Active Record forgets methods! bug?

Rails
1

I have created a rails app.
When in development mode, I hit a problem the second time I try to
display a page from a particular controller: it raises a method_missing
exception because suddenly the model I am trying to use has forgotten
about all the methods I added to it, and all its association methods
(from has_one and has_many). Inspecting the model shows that it still
has it’s @attributes array.

In production mode, it works fine. Same result on Rails 1.x and 2.0.2.
Below is an example exception. In my DB, System has_many
test_results.

Any ideas?
Thanks,
-Sam.

undefined method `test_results’ for #System:0x2521eb0
RAILS_ROOT:
/Users/sam/Development/ideas/trunk/spierson/pbits/server/pbits2

Application Trace | Framework Trace | Full Trace
/Library/Ruby/Gems/1.8/gems/activerecord-2.0.2/lib/active_record/attribute_methods.rb:205:in
method_missing' app/controllers/results_controller.rb:34:inreport’
/Library/Ruby/Gems/1.8/gems/activerecord-2.0.2/lib/active_record/associations/association_proxy.rb:125:in
each' /Library/Ruby/Gems/1.8/gems/activerecord-2.0.2/lib/active_record/associations/association_proxy.rb:125:insend’
/Library/Ruby/Gems/1.8/gems/activerecord-2.0.2/lib/active_record/associations/association_proxy.rb:125:in
method_missing' /Library/Ruby/Gems/1.8/gems/activerecord-2.0.2/lib/active_record/associations/has_many_through_association.rb:133:inmethod_missing_without_paginate’
vendor/plugins/will_paginate/lib/will_paginate/finder.rb:93:in
method_missing' app/controllers/results_controller.rb:32:inreport’
/Library/Ruby/Gems/1.8/gems/actionpack-2.0.2/lib/action_controller/base.rb:1158:in
`send’
<snip - boring part deleted>

2

This is because of the file loading problem in development mode.
So for this, add the following statement on top of the ‘system.rb’ file.

requrie ‘test_result.rb’

Use the file names that you are using. I have given the file names in
assumption.

I hope it will work. Because I have experienced the same problem.

  • Karthik.
3

Sorry Karthink -> Karthik

4

Many thanks for your suggestion Karthink.
That was a good idea: require ‘test_result’ was indeed missing from
system.rb

Unfortunately this did not solve the problem.
Something more sinister is going on.

-Sam.

5

I dont know what else the problem is.

Did you restart the server after adding the statement? If not, please
try that also.

6

Karthi kn wrote:

Did you restart the server after adding the statement? If not, please
try that also.

Yes. Twice :slight_smile:

7

Can you show that controller code here?

8

Karthi kn wrote:

Can you show that controller code here?

No need - you cracked it!
I went further and put in appropriate require statements for EVERY
association in EVERY model.
That fixed it. I have some 2-step joins (using :through) and I think
one of those maybe was causing the problem.

Many thanks for your help!

-Sam.