162531/2 "2009-03-11T01:14:27Z")

</div>

Well, well, well. Problem solved. I should have reread the release  
notes. The easy solution is to use config.gems in environment.rb.

Vincent