Add additional logging for Sentry

app/controllers/concerns/lti.rb

@@ -105,11 +105,12 @@ module Lti
 
   def require_valid_exercise_token
     proxy_exercise = ProxyExercise.find_by(token: params[:custom_token])
-    @exercise = unless proxy_exercise.nil?
+    @exercise = if proxy_exercise.nil?
-                  proxy_exercise.get_matching_exercise(@current_user)
-                else
                   Exercise.find_by(token: params[:custom_token])
+                else
+                  proxy_exercise.get_matching_exercise(@current_user)
                 end
+    session[:lti_exercise_id] = @exercise.id
     refuse_lti_launch(message: t('sessions.oauth.invalid_exercise_token')) unless @exercise
   end
 

app/controllers/exercises_controller.rb

@@ -323,6 +323,7 @@ class ExercisesController < ApplicationController
   end
 
   def redirect_to_lti_return_path
+    begin
       lti_parameter = LtiParameter.where(consumers_id: session[:consumer_id],
                                          external_users_id: @submission.user_id,
                                          exercises_id: @submission.exercise_id).first
@@ -335,6 +336,18 @@ class ExercisesController < ApplicationController
         format.html { redirect_to(path) }
         format.json { render(json: {redirect: path}) }
       end
+    rescue StandardError
+      Raven.extra_context(
+        consumers_id: session[:consumer_id],
+        external_users_id: @submission.user_id,
+        exercises_id: @submission.exercise_id,
+        session: session,
+        submission: @submission,
+        params: params,
+        current_user: current_user,
+        lti_exercise_id: session[:lti_exercise_id]
+      )
+    end
   end
   private :redirect_to_lti_return_path