NoMethodError (undefined method `find_by_uid')

Question

Существует приложение, работающее на Rails 5 beta 4 в режиме API и Angular2. Для авторизации используются Devise + Devise Token Auth.

На локальном сервере в development и production всё работает прекрасно.

Проблемы начинаются с развёртывания на Heroku.

На GET запросу к / получаю следующее:

2016年04月29日T12:22:42.570708+00:00 heroku[router]: at=info method=GET path="/" host=yaktalk.herokuapp.com request_id=79c11e3e-66c3-4380-a641-caae9eaeee8d fwd="109.229.68.244" dyno=web.1 connect=1ms service=3ms status=200 bytes=2514
2016年04月29日T12:22:42.764938+00:00 heroku[router]: at=info method=GET path="/node_modules/tether/dist/js/tether.min.js" host=yaktalk.herokuapp.com request_id=35d65a33-7999-457a-b331-9d4e3299a3ed fwd="109.229.68.244" dyno=web.1 connect=1ms service=3ms status=200 bytes=23453
2016年04月29日T12:22:42.762029+00:00 heroku[router]: at=info method=GET path="/node_modules/tether/dist/css/tether.min.css" host=yaktalk.herokuapp.com request_id=931d24c8-c49c-4e95-a988-ce303175e569 fwd="109.229.68.244" dyno=web.1 connect=1ms service=1ms status=200 bytes=366
2016年04月29日T12:22:42.908337+00:00 heroku[router]: at=info method=GET path="/node_modules/bootstrap/dist/css/bootstrap.min.css" host=yaktalk.herokuapp.com request_id=c4bb11bc-1db4-4310-a087-001fae79b5c5 fwd="109.229.68.244" dyno=web.1 connect=1ms service=7ms status=200 bytes=95694
2016年04月29日T12:22:42.929356+00:00 heroku[router]: at=info method=GET path="/style.css" host=yaktalk.herokuapp.com request_id=37ebb298-fdcd-47e7-bf07-dab15e3c1aac fwd="109.229.68.244" dyno=web.1 connect=1ms service=9ms status=200 bytes=2487
2016年04月29日T12:22:42.923269+00:00 heroku[router]: at=info method=GET path="/node_modules/jquery/dist/jquery.min.js" host=yaktalk.herokuapp.com request_id=14779714-9daf-48f1-94c3-71b4565259de fwd="109.229.68.244" dyno=web.1 connect=0ms service=7ms status=200 bytes=85804
2016年04月29日T12:22:42.930011+00:00 heroku[router]: at=info method=GET path="/node_modules/bootstrap/dist/js/bootstrap.min.js" host=yaktalk.herokuapp.com request_id=db7ddfec-a837-4381-a942-91c2a2a93de9 fwd="109.229.68.244" dyno=web.1 connect=1ms service=7ms status=200 bytes=44971
2016年04月29日T12:22:42.952537+00:00 heroku[router]: at=info method=GET path="/node_modules/angular2/bundles/angular2-polyfills.js" host=yaktalk.herokuapp.com request_id=14d7fcbe-8ee4-4913-8e95-af8df8f8dd61 fwd="109.229.68.244" dyno=web.1 connect=1ms service=12ms status=200 bytes=103859
2016年04月29日T12:22:43.049183+00:00 heroku[router]: at=info method=GET path="/node_modules/systemjs/dist/system.src.js" host=yaktalk.herokuapp.com request_id=dc6d9fa6-af6c-472a-90b3-f321dcbb9397 fwd="109.229.68.244" dyno=web.1 connect=1ms service=9ms status=200 bytes=162534
2016年04月29日T12:22:43.093086+00:00 heroku[router]: at=info method=GET path="/node_modules/rxjs/bundles/Rx.js" host=yaktalk.herokuapp.com request_id=050e5a30-601d-43cc-bd10-855897d60c2b fwd="109.229.68.244" dyno=web.1 connect=1ms service=22ms status=200 bytes=407932
2016年04月29日T12:22:43.462405+00:00 heroku[router]: at=info method=GET path="/node_modules/angular2/bundles/router.dev.js" host=yaktalk.herokuapp.com request_id=96e99e58-a195-40c3-88ec-fb1cc704bbc5 fwd="109.229.68.244" dyno=web.1 connect=1ms service=10ms status=200 bytes=142936
2016年04月29日T12:22:43.381616+00:00 heroku[router]: at=info method=GET path="/node_modules/angular2/bundles/angular2.dev.js" host=yaktalk.herokuapp.com request_id=2c1c27d6-8f3b-4816-b968-939e152b2a7f fwd="109.229.68.244" dyno=web.1 connect=1ms service=40ms status=200 bytes=1095459
2016年04月29日T12:22:43.473473+00:00 heroku[router]: at=info method=GET path="/node_modules/angular2/bundles/http.dev.js" host=yaktalk.herokuapp.com request_id=787a8e3e-f0ba-424f-8a84-874b0e9e58db fwd="109.229.68.244" dyno=web.1 connect=1ms service=6ms status=200 bytes=48996
2016年04月29日T12:22:44.805997+00:00 heroku[router]: at=info method=GET path="/app/main.js" host=yaktalk.herokuapp.com request_id=3cc7bba2-c4fd-4714-80dd-353a897248dc fwd="109.229.68.244" dyno=web.1 connect=1ms service=8ms status=200 bytes=946
2016年04月29日T12:22:44.947382+00:00 heroku[router]: at=info method=GET path="/favicon.ico" host=yaktalk.herokuapp.com request_id=1bf62c43-a871-4500-a931-669a392927b1 fwd="109.229.68.244" dyno=web.1 connect=1ms service=2ms status=200 bytes=143
2016年04月29日T12:22:44.962279+00:00 heroku[router]: at=info method=GET path="/app/app.component.js" host=yaktalk.herokuapp.com request_id=d145388a-704d-4031-9a1b-3a6ed727972f fwd="109.229.68.244" dyno=web.1 connect=1ms service=2ms status=200 bytes=3542
2016年04月29日T12:22:45.410108+00:00 heroku[router]: at=info method=GET path="/app/messages/messages.service.js" host=yaktalk.herokuapp.com request_id=a3c9bbbc-eb83-4e57-8001-f6d9ca41971d fwd="109.229.68.244" dyno=web.1 connect=0ms service=2ms status=200 bytes=3878
2016年04月29日T12:22:45.414038+00:00 heroku[router]: at=info method=GET path="/app/login/login.service.js" host=yaktalk.herokuapp.com request_id=3aacbdc9-1570-4552-bfc8-e6b6d354b029 fwd="109.229.68.244" dyno=web.1 connect=1ms service=2ms status=200 bytes=4180
2016年04月29日T12:22:45.391832+00:00 heroku[router]: at=info method=GET path="/app/messages/messages.component.js" host=yaktalk.herokuapp.com request_id=4bca583c-f7a6-47b4-b9ed-c1c406de2909 fwd="109.229.68.244" dyno=web.1 connect=1ms service=3ms status=200 bytes=4188
2016年04月29日T12:22:45.411166+00:00 heroku[router]: at=info method=GET path="/app/login/login.component.js" host=yaktalk.herokuapp.com request_id=95c2937c-179e-4b14-b31d-2e9bf46dc0fc fwd="109.229.68.244" dyno=web.1 connect=1ms service=3ms status=200 bytes=4099
2016年04月29日T12:22:45.561673+00:00 heroku[router]: at=info method=GET path="/app/user.js" host=yaktalk.herokuapp.com request_id=3a8b9644-b803-4f95-bfba-60873c91d398 fwd="109.229.68.244" dyno=web.1 connect=1ms service=2ms status=200 bytes=879
2016年04月29日T12:22:45.939576+00:00 heroku[router]: at=info method=GET path="/app/app.component.html" host=yaktalk.herokuapp.com request_id=8007e574-818c-4ae3-ac7c-d8a46b75b04a fwd="109.229.68.244" dyno=web.1 connect=1ms service=1ms status=200 bytes=320
2016年04月29日T12:22:46.146029+00:00 heroku[router]: at=info method=GET path="/app/messages/messages.component.html" host=yaktalk.herokuapp.com request_id=4eea0955-b017-44c5-8494-c2bc60367f43 fwd="109.229.68.244" dyno=web.1 connect=1ms service=1ms status=200 bytes=314
2016年04月29日T12:22:46.357210+00:00 heroku[router]: at=info method=GET path="/messages" host=yaktalk.herokuapp.com request_id=b27dcc4b-1e84-4d49-ba85-928c3f60a2f3 fwd="109.229.68.244" dyno=web.1 connect=0ms service=40ms status=500 bytes=1669
2016年04月29日T12:22:46.358307+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] Started GET "/messages" for 109.229.68.244 at 2016年04月29日 12:22:46 +0000
2016年04月29日T12:22:46.361832+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] Processing by MessagesController#show as json
2016年04月29日T12:22:46.368503+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] Completed 500 Internal Server Error in 7ms (ActiveRecord: 2.8ms)
2016年04月29日T12:22:46.369575+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3]
2016年04月29日T12:22:46.369954+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] NoMethodError (undefined method `find_by_uid' for #<Class:0x007fd93e174750>):
2016年04月29日T12:22:46.369988+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3]
2016年04月29日T12:22:46.370017+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activerecord-5.0.0.beta4/lib/active_record/dynamic_matchers.rb:21:in `method_missing'
2016年04月29日T12:22:46.370054+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/bundler/gems/devise_token_auth-10863b31270b/app/controllers/devise_token_auth/concerns/set_user_by_token.rb:61:in `set_user_by_token'
2016年04月29日T12:22:46.370081+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/bundler/gems/devise_token_auth-10863b31270b/lib/devise_token_auth/controllers/helpers.rb:123:in `current_user'
2016年04月29日T12:22:46.370173+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/bundler/gems/devise_token_auth-10863b31270b/lib/devise_token_auth/controllers/helpers.rb:111:in `authenticate_user!'
2016年04月29日T12:22:46.370201+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/callbacks.rb:382:in `block in make_lambda'
2016年04月29日T12:22:46.370236+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/callbacks.rb:169:in `call'
2016年04月29日T12:22:46.370261+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/callbacks.rb:169:in `block (2 levels) in halting'
2016年04月29日T12:22:46.370296+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/abstract_controller/callbacks.rb:12:in `call'
2016年04月29日T12:22:46.370322+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/abstract_controller/callbacks.rb:12:in `block (2 levels) in <module:Callbacks>'
2016年04月29日T12:22:46.370350+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/callbacks.rb:170:in `call'
2016年04月29日T12:22:46.370413+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/callbacks.rb:170:in `block in halting'
2016年04月29日T12:22:46.370446+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/callbacks.rb:454:in `call'
2016年04月29日T12:22:46.370472+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/callbacks.rb:454:in `block in call'
2016年04月29日T12:22:46.370507+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/callbacks.rb:454:in `each'
2016年04月29日T12:22:46.370534+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/callbacks.rb:454:in `call'
2016年04月29日T12:22:46.370590+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/callbacks.rb:101:in `__run_callbacks__'
2016年04月29日T12:22:46.370638+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/callbacks.rb:750:in `_run_process_action_callbacks'
2016年04月29日T12:22:46.370640+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/callbacks.rb:90:in `run_callbacks'
2016年04月29日T12:22:46.370655+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/abstract_controller/callbacks.rb:19:in `process_action'
2016年04月29日T12:22:46.370694+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/action_controller/metal/rescue.rb:31:in `process_action'
2016年04月29日T12:22:46.370709+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/action_controller/metal/instrumentation.rb:32:in `block in process_action'
2016年04月29日T12:22:46.370821+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/notifications.rb:164:in `block in instrument'
2016年04月29日T12:22:46.370836+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/notifications/instrumenter.rb:21:in `instrument'
2016年04月29日T12:22:46.370879+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/notifications.rb:164:in `instrument'
2016年04月29日T12:22:46.370884+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/action_controller/metal/instrumentation.rb:30:in `process_action'
2016年04月29日T12:22:46.370928+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/action_controller/metal/params_wrapper.rb:248:in `process_action'
2016年04月29日T12:22:46.370944+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activerecord-5.0.0.beta4/lib/active_record/railties/controller_runtime.rb:18:in `process_action'
2016年04月29日T12:22:46.370978+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/abstract_controller/base.rb:126:in `process'
2016年04月29日T12:22:46.370992+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/action_controller/metal.rb:190:in `dispatch'
2016年04月29日T12:22:46.371024+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/action_controller/metal.rb:262:in `dispatch'
2016年04月29日T12:22:46.371052+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/action_dispatch/routing/route_set.rb:50:in `dispatch'
2016年04月29日T12:22:46.371087+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/action_dispatch/routing/route_set.rb:32:in `serve'
2016年04月29日T12:22:46.371113+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/action_dispatch/journey/router.rb:39:in `block in serve'
2016年04月29日T12:22:46.371139+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/action_dispatch/journey/router.rb:26:in `each'
2016年04月29日T12:22:46.371207+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/action_dispatch/journey/router.rb:26:in `serve'
2016年04月29日T12:22:46.371234+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/action_dispatch/routing/route_set.rb:725:in `call'
2016年04月29日T12:22:46.371301+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/warden-1.2.6/lib/warden/manager.rb:35:in `block in call'
2016年04月29日T12:22:46.371333+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/warden-1.2.6/lib/warden/manager.rb:34:in `catch'
2016年04月29日T12:22:46.371360+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/warden-1.2.6/lib/warden/manager.rb:34:in `call'
2016年04月29日T12:22:46.371388+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/rack-2.0.0.alpha/lib/rack/etag.rb:25:in `call'
2016年04月29日T12:22:46.371413+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/rack-2.0.0.alpha/lib/rack/conditional_get.rb:25:in `call'
2016年04月29日T12:22:46.371482+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/rack-2.0.0.alpha/lib/rack/head.rb:12:in `call'
2016年04月29日T12:22:46.371499+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/action_dispatch/middleware/callbacks.rb:38:in `block in call'
2016年04月29日T12:22:46.371533+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/callbacks.rb:97:in `__run_callbacks__'
2016年04月29日T12:22:46.371583+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/callbacks.rb:750:in `_run_call_callbacks'
2016年04月29日T12:22:46.371610+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/callbacks.rb:90:in `run_callbacks'
2016年04月29日T12:22:46.371638+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/action_dispatch/middleware/callbacks.rb:36:in `call'
2016年04月29日T12:22:46.371684+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/action_dispatch/middleware/remote_ip.rb:79:in `call'
2016年04月29日T12:22:46.371704+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/action_dispatch/middleware/debug_exceptions.rb:49:in `call'
2016年04月29日T12:22:46.371718+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/action_dispatch/middleware/show_exceptions.rb:31:in `call'
2016年04月29日T12:22:46.371754+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/railties-5.0.0.beta4/lib/rails/rack/logger.rb:36:in `call_app'
2016年04月29日T12:22:46.371774+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/railties-5.0.0.beta4/lib/rails/rack/logger.rb:24:in `block in call'
2016年04月29日T12:22:46.371791+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/tagged_logging.rb:70:in `block in tagged'
2016年04月29日T12:22:46.371823+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/tagged_logging.rb:26:in `tagged'
2016年04月29日T12:22:46.371856+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/tagged_logging.rb:70:in `tagged'
2016年04月29日T12:22:46.371875+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/railties-5.0.0.beta4/lib/rails/rack/logger.rb:24:in `call'
2016年04月29日T12:22:46.371907+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/action_dispatch/middleware/request_id.rb:24:in `call'
2016年04月29日T12:22:46.371927+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/rack-2.0.0.alpha/lib/rack/runtime.rb:22:in `call'
2016年04月29日T12:22:46.371946+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/cache/strategy/local_cache_middleware.rb:28:in `call'
2016年04月29日T12:22:46.371977+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/action_dispatch/middleware/executor.rb:12:in `call'
2016年04月29日T12:22:46.372014+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/actionpack-5.0.0.beta4/lib/action_dispatch/middleware/static.rb:136:in `call'
2016年04月29日T12:22:46.372030+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/rack-2.0.0.alpha/lib/rack/sendfile.rb:111:in `call'
2016年04月29日T12:22:46.372061+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/railties-5.0.0.beta4/lib/rails/engine.rb:522:in `call'
2016年04月29日T12:22:46.372082+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/puma-3.4.0/lib/puma/configuration.rb:224:in `call'
2016年04月29日T12:22:46.372101+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/puma-3.4.0/lib/puma/server.rb:569:in `handle_request'
2016年04月29日T12:22:46.372120+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/puma-3.4.0/lib/puma/server.rb:406:in `process_client'
2016年04月29日T12:22:46.372159+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/puma-3.4.0/lib/puma/server.rb:271:in `block in run'
2016年04月29日T12:22:46.372178+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/puma-3.4.0/lib/puma/thread_pool.rb:114:in `call'
2016年04月29日T12:22:46.372231+00:00 app[web.1]: [b27dcc4b-1e84-4d49-ba85-928c3f60a2f3] vendor/bundle/ruby/2.2.0/gems/puma-3.4.0/lib/puma/thread_pool.rb:114:in `block in spawn_thread'
2016年04月29日T12:23:05.993904+00:00 app[web.1]: [7cf80123-2e44-4901-839d-7b129cd53bd1] Started DELETE "/auth/sign_out" for 109.229.68.244 at 2016年04月29日 12:23:05 +0000
2016年04月29日T12:23:05.997085+00:00 app[web.1]: [7cf80123-2e44-4901-839d-7b129cd53bd1] Processing by Overrides::SessionsController#destroy as json
2016年04月29日T12:23:05.999668+00:00 app[web.1]: [7cf80123-2e44-4901-839d-7b129cd53bd1] Completed 500 Internal Server Error in 2ms (ActiveRecord: 0.0ms)
2016年04月29日T12:23:06.000859+00:00 app[web.1]: [7cf80123-2e44-4901-839d-7b129cd53bd1]
2016年04月29日T12:23:06.001059+00:00 app[web.1]: [7cf80123-2e44-4901-839d-7b129cd53bd1] NoMethodError (undefined method `find_by_uid' for #<Class:0x007fd93e174750>):
2016年04月29日T12:23:06.001126+00:00 app[web.1]: [7cf80123-2e44-4901-839d-7b129cd53bd1]
2016年04月29日T12:23:06.001154+00:00 app[web.1]: [7cf80123-2e44-4901-839d-7b129cd53bd1] vendor/bundle/ruby/2.2.0/gems/activerecord-5.0.0.beta4/lib/active_record/dynamic_matchers.rb:21:in `method_missing'
2016年04月29日T12:23:06.001181+00:00 app[web.1]: [7cf80123-2e44-4901-839d-7b129cd53bd1] vendor/bundle/ruby/2.2.0/bundler/gems/devise_token_auth-10863b31270b/app/controllers/devise_token_auth/concerns/set_user_by_token.rb:61:in `set_user_by_token'
2016年04月29日T12:23:06.001207+00:00 app[web.1]: [7cf80123-2e44-4901-839d-7b129cd53bd1] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/callbacks.rb:382:in `block in make_lambda'
2016年04月29日T12:23:06.001268+00:00 app[web.1]: [7cf80123-2e44-4901-839d-7b129cd53bd1] vendor/bundle/ruby/2.2.0/gems/activesupport-5.0.0.beta4/lib/active_support/callbacks.rb:150:in `call'

Сразу бросается в глаза NoMethodError (undefined method 'find_by_uid' for #<Class:0x007fd93e174750>). find_by_uid -- метод, принадлежащий гему devise_token_auth. Что самое интересное, в development он работает прекрасно. Вот тест метода в консоли:

development:

 irb(main):001:0> User.find_by_uid('demo')
 User Load (1.0ms) SELECT "users".* FROM "users" WHERE "users"."uid" = 1ドル LIMIT 2ドル [["uid", "demo"], ["LIMIT", 1]]
 => #<User id: 2, provider: "username", uid: "demo"...

production:

irb(main):003:0* User.find_by_uid('demo')
NoMethodError: undefined method `find_by_uid' for #<Class:0x007f6b5de1b020>
 from /app/vendor/bundle/ruby/2.2.0/gems/activerecord-5.0.0.beta4/lib/active_record/dynamic_matchers.rb:21:in `method_missing'
 from (irb):3
 from /app/vendor/bundle/ruby/2.2.0/gems/railties-5.0.0.beta4/lib/rails/commands/console.rb:65:in `start'
 from /app/vendor/bundle/ruby/2.2.0/gems/railties-5.0.0.beta4/lib/rails/commands/console_helper.rb:9:in `start'
 from /app/vendor/bundle/ruby/2.2.0/gems/railties-5.0.0.beta4/lib/rails/commands/commands_tasks.rb:78:in `console'
 from /app/vendor/bundle/ruby/2.2.0/gems/railties-5.0.0.beta4/lib/rails/commands/commands_tasks.rb:49:in `run_command!'
 from /app/vendor/bundle/ruby/2.2.0/gems/railties-5.0.0.beta4/lib/rails/commands.rb:18:in `<top (required)>'
 from bin/rails:9:in `require'
 from bin/rails:9:in `<main>

---

UPD #1:

Я провёл небольшое исследование. В общем, смотрите сами:

Локальный сервер

irb(main):004:0> User.first
 User Load (0.5ms) SELECT "users".* FROM "users" ORDER BY "users"."id" ASC LIMIT 1ドル [["LIMIT", 1]]
=> #<User id: 1, provider: "username", uid: "duke", encrypted_password: "2ドルa11ドル$zDviguprmYVa4SIZ1EDCE.2k9Ubbv7yOxtKuHOuxmjS...", reset_password_token: nil, reset_password_sent_at: nil, remember_created_at: nil, sign_in_count: 0, current_sign_in_at: nil, last_si
gn_in_at: nil, current_sign_in_ip: nil, last_sign_in_ip: nil, name: "Viktor", username: "duke", avatar: nil, tokens: {}, created_at: "2016-04-30 07:03:51", updated_at: "2016-04-30 07:03:51">

Heroku

irb(main):003:0* User.first
 User Load (3.9ms) SELECT "users".* FROM "users" ORDER BY "users"."id" ASC LIMIT 1ドル [["LIMIT", 1]]
=> #<User id: 1, name: "John Demo", username: "demo", encrypted_password: "2ドルa11ドル$JR9WpVBwFIre/p/Q0kYnt.mrwIShjZGZEoS2KTboFWS...", reset_password_token: nil, reset_password_sent_at: nil, remember_created_at: nil, sign_in_count: 0, current_sign_in_at: nil, last_sign_in_at: nil, current_sign_in_ip: nil, last_sign_in_ip: nil, created_at: "2016-04-13 15:44:39", updated_at: "2016-04-13 15:44:39">

На Heroku в моей модели просто отсутствуют все атрибуты, получаемые от devise_token_auth, что приводит меня к мысли -- от просто не работает.

Я подозреваю, что проблема кроется в том, что я использую гем напрямую из репозитория (и вот почему)

gem 'devise_token_auth', github:"lynndylanhurley/devise_token_auth", branch: "master"

Хоть он и устанавливается во время развёртывания (см. build log), он всё равно ведёт себя так, словно его нет.

Build log

...
Using devise_token_auth 0.1.37 from git://github.com/lynndylanhurley/devise_token_auth.git (at master@10863b3)
...

• cheops: А в продакшене User.class что возвращает?
• cheops: Я не говорю, что это проблема, просто пока даже не понятно в какую сторону рыть. Попробуйте еще вот что, возьмите последний объект класса и посмотрите его методы User.last.methods.sort.each{|x| puts x }; nil; возможно там будет какая-то дополнительная информация для размышления, почему так происходит.
• user181100: @cheops эм, что? О_о User, как класс модели, имеет тип Class, без вариантов.
• user181100: Попробуйте в девелопменте и в продакшене посмотреть на вывод User.columns.map {|x|[x.name, x.sql_type]}
• user181100: Эта шутка как раз выводит столбцы в реальной таблице :) Опишите, хуже не будет. Эти методы (dynamic finders) как раз генерируются по набору столбцов в таблице, и их может не быть, если столбцов не хватает. Этот факт указан в документации, но неплохо бы зафиксировать и тут.