Rails - Aug 2009 - Migration erros when truning on config.threadsafe!

When turning on config.threadsafe! in production environment and
trying to migrate production database I get odd errors like
uninitialized constant AddAdminToUsers::User, here is the migration
file data:


class AddAdminToUsers < ActiveRecord::Migration
  def self.up
    User.create!(:username=>
''admin'',:first_name=>"admin",:last_name=>"admin",
:password=>
''admin@exam$'',:password_confirmation=>
''admin@exam$'')
  end

  def self.down
  end
end

This error never shows up when that setting is off...

Ok just for the record, i found a similar thread regarding that here
https://rails.lighthouseapp.com/projects/8994/tickets/2506-models-are-not-loaded-in-migrations-when-configthreadsafe-is-set
, and all I did to fix it is to require the user model at the top of
this migration file:

require ''user''


On Aug 25, 3:46 am, khelll
<khel...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:
> When turning on config.threadsafe! in production environment and
> trying to migrate production database I get odd errors like
> uninitialized constant AddAdminToUsers::User, here is the migration
> file data:
>
> class AddAdminToUsers < ActiveRecord::Migration
>   def self.up
>     User.create!(:username=>
>
''admin'',:first_name=>"admin",:last_name=>"admin",
 :password=>
> ''admin@exam$'',:password_confirmation=>
''admin@exam$'')
>   end
>
>   def self.down
>   end
> end
>
> This error never shows up when that setting is off...

I''ll just throw out the notion that this may not be the right solution.

In general, if you actually *use* a model to do something in a  
migration, you should define a minimal version of the model *inside*  
the migration class. For example:

class AddAdminToUsers < ActiveRecord::Migration
   class User < ActiveRecord::Base; end
   def self.up
     User.create!(:username=>''admin'',
          :first_name=>"admin", :last_name=>"admin",
          :password=>''admin@exam$'',
          :password_confirmation=>''admin@exam$'')
   end

   def self.down
   end
end

That way changes to the model or the database don''t lead to odd  
failures later on -- like when a production deployment is several  
migration versions behind and tries to do some now incompatible things  
with an earlier migration. Think what would happen if the
''username''
column were to be renamed to ''login'' in a later migration and
both
needed to be applied.

-Rob

Rob Biedenharn		http://agileconsultingllc.com
Rob-xa9cJyRlE0mWcWVYNo9pwxS2lgjeYSpx@public.gmane.org

On Aug 25, 2009, at 1:09 PM, khelll wrote:
>
> Ok just for the record, i found a similar thread regarding that here
>
https://rails.lighthouseapp.com/projects/8994/tickets/2506-models-are-not-loaded-in-migrations-when-configthreadsafe-is-set
> , and all I did to fix it is to require the user model at the top of
> this migration file:
>
> require ''user''
>
>
> On Aug 25, 3:46 am, khelll
<khel...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>> When turning on config.threadsafe! in production environment and
>> trying to migrate production database I get odd errors like
>> uninitialized constant AddAdminToUsers::User, here is the migration
>> file data:
>>
>> class AddAdminToUsers < ActiveRecord::Migration
>>   def self.up
>>     User.create!(:username=>
>>
''admin'',:first_name=>"admin",:last_name=>"admin",
:password=>
>> ''admin@exam$'',:password_confirmation=>
''admin@exam$'')
>>   end
>>
>>   def self.down
>>   end
>> end
>>
>> This error never shows up when that setting is off...