# Conflict with Mail Queue and Engines?

**URL:** <https://www.ruby-forum.com/t/conflict-with-mail-queue-and-engines/79304>\
**Category:** Engines\
**Created:** [December 14, 2006, 2:08am UTC](https://www.ruby-forum.com/t/conflict-with-mail-queue-and-engines/79304 "2006-12-14T02:08:07Z")\
**Posts on this page:** 7\
**Page:** 1

<div class="post-metadata">

**Author:** ![subimage](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/aca169/32.png) [@subimage](https://www.ruby-forum.com/u/subimage)\
**Post date:** [December 14, 2006, 2:08am UTC](https://www.ruby-forum.com/t/conflict-with-mail-queue-and-engines/79304/1 "2006-12-14T02:08:07Z")

</div>

I’m trying to use the Mail Queue plugin from:  
ruby script/plugin install svn://rubyforge.org/var/svn/mail-queue

When I try to deliver an email I’m getting the following stack trace.  
Looks like it’s conflicting with engines, but I can’t be sure. Anyone  
else seen this or know what might be going on?

* * *

You have a nil object when you didn’t expect it!  
You might have expected an instance of Array.  
The error occurred while evaluating nil.empty?

/Work/myapp/site/trunk/config/…/vendor/rails/activerecord/lib/…/…/activesupport/lib/active\_support/dependencies.rb:371:in  
`new_constants_in' /Work/myapp/site/trunk/config/../vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:199:in`load\_file’  
/Work/myapp/site/trunk/config/…/vendor/rails/activerecord/lib/…/…/activesupport/lib/active\_support/dependencies.rb:95:in  
`rails_pre_engines_require_or_load' /Work/myapp/site/trunk/config/../vendor/plugins/engines/lib/engines/dependencies_extensions.rb:60:in`rails\_1\_1\_require\_or\_load’  
/Work/myapp/site/trunk/config/…/vendor/plugins/engines/lib/engines/dependencies\_extensions.rb:14:in  
`require_or_load' /Work/myapp/site/trunk/config/../vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:245:in`load\_missing\_constant’  
/Work/myapp/site/trunk/config/…/vendor/rails/activerecord/lib/…/…/activesupport/lib/active\_support/dependencies.rb:446:in  
`const_missing' /Work/myapp/site/trunk/config/../vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:458:in`const\_missing’  
/Work/myapp/site/trunk/config/…/vendor/rails/activerecord/lib/…/…/activesupport/lib/active\_support/dependencies.rb:257:in  
`load_missing_constant' /Work/myapp/site/trunk/config/../vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:446:in`const\_missing’  
/Work/myapp/site/trunk/config/…/vendor/rails/activerecord/lib/…/…/activesupport/lib/active\_support/dependencies.rb:464:in  
`const_missing' /Work/myapp/site/trunk/config/../vendor/plugins/mail-queue/lib/mail_queue.rb:13:in`deliver!’  
/Work/myapp/site/trunk/config/…/vendor/rails/actionmailer/lib/action\_mailer/base.rb:325:in  
`method_missing' /Work/myapp/site/trunk/config/../app/controllers/estimates_controller.rb:153:in`new’  
/Work/myapp/site/trunk/config/…/vendor/rails/actionpack/lib/action\_controller/base.rb:1068:in  
`perform_action_without_filters' /Work/myapp/site/trunk/config/../vendor/rails/actionpack/lib/action_controller/filters.rb:635:in`call\_filter’  
/Work/myapp/site/trunk/config/…/vendor/rails/actionpack/lib/action\_controller/filters.rb:637:in  
`call_filter' /Work/myapp/site/trunk/config/../vendor/rails/actionpack/lib/action_controller/filters.rb:641:in`call\_filter’  
/Work/myapp/site/trunk/config/…/vendor/rails/actionpack/lib/action\_controller/filters.rb:438:in  
`call' /Work/myapp/site/trunk/config/../vendor/rails/actionpack/lib/action_controller/filters.rb:640:in`call\_filter’  
/Work/myapp/site/trunk/config/…/vendor/rails/actionpack/lib/action\_controller/filters.rb:622:in  
`perform_action_without_benchmark' /Work/myapp/site/trunk/config/../vendor/rails/actionpack/lib/action_controller/benchmarking.rb:66:in`perform\_action\_without\_rescue’  
/usr/local/lib/ruby/1.8/benchmark.rb:293:in `measure' /Work/myapp/site/trunk/config/../vendor/rails/actionpack/lib/action_controller/benchmarking.rb:66:in`perform\_action\_without\_rescue’  
/Work/myapp/site/trunk/config/…/vendor/rails/actionpack/lib/action\_controller/rescue.rb:81:in  
`perform_action' /Work/myapp/site/trunk/config/../vendor/rails/actionpack/lib/action_controller/base.rb:427:in`process\_without\_filters’  
/Work/myapp/site/trunk/config/…/vendor/rails/actionpack/lib/action\_controller/filters.rb:627:in  
`process_without_session_management_support' /Work/myapp/site/trunk/config/../vendor/rails/actionpack/lib/action_controller/session_management.rb:114:in`process’  
/Work/myapp/site/trunk/config/…/vendor/rails/actionpack/lib/action\_controller/base.rb:330:in  
`process' /Work/myapp/site/trunk/config/../vendor/rails/railties/lib/dispatcher.rb:41:in`dispatch’  
/usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/lib/mongrel/rails.rb:84:in  
`process' /usr/local/lib/ruby/1.8/sync.rb:229:in`synchronize’  
/usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/lib/mongrel/rails.rb:83:in  
`process' /usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/lib/mongrel.rb:580:in`process\_client’  
/usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/lib/mongrel.rb:579:in  
`process_client' /usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/lib/mongrel.rb:686:in`run’  
/usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/lib/mongrel.rb:686:in  
`run' /usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/lib/mongrel.rb:673:in`run’  
/usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/lib/mongrel/configurator.rb:267:in  
`run' /usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/lib/mongrel/configurator.rb:266:in`run’  
/usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/bin/mongrel\_rails:127:in  
`run' /usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/lib/mongrel/command.rb:211:in`run’  
/usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/bin/mongrel\_rails:231  
/usr/local/bin/mongrel\_rails:18

---

<div class="post-metadata">

**Author:** ![subimage](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/aca169/32.png) [@subimage](https://www.ruby-forum.com/u/subimage)\
**Post date:** [December 14, 2006, 2:30am UTC](https://www.ruby-forum.com/t/conflict-with-mail-queue-and-engines/79304/2 "2006-12-14T02:30:53Z")

</div>

## Not sure if anyone saw this as I got a rejected mail message from the list server. Apologies if this is a duplicate…

I’m trying to use the Mail Queue plugin from:  
ruby script/plugin install svn://rubyforge.org/var/svn/mail-queue

When I try to deliver an email I’m getting the following stack trace.  
Looks like it’s conflicting with engines, but I can’t be sure. Anyone  
else seen this or know what might be going on?

* * *

You have a nil object when you didn’t expect it!  
You might have expected an instance of Array.  
The error occurred while evaluating nil.empty?

/Work/myapp/site/trunk/config/…/vendor/rails/activerecord/lib/…/…/activesupport/lib/active\_support/dependencies.rb:371:in  
`new_constants_in' /Work/myapp/site/trunk/config/../vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:199:in`load\_file’  
/Work/myapp/site/trunk/config/…/vendor/rails/activerecord/lib/…/…/activesupport/lib/active\_support/dependencies.rb:95:in  
`rails_pre_engines_require_or_load' /Work/myapp/site/trunk/config/../vendor/plugins/engines/lib/engines/dependencies_extensions.rb:60:in`rails\_1\_1\_require\_or\_load’  
/Work/myapp/site/trunk/config/…/vendor/plugins/engines/lib/engines/dependencies\_extensions.rb:14:in  
`require_or_load' /Work/myapp/site/trunk/config/../vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:245:in`load\_missing\_constant’  
/Work/myapp/site/trunk/config/…/vendor/rails/activerecord/lib/…/…/activesupport/lib/active\_support/dependencies.rb:446:in  
`const_missing' /Work/myapp/site/trunk/config/../vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:458:in`const\_missing’  
/Work/myapp/site/trunk/config/…/vendor/rails/activerecord/lib/…/…/activesupport/lib/active\_support/dependencies.rb:257:in  
`load_missing_constant' /Work/myapp/site/trunk/config/../vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb:446:in`const\_missing’  
/Work/myapp/site/trunk/config/…/vendor/rails/activerecord/lib/…/…/activesupport/lib/active\_support/dependencies.rb:464:in  
`const_missing' /Work/myapp/site/trunk/config/../vendor/plugins/mail-queue/lib/mail_queue.rb:13:in`deliver!’  
/Work/myapp/site/trunk/config/…/vendor/rails/actionmailer/lib/action\_mailer/base.rb:325:in  
`method_missing' /Work/myapp/site/trunk/config/../app/controllers/estimates_controller.rb:153:in`new’  
/Work/myapp/site/trunk/config/…/vendor/rails/actionpack/lib/action\_controller/base.rb:1068:in  
`perform_action_without_filters' /Work/myapp/site/trunk/config/../vendor/rails/actionpack/lib/action_controller/filters.rb:635:in`call\_filter’  
/Work/myapp/site/trunk/config/…/vendor/rails/actionpack/lib/action\_controller/filters.rb:637:in  
`call_filter' /Work/myapp/site/trunk/config/../vendor/rails/actionpack/lib/action_controller/filters.rb:641:in`call\_filter’  
/Work/myapp/site/trunk/config/…/vendor/rails/actionpack/lib/action\_controller/filters.rb:438:in  
`call' /Work/myapp/site/trunk/config/../vendor/rails/actionpack/lib/action_controller/filters.rb:640:in`call\_filter’  
/Work/myapp/site/trunk/config/…/vendor/rails/actionpack/lib/action\_controller/filters.rb:622:in  
`perform_action_without_benchmark' /Work/myapp/site/trunk/config/../vendor/rails/actionpack/lib/action_controller/benchmarking.rb:66:in`perform\_action\_without\_rescue’  
/usr/local/lib/ruby/1.8/benchmark.rb:293:in `measure' /Work/myapp/site/trunk/config/../vendor/rails/actionpack/lib/action_controller/benchmarking.rb:66:in`perform\_action\_without\_rescue’  
/Work/myapp/site/trunk/config/…/vendor/rails/actionpack/lib/action\_controller/rescue.rb:81:in  
`perform_action' /Work/myapp/site/trunk/config/../vendor/rails/actionpack/lib/action_controller/base.rb:427:in`process\_without\_filters’  
/Work/myapp/site/trunk/config/…/vendor/rails/actionpack/lib/action\_controller/filters.rb:627:in  
`process_without_session_management_support' /Work/myapp/site/trunk/config/../vendor/rails/actionpack/lib/action_controller/session_management.rb:114:in`process’  
/Work/myapp/site/trunk/config/…/vendor/rails/actionpack/lib/action\_controller/base.rb:330:in  
`process' /Work/myapp/site/trunk/config/../vendor/rails/railties/lib/dispatcher.rb:41:in`dispatch’  
/usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/lib/mongrel/rails.rb:84:in  
`process' /usr/local/lib/ruby/1.8/sync.rb:229:in`synchronize’  
/usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/lib/mongrel/rails.rb:83:in  
`process' /usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/lib/mongrel.rb:580:in`process\_client’  
/usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/lib/mongrel.rb:579:in  
`process_client' /usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/lib/mongrel.rb:686:in`run’  
/usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/lib/mongrel.rb:686:in  
`run' /usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/lib/mongrel.rb:673:in`run’  
/usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/lib/mongrel/configurator.rb:267:in  
`run' /usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/lib/mongrel/configurator.rb:266:in`run’  
/usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/bin/mongrel\_rails:127:in  
`run' /usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/lib/mongrel/command.rb:211:in`run’  
/usr/local/lib/ruby/gems/1.8/gems/mongrel-0.3.13.4/bin/mongrel\_rails:231  
/usr/local/bin/mongrel\_rails:18

---

<div class="post-metadata">

**Author:** ![subimage](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/aca169/32.png) [@subimage](https://www.ruby-forum.com/u/subimage)\
**Post date:** [December 14, 2006, 10:45am UTC](https://www.ruby-forum.com/t/conflict-with-mail-queue-and-engines/79304/3 "2006-12-14T10:45:18Z")

</div>

We’d need to find out what constant Mail Queue is expecting in it’s  
deliver! method, and where engines/Rails is looking to load it from.  
Turning on the engines logger should give some fairly detailed output  
about Rails attempting to load classes.

---

<div class="post-metadata">

**Author:** ![subimage](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/aca169/32.png) [@subimage](https://www.ruby-forum.com/u/subimage)\
**Post date:** [September 26, 2007, 6:27pm UTC](https://www.ruby-forum.com/t/conflict-with-mail-queue-and-engines/79304/4 "2007-09-26T18:27:33Z")

</div>

James S. wrote:

> I thought I would post my ‘fix’ incase anyone runs across this post with  
> the same problem.
> 
> I renamed the mail-queue folder in vendor/plugins to mail\_queue  
> worked for me, as well  
> rename selenium-plugin as selenium\_plugin and voila.

---

<div class="post-metadata">

**Author:** ![subimage](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/aca169/32.png) [@subimage](https://www.ruby-forum.com/u/subimage)\
**Post date:** [April 11, 2007, 10:10pm UTC](https://www.ruby-forum.com/t/conflict-with-mail-queue-and-engines/79304/5 "2007-04-11T22:10:22Z")

</div>

I thought I would post my ‘fix’ incase anyone runs across this post with  
the same problem.

I renamed the mail-queue folder in vendor/plugins to mail\_queue

After the rename everything worked great.

Subimage Interactive wrote:

> I’m trying to use the Mail Queue plugin from:  
> ruby script/plugin install svn://rubyforge.org/var/svn/mail-queue
> 
> When I try to deliver an email I’m getting the following stack trace.  
> Looks like it’s conflicting with engines, but I can’t be sure. Anyone  
> else seen this or know what might be going on?

---

<div class="post-metadata">

**Author:** ![subimage](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/aca169/32.png) [@subimage](https://www.ruby-forum.com/u/subimage)\
**Post date:** [September 26, 2007, 6:30pm UTC](https://www.ruby-forum.com/t/conflict-with-mail-queue-and-engines/79304/6 "2007-09-26T18:30:49Z")

</div>

James S. wrote:

> I thought I would post my ‘fix’ incase anyone runs across this post with  
> the same problem.
> 
> I renamed the mail-queue folder in vendor/plugins to mail\_queue

worked for me, as well  
rename selenium-plugin as selenium\_plugin and voila.

---

<div class="post-metadata">

**Author:** ![subimage](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/aca169/32.png) [@subimage](https://www.ruby-forum.com/u/subimage)\
**Post date:** [October 14, 2007, 12:11pm UTC](https://www.ruby-forum.com/t/conflict-with-mail-queue-and-engines/79304/7 "2007-10-14T12:11:10Z")

</div>

Roger P. wrote:

> James S. wrote:
> 
> > I thought I would post my ‘fix’ incase anyone runs across this post with  
> > the same problem.
> > 
> > I renamed the mail-queue folder in vendor/plugins to mail\_queue
> 
> worked for me, as well  
> rename selenium-plugin as selenium\_plugin and voila.