I have a recently started project where i'm using mongoid for the database and rails_admin to manage it, now i want to have an api and i've choosed rails-api to do it, but for some reason since i just added rails-api to the gem file, i can't access to the admin and i'm getting always this error
NoMethodError in Devise::SessionsController#new
undefined method `[]' for nil:NilClass
and here is the trace
warden (1.1.1) lib/warden/session_serializer.rb:29:in fetch'
warden (1.1.1) lib/warden/proxy.rb:196:in
user'
warden (1.1.1) lib/warden/proxy.rb:293:in _perform_authentication'
warden (1.1.1) lib/warden/proxy.rb:90:in
authenticate'
warden (1.1.1) lib/warden/proxy.rb:100:in authenticate?'
devise (2.1.0) app/controllers/devise_controller.rb:113:in
require_no_authentication'
activesupport (3.2.5) lib/active_support/callbacks.rb:407:in _run__3280997315660744487__process_action__4533000551616940901__callbacks'
activesupport (3.2.5) lib/active_support/callbacks.rb:405:in
__run_callback'
activesupport (3.2.5) lib/active_support/callbacks.rb:385:in _run_process_action_callbacks'
activesupport (3.2.5) lib/active_support/callbacks.rb:81:in
run_callbacks'
actionpack (3.2.5) lib/abstract_controller/callbacks.rb:17:in process_action'
actionpack (3.2.5) lib/action_controller/metal/rescue.rb:29:in
process_action'
actionpack (3.2.5) lib/action_controller/metal/instrumentation.rb:30:in block in process_action'
activesupport (3.2.5) lib/active_support/notifications.rb:123:in
block in instrument'
activesupport (3.2.5) lib/active_support/notifications/instrumenter.rb:20:in instrument'
activesupport (3.2.5) lib/active_support/notifications.rb:123:in
instrument'
actionpack (3.2.5) lib/action_controller/metal/instrumentation.rb:29:in process_action'
actionpack (3.2.5) lib/action_controller/metal/params_wrapper.rb:206:in
process_action'
actionpack (3.2.5) lib/abstract_controller/base.rb:121:in process'
actionpack (3.2.5) lib/abstract_controller/rendering.rb:45:in
process'
actionpack (3.2.5) lib/action_controller/metal.rb:203:in dispatch'
actionpack (3.2.5) lib/action_controller/metal/rack_delegation.rb:14:in
dispatch'
actionpack (3.2.5) lib/action_controller/metal.rb:246:in block in action'
actionpack (3.2.5) lib/action_dispatch/routing/route_set.rb:73:in
call'
actionpack (3.2.5) lib/action_dispatch/routing/route_set.rb:73:in dispatch'
actionpack (3.2.5) lib/action_dispatch/routing/route_set.rb:36:in
call'
actionpack (3.2.5) lib/action_dispatch/routing/mapper.rb:42:in call'
journey (1.0.3) lib/journey/router.rb:68:in
block in call'
journey (1.0.3) lib/journey/router.rb:56:in each'
journey (1.0.3) lib/journey/router.rb:56:in
call'
actionpack (3.2.5) lib/action_dispatch/routing/route_set.rb:600:in call'
rack-pjax (0.5.9) lib/rack/pjax.rb:12:in
call'
mongoid (2.4.10) lib/rack/mongoid/middleware/identity_map.rb:33:in block in call'
mongoid (2.4.10) lib/mongoid.rb:133:in
unit_of_work'
mongoid (2.4.10) lib/rack/mongoid/middleware/identity_map.rb:33:in call'
warden (1.1.1) lib/warden/manager.rb:35:in
block in call'
warden (1.1.1) lib/warden/manager.rb:34:in catch'
warden (1.1.1) lib/warden/manager.rb:34:in
call'
rack (1.4.1) lib/rack/etag.rb:23:in call'
rack (1.4.1) lib/rack/conditionalget.rb:25:in
call'
actionpack (3.2.5) lib/action_dispatch/middleware/head.rb:14:in call'
remotipart (1.0.2) lib/remotipart/middleware.rb:30:in
call'
actionpack (3.2.5) lib/action_dispatch/middleware/params_parser.rb:21:in call'
actionpack (3.2.5) lib/action_dispatch/middleware/callbacks.rb:28:in
block in call'
activesupport (3.2.5) lib/active_support/callbacks.rb:405:in _run__2911892753477349565__call__1112249857594481255__callbacks'
activesupport (3.2.5) lib/active_support/callbacks.rb:405:in
__run_callback'
activesupport (3.2.5) lib/active_support/callbacks.rb:385:in _run_call_callbacks'
activesupport (3.2.5) lib/active_support/callbacks.rb:81:in
run_callbacks'
actionpack (3.2.5) lib/action_dispatch/middleware/callbacks.rb:27:in call'
actionpack (3.2.5) lib/action_dispatch/middleware/reloader.rb:65:in
call'
actionpack (3.2.5) lib/action_dispatch/middleware/remote_ip.rb:31:in call'
actionpack (3.2.5) lib/action_dispatch/middleware/debug_exceptions.rb:16:in
call'
actionpack (3.2.5) lib/action_dispatch/middleware/show_exceptions.rb:56:in call'
railties (3.2.5) lib/rails/rack/logger.rb:26:in
call_app'
railties (3.2.5) lib/rails/rack/logger.rb:16:in call'
actionpack (3.2.5) lib/action_dispatch/middleware/request_id.rb:22:in
call'
rack (1.4.1) lib/rack/runtime.rb:17:in call'
activesupport (3.2.5) lib/active_support/cache/strategy/local_cache.rb:72:in
call'
rack (1.4.1) lib/rack/lock.rb:15:in call'
actionpack (3.2.5) lib/action_dispatch/middleware/static.rb:62:in
call'
railties (3.2.5) lib/rails/engine.rb:479:in call'
railties (3.2.5) lib/rails/application.rb:220:in
call'
rack (1.4.1) lib/rack/content_length.rb:14:in call'
railties (3.2.5) lib/rails/rack/log_tailer.rb:17:in
call'
rack (1.4.1) lib/rack/handler/webrick.rb:59:in `service'
i really don't have idea what is happening between those gems that cause this, any advise or direction is welcome ;)