+++ This bug was initially created as a clone of Bug #840969 +++

Description of problem:
As a sysadmin I should not be able to delete an environment with user members (users that have the environment set has their default).

Deleting an environment where users have set the environment as their default will lead to the environments tab under user preferences being inaccessible.

Version-Release number of selected component (if applicable):
sam-1.1

Steps to Reproduce:
1. Create environments under an org
2. Navigate to user preferences
3. Navigate to the Environments tab under user preferences
4. Assign the default org and environment as set up in step 1.
5. Return to the orgs tab
6. delete the environment set in step 1.
7. Return to user preferences
8. select user and navigate to environments tab
  
Actual results:
Tab is inaccessible.

---production.log
[ERROR: 2012-07-17 13:56:27 #12589] ActiveRecord::RecordNotFound: Couldn't find KTEnvironment with ID=2
/usr/lib/ruby/gems/1.8/gems/activerecord-3.0.10/lib/active_record/relation/finder_methods.rb:304:in `find_one'
/usr/lib/ruby/gems/1.8/gems/activerecord-3.0.10/lib/active_record/relation/finder_methods.rb:289:in `find_with_ids'
/usr/lib/ruby/gems/1.8/gems/activerecord-3.0.10/lib/active_record/relation/finder_methods.rb:107:in `find'
/usr/lib/ruby/gems/1.8/gems/activerecord-3.0.10/lib/active_record/base.rb:444:in `__send__'
/usr/lib/ruby/gems/1.8/gems/activerecord-3.0.10/lib/active_record/base.rb:444:in `find'
/usr/share/katello/app/models/user.rb:438:in `default_environment'
/usr/share/katello/app/models/user.rb:508:in `as_json'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/json/encoding.rb:54:in `as_json'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/json/encoding.rb:77:in `check_for_circular_references'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/json/encoding.rb:53:in `as_json'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/json/encoding.rb:209:in `as_json'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/json/encoding.rb:209:in `map'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/json/encoding.rb:209:in `as_json'
/usr/lib/ruby/gems/1.8/gems/activerecord-3.0.10/lib/active_record/relation.rb:80:in `as_json'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/json/encoding.rb:46:in `encode'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/json/encoding.rb:77:in `check_for_circular_references'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/json/encoding.rb:45:in `encode'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/json/encoding.rb:30:in `encode'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/core_ext/object/to_json.rb:15:in `to_json'
/usr/share/katello/app/controllers/api/users_controller.rb:51:in `index'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_controller/metal/implicit_render.rb:4:in `send_action'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_controller/metal/implicit_render.rb:4:in `send_action'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/abstract_controller/base.rb:150:in `process_action'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_controller/metal/rendering.rb:11:in `process_action'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/abstract_controller/callbacks.rb:18:in `process_action'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/callbacks.rb:462:in `_run__1161174178__process_action__199225275__callbacks'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/callbacks.rb:221:in `_conditional_callback_around_2770'
/usr/share/katello/lib/util/threadsession.rb:79:in `thread_locals'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/callbacks.rb:220:in `_conditional_callback_around_2770'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/callbacks.rb:446:in `_run__1161174178__process_action__199225275__callbacks'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/callbacks.rb:410:in `send'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/callbacks.rb:410:in `_run_process_action_callbacks'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/callbacks.rb:94:in `send'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/callbacks.rb:94:in `run_callbacks'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/abstract_controller/callbacks.rb:17:in `process_action'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_controller/metal/rescue.rb:17:in `process_action'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_controller/metal/instrumentation.rb:30:in `process_action'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/notifications.rb:52:in `instrument'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/notifications/instrumenter.rb:21:in `instrument'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/notifications.rb:52:in `instrument'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_controller/metal/instrumentation.rb:29:in `process_action'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/abstract_controller/base.rb:119:in `process'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/abstract_controller/rendering.rb:41:in `process'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_controller/metal.rb:138:in `dispatch'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_controller/metal/rack_delegation.rb:14:in `dispatch'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_controller/metal.rb:178:in `action'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_dispatch/routing/route_set.rb:62:in `call'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_dispatch/routing/route_set.rb:62:in `dispatch'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_dispatch/routing/route_set.rb:27:in `call'
/usr/lib/ruby/gems/1.8/gems/rack-mount-0.7.1/lib/rack/mount/route_set.rb:150:in `call'
/usr/lib/ruby/gems/1.8/gems/rack-mount-0.7.1/lib/rack/mount/code_generation.rb:93:in `recognize'
/usr/lib/ruby/gems/1.8/gems/rack-mount-0.7.1/lib/rack/mount/code_generation.rb:117:in `optimized_each'
/usr/lib/ruby/gems/1.8/gems/rack-mount-0.7.1/lib/rack/mount/code_generation.rb:92:in `recognize'
/usr/lib/ruby/gems/1.8/gems/rack-mount-0.7.1/lib/rack/mount/route_set.rb:141:in `call'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_dispatch/routing/route_set.rb:493:in `call'
/usr/lib/ruby/gems/1.8/gems/warden-1.0.5/lib/warden/manager.rb:35:in `call'
/usr/lib/ruby/gems/1.8/gems/warden-1.0.5/lib/warden/manager.rb:34:in `catch'
/usr/lib/ruby/gems/1.8/gems/warden-1.0.5/lib/warden/manager.rb:34:in `call'
/usr/lib/ruby/gems/1.8/gems/sass-3.1.4/lib/sass/../sass/plugin/rack.rb:54:in `call'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_dispatch/middleware/best_standards_support.rb:17:in `call'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_dispatch/middleware/head.rb:14:in `call'
/usr/lib/ruby/gems/1.8/gems/rack-1.3.0/lib/rack/methodoverride.rb:24:in `call'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_dispatch/middleware/params_parser.rb:21:in `call'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_dispatch/middleware/flash.rb:182:in `call'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_dispatch/middleware/session/abstract_store.rb:149:in `call'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_dispatch/middleware/cookies.rb:302:in `call'
/usr/lib/ruby/gems/1.8/gems/activerecord-3.0.10/lib/active_record/query_cache.rb:32:in `call'
/usr/lib/ruby/gems/1.8/gems/activerecord-3.0.10/lib/active_record/connection_adapters/abstract/query_cache.rb:28:in `cache'
/usr/lib/ruby/gems/1.8/gems/activerecord-3.0.10/lib/active_record/query_cache.rb:12:in `cache'
/usr/lib/ruby/gems/1.8/gems/activerecord-3.0.10/lib/active_record/query_cache.rb:31:in `call'
/usr/lib/ruby/gems/1.8/gems/activerecord-3.0.10/lib/active_record/connection_adapters/abstract/connection_pool.rb:354:in `call'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_dispatch/middleware/callbacks.rb:46:in `call'
/usr/lib/ruby/gems/1.8/gems/activesupport-3.0.10/lib/active_support/callbacks.rb:416:in `_run_call_callbacks'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_dispatch/middleware/callbacks.rb:44:in `call'
/usr/lib/ruby/gems/1.8/gems/rack-1.3.0/lib/rack/sendfile.rb:102:in `call'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_dispatch/middleware/remote_ip.rb:48:in `call'
/usr/lib/ruby/gems/1.8/gems/actionpack-3.0.10/lib/action_dispatch/middleware/show_exceptions.rb:47:in `call'
/usr/lib/ruby/gems/1.8/gems/railties-3.0.10/lib/rails/rack/logger.rb:13:in `call'
/usr/lib/ruby/gems/1.8/gems/rack-1.3.0/lib/rack/runtime.rb:17:in `call'
/usr/lib/ruby/gems/1.8/gems/rack-1.3.0/lib/rack/lock.rb:34:in `call'
/usr/lib/ruby/gems/1.8/gems/railties-3.0.10/lib/rails/application.rb:168:in `call'
/usr/lib/ruby/gems/1.8/gems/railties-3.0.10/lib/rails/application.rb:77:in `send'
/usr/lib/ruby/gems/1.8/gems/railties-3.0.10/lib/rails/application.rb:77:in `method_missing'
/usr/lib/ruby/gems/1.8/gems/rack-1.3.0/lib/rack/urlmap.rb:52:in `call'
/usr/lib/ruby/gems/1.8/gems/rack-1.3.0/lib/rack/urlmap.rb:46:in `each'
/usr/lib/ruby/gems/1.8/gems/rack-1.3.0/lib/rack/urlmap.rb:46:in `call'
/usr/lib/ruby/gems/1.8/gems/thin-1.2.11/lib/thin/connection.rb:84:in `pre_process'
/usr/lib/ruby/gems/1.8/gems/thin-1.2.11/lib/thin/connection.rb:82:in `catch'
/usr/lib/ruby/gems/1.8/gems/thin-1.2.11/lib/thin/connection.rb:82:in `pre_process'
/usr/lib/ruby/gems/1.8/gems/thin-1.2.11/lib/thin/connection.rb:57:in `process'
/usr/lib/ruby/gems/1.8/gems/thin-1.2.11/lib/thin/connection.rb:42:in `receive_data'
/usr/lib/ruby/gems/1.8/gems/eventmachine-0.12.10/lib/eventmachine.rb:256:in `run_machine'
/usr/lib/ruby/gems/1.8/gems/eventmachine-0.12.10/lib/eventmachine.rb:256:in `run'
/usr/lib/ruby/gems/1.8/gems/thin-1.2.11/lib/thin/backends/base.rb:61:in `start'
/usr/lib/ruby/gems/1.8/gems/thin-1.2.11/lib/thin/server.rb:159:in `start'
/usr/lib/ruby/gems/1.8/gems/thin-1.2.11/lib/thin/controllers/controller.rb:86:in `start'
/usr/lib/ruby/gems/1.8/gems/thin-1.2.11/lib/thin/runner.rb:185:in `send'
/usr/lib/ruby/gems/1.8/gems/thin-1.2.11/lib/thin/runner.rb:185:in `run_command'
/usr/lib/ruby/gems/1.8/gems/thin-1.2.11/lib/thin/runner.rb:151:in `run!'
/usr/lib/ruby/gems/1.8/gems/thin-1.2.11/bin/thin:6
/usr/share/katello/script/thin:24:in `load'
/usr/share/katello/script/thin:24


Expected results:
One of two things:

1. Navigation to the environments tab should succeed and the users defaults should be None allowing for the user's default org and environment to be updated.

or

2. _IF_ an environment has been assigned as the default environment to any number of users any attempt to delete that environment should fail with a warning, "You tried to delete and environment where users are defined."

Additional info:

--- Additional comment from esammons on 2012-07-17 14:00:32 EDT ---

attempt to work-a-round this issue failed.


sam> user update --username admin --no_default_environment
Couldn't find KTEnvironment with ID=2

--- Additional comment from jomara on 2012-08-07 14:58:07 EDT ---

https://github.com/Katello/katello/pull/433

now, when you delete an environment, if a user has it set to his default it becomes unset. the next time he logs in, he is notified of htis