title: how to solve this uninitialized constant UsersController::LinkedIn?
body: <p>after successful verification from LinkedIn i forward to this controller and i get the </p>
  
  <p>uninitialized constant UsersController::LinkedIn</p>
  
  <p>this is where the control goes once the authentication is successful. </p>
  
  <pre><code>class UsersController &lt; ApplicationController
    def index
      # get your api keys at https://www.linkedin.com/secure/developer
      client = LinkedIn::Client.new("ddddd", "eeeee")
      request_token = client.request_token(:oauth_callback =&gt;"http://localhost:3000/users/callback")
      session[:rtoken] = request_token.token
      session[:rsecret] = request_token.secret
      redirect_to client.request_token.authorize_url
    end
  
    def callback
      client = LinkedIn::Client.new("dddd", "eeeeee")
      if session[:atoken].nil?
        pin = params[:oauth_verifier]
        atoken, asecret = client.authorize_from_request(session[:rtoken], session[:rsecret], pin)
        session[:atoken] = atoken
        session[:asecret] = asecret
      else
        client.authorize_from_access(session[:atoken], session[:asecret])
      end
      @profile = client.profile
      @connections = client.connections
    end
  end
  </code></pre>
  
  <p>Full Trace:</p>
  
  <pre><code>pp/controllers/users_controller.rb:4:in `index'
  actionpack (3.2.1) lib/action_controller/metal/implicit_render.rb:4:in `send_action'
  actionpack (3.2.1) lib/action_controller/metal/implicit_render.rb:4:in `send_action'
  actionpack (3.2.1) lib/abstract_controller/base.rb:167:in `process_action'
  actionpack (3.2.1) lib/action_controller/metal/rendering.rb:10:in `process_action'
  actionpack (3.2.1) lib/abstract_controller/callbacks.rb:18:in `process_action'
  activesupport (3.2.1) lib/active_support/callbacks.rb:414:in `_run__434435962__process_action__199225275__callbacks'
  activesupport (3.2.1) lib/active_support/callbacks.rb:405:in `send'
  activesupport (3.2.1) lib/active_support/callbacks.rb:405:in `__run_callback'
  activesupport (3.2.1) lib/active_support/callbacks.rb:385:in `_run_process_action_callbacks'
  activesupport (3.2.1) lib/active_support/callbacks.rb:81:in `send'
  activesupport (3.2.1) lib/active_support/callbacks.rb:81:in `run_callbacks'
  actionpack (3.2.1) lib/abstract_controller/callbacks.rb:17:in `process_action'
  actionpack (3.2.1) lib/action_controller/metal/rescue.rb:29:in `process_action'
  actionpack (3.2.1) lib/action_controller/metal/instrumentation.rb:30:in `process_action'
  activesupport (3.2.1) lib/active_support/notifications.rb:123:in `instrument'
  activesupport (3.2.1) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
  activesupport (3.2.1) lib/active_support/notifications.rb:123:in `instrument'
  actionpack (3.2.1) lib/action_controller/metal/instrumentation.rb:29:in `process_action'
  actionpack (3.2.1) lib/action_controller/metal/params_wrapper.rb:205:in `process_action'
  activerecord (3.2.1) lib/active_record/railties/controller_runtime.rb:18:in `process_action'
  actionpack (3.2.1) lib/abstract_controller/base.rb:121:in `process'
  actionpack (3.2.1) lib/abstract_controller/rendering.rb:45:in `process'
  actionpack (3.2.1) lib/action_controller/metal.rb:203:in `dispatch'
  actionpack (3.2.1) lib/action_controller/metal/rack_delegation.rb:14:in `dispatch'
  actionpack (3.2.1) lib/action_controller/metal.rb:246:in `action'
  actionpack (3.2.1) lib/action_dispatch/routing/route_set.rb:66:in `call'
  actionpack (3.2.1) lib/action_dispatch/routing/route_set.rb:66:in `dispatch'
  actionpack (3.2.1) lib/action_dispatch/routing/route_set.rb:30:in `call'
  journey (1.0.3) lib/journey/router.rb:68: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 (3.2.1) lib/action_dispatch/routing/route_set.rb:589:in `call'
  omniauth (1.0.3) lib/omniauth/strategy.rb:168:in `call!'
  omniauth (1.0.3) lib/omniauth/strategy.rb:148:in `call'
  omniauth (1.0.3) lib/omniauth/builder.rb:42:in `call'
  actionpack (3.2.1) lib/action_dispatch/middleware/best_standards_support.rb:17: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 (3.2.1) lib/action_dispatch/middleware/head.rb:14:in `call'
  actionpack (3.2.1) lib/action_dispatch/middleware/params_parser.rb:21:in `call'
  actionpack (3.2.1) lib/action_dispatch/middleware/flash.rb:242:in `call'
  rack (1.4.1) lib/rack/session/abstract/id.rb:205:in `context'
  rack (1.4.1) lib/rack/session/abstract/id.rb:200:in `call'
  actionpack (3.2.1) lib/action_dispatch/middleware/cookies.rb:338:in `call'
  activerecord (3.2.1) lib/active_record/query_cache.rb:64:in `call'
  activerecord (3.2.1) lib/active_record/connection_adapters/abstract/connection_pool.rb:443:in `call'
  actionpack (3.2.1) lib/action_dispatch/middleware/callbacks.rb:28:in `call'
  activesupport (3.2.1) lib/active_support/callbacks.rb:405:in `_run__397314981__call__4__callbacks'
  activesupport (3.2.1) lib/active_support/callbacks.rb:405:in `send'
  activesupport (3.2.1) lib/active_support/callbacks.rb:405:in `__run_callback'
  activesupport (3.2.1) lib/active_support/callbacks.rb:385:in `_run_call_callbacks'
  activesupport (3.2.1) lib/active_support/callbacks.rb:81:in `send'
  activesupport (3.2.1) lib/active_support/callbacks.rb:81:in `run_callbacks'
  actionpack (3.2.1) lib/action_dispatch/middleware/callbacks.rb:27:in `call'
  actionpack (3.2.1) lib/action_dispatch/middleware/reloader.rb:65:in `call'
  actionpack (3.2.1) lib/action_dispatch/middleware/remote_ip.rb:31:in `call'
  actionpack (3.2.1) lib/action_dispatch/middleware/debug_exceptions.rb:16:in `call'
  actionpack (3.2.1) lib/action_dispatch/middleware/show_exceptions.rb:56:in `call'
  railties (3.2.1) lib/rails/rack/logger.rb:26:in `call_app'
  railties (3.2.1) lib/rails/rack/logger.rb:16:in `call'
  actionpack (3.2.1) lib/action_dispatch/middleware/request_id.rb:22:in `call'
  rack (1.4.1) lib/rack/methodoverride.rb:21:in `call'
  rack (1.4.1) lib/rack/runtime.rb:17:in `call'
  activesupport (3.2.1) lib/active_support/cache/strategy/local_cache.rb:72:in `call'
  rack (1.4.1) lib/rack/lock.rb:15:in `call'
  actionpack (3.2.1) lib/action_dispatch/middleware/static.rb:53:in `call'
  railties (3.2.1) lib/rails/engine.rb:479:in `call'
  railties (3.2.1) lib/rails/application.rb:220:in `call'
  rack (1.4.1) lib/rack/content_length.rb:14:in `call'
  railties (3.2.1) lib/rails/rack/log_tailer.rb:14:in `call'
  rack (1.4.1) lib/rack/handler/webrick.rb:59:in `service'
  C:/RailsInstaller/Ruby1.8.7/lib/ruby/1.8/webrick/httpserver.rb:104:in `service'
  C:/RailsInstaller/Ruby1.8.7/lib/ruby/1.8/webrick/httpserver.rb:65:in `run'
  C:/RailsInstaller/Ruby1.8.7/lib/ruby/1.8/webrick/server.rb:173:in `start_thread'
  C:/RailsInstaller/Ruby1.8.7/lib/ruby/1.8/webrick/server.rb:162:in `start'
  C:/RailsInstaller/Ruby1.8.7/lib/ruby/1.8/webrick/server.rb:162:in `start_thread'
  C:/RailsInstaller/Ruby1.8.7/lib/ruby/1.8/webrick/server.rb:95:in `start'
  C:/RailsInstaller/Ruby1.8.7/lib/ruby/1.8/webrick/server.rb:92:in `each'
  C:/RailsInstaller/Ruby1.8.7/lib/ruby/1.8/webrick/server.rb:92:in `start'
  C:/RailsInstaller/Ruby1.8.7/lib/ruby/1.8/webrick/server.rb:23:in `start'
  C:/RailsInstaller/Ruby1.8.7/lib/ruby/1.8/webrick/server.rb:82:in `start'
  rack (1.4.1) lib/rack/handler/webrick.rb:13:in `run'
  rack (1.4.1) lib/rack/server.rb:265:in `start'
  railties (3.2.1) lib/rails/commands/server.rb:70:in `start'
  railties (3.2.1) lib/rails/commands.rb:55
  railties (3.2.1) lib/rails/commands.rb:50:in `tap'
  railties (3.2.1) lib/rails/commands.rb:50
  script/rails:6:in `require'
  script/rails:6
  </code></pre>
  
  <p>SessionController : </p>
  
  <pre><code>    class SessionsController &lt; ApplicationController
        def create
          auth = request.env["omniauth.auth"]
          puts "printing"
          puts  auth
          session[:rtoken] = params[:token]
          session[:rsecret] = params[:secret]
          client = LinkedIn::Client.new("cus7tde3g4pe", "jKf6ZYgf8JhMoIJ4")
          if session[:atoken].nil?
            pin = params[:oauth_verifier]
            atoken, asecret = client.authorize_from_request(session[:rtoken], session[:rsecret], pin)
            session[:atoken] = atoken
            session[:asecret] = asecret
          else
            client.authorize_from_access(session[:atoken], session[:asecret])
          end
          @profile = client.profile
          @connections = client.connections
        end
        #user = User.find_by_provider_and_uid(auth["provider"], auth["uid"]) || User.create_with_omniauth(auth)
        session[:user_id] = profile.name
        redirect_to root_url, :notice =&gt; "Signed in!"
        #end
  
        def destroy
          session[:user_id] = nil
          redirect_to root_url, :notice =&gt; "Signed out!"
        end
      end
  
  Full Trace : 
  
  C:/linkedin/lovelinkedin/app/controllers/sessions_controller.rb:21: undefined local variable or method `session' for Ses
  sionsController:Class (NameError)
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:2
  51:in `require'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:2
  51:in `require'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:2
  36:in `load_dependency'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:2
  51:in `require'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:3
  59:in `require_or_load'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:3
  13:in `depend_on'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:2
  25:in `require_dependency'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/engine.rb:439:in `eager_load!'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/engine.rb:438:in `each'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/engine.rb:438:in `eager_load!'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/engine.rb:436:in `each'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/engine.rb:436:in `eager_load!'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/application/finisher.rb:53
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/initializable.rb:30:in `instanc
  e_exec'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/initializable.rb:30:in `run'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/initializable.rb:55:in `run_ini
  tializers'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/initializable.rb:54:in `each'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/initializable.rb:54:in `run_ini
  tializers'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/application.rb:136:in `initiali
  ze!'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/railtie/configurable.rb:30:in `
  send'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/railtie/configurable.rb:30:in `
  method_missing'
          from C:/linkedin/lovelinkedin/config/environment.rb:5
          from ./test/test_helper.rb:2:in `require'
          from ./test/test_helper.rb:2
          from C:/linkedin/lovelinkedin/test/unit/helpers/linkedin_helper_test.rb:1:in `require'
          from C:/linkedin/lovelinkedin/test/unit/helpers/linkedin_helper_test.rb:1
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/rake_test_loader.rb:15:in `require
  '
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/rake_test_loader.rb:15
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/rake_test_loader.rb:4:in `select'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/rake_test_loader.rb:4
  C:/linkedin/lovelinkedin/app/controllers/sessions_controller.rb:21: undefined local variable or method `session' for Ses
  sionsController:Class (NameError)
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:2
  51:in `require'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:2
  51:in `require'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:2
  36:in `load_dependency'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:2
  51:in `require'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:3
  59:in `require_or_load'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:3
  13:in `depend_on'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:2
  25:in `require_dependency'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/engine.rb:439:in `eager_load!'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/engine.rb:438:in `each'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/engine.rb:438:in `eager_load!'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/engine.rb:436:in `each'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/engine.rb:436:in `eager_load!'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/application/finisher.rb:53
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/initializable.rb:30:in `instanc
  e_exec'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/initializable.rb:30:in `run'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/initializable.rb:55:in `run_ini
  tializers'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/initializable.rb:54:in `each'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/initializable.rb:54:in `run_ini
  tializers'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/application.rb:136:in `initiali
  ze!'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/railtie/configurable.rb:30:in `
  send'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/railties-3.2.1/lib/rails/railtie/configurable.rb:30:in `
  method_missing'
          from C:/linkedin/lovelinkedin/config/environment.rb:5
          from ./test/test_helper.rb:2:in `require'
          from ./test/test_helper.rb:2
          from C:/linkedin/lovelinkedin/test/functional/linkedin_controller_test.rb:1:in `require'
          from C:/linkedin/lovelinkedin/test/functional/linkedin_controller_test.rb:1
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/rake_test_loader.rb:15:in `require
  '
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/rake_test_loader.rb:15
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/rake_test_loader.rb:4:in `select'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/rake_test_loader.rb:4
  </code></pre>
  
  <p>Please help me to solve this as i am new guy to ror.</p>