Refactor LTI parameters and add study group

* This change also requires that submissions in our test need to have a valid study group.

app/controllers/concerns/lti.rb

@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-require 'oauth/request_proxy/rack_request'
+require 'oauth/request_proxy/action_controller_request'
 
 module Lti
   extend ActiveSupport::Concern
@@ -21,7 +21,7 @@ module Lti
 
   # exercise_id.nil? ==> the user has logged out. All session data is to be destroyed
   # exercise_id.exists? ==> the user has submitted the results of an exercise to the consumer.
-  # Only the lti_parameters are deleted.
+  # Only the assignment of the programming group is deleted.
   def clear_lti_session_data(exercise_id = nil)
     if exercise_id.nil?
       session.delete(:external_user_id)
@@ -148,10 +148,7 @@ module Lti
 
   def send_score_for(submission, user)
     if user.consumer
-      lti_parameter = LtiParameter.where(consumers_id: user.consumer.id,
-        external_users_id: user.id,
-        exercises_id: submission.exercise_id).last
-
+      lti_parameter = user.lti_parameters.find_by(exercise: submission.exercise, study_group: submission.study_group)
       provider = build_tool_provider(consumer: user.consumer, parameters: lti_parameter&.lti_parameters)
     end
 
@@ -237,14 +234,13 @@ module Lti
 
   private :set_embedding_options
 
-  def store_lti_session_data(options = {})
-    lti_parameters = LtiParameter.find_or_create_by(consumers_id: options[:consumer].id,
-      external_users_id: current_user.id,
-      exercises_id: @exercise.id)
+  def store_lti_session_data(parameters)
+    @lti_parameters = LtiParameter.find_or_initialize_by(external_user: current_user,
+      study_group_id: session[:study_group_id],
+      exercise: @exercise)
 
-    lti_parameters.lti_parameters = options[:parameters].slice(*SESSION_PARAMETERS).permit!.to_h
-    lti_parameters.save!
-    @lti_parameters = lti_parameters
+    @lti_parameters.lti_parameters = parameters.slice(*SESSION_PARAMETERS).permit!.to_h
+    @lti_parameters.save!
 
     session[:external_user_id] = current_user.id
   end

app/controllers/exercises_controller.rb

@@ -527,7 +527,7 @@ class ExercisesController < ApplicationController
     @submission = Submission.create(submission_params)
     @submission.calculate_score
 
-    if @submission.users.map {|user| user.external_user? && lti_outcome_service?(@submission.exercise_id, user.id) }.any?
+    if @submission.users.map {|user| lti_outcome_service?(@submission.exercise, user, @submission.study_group_id) }.any?
       transmit_lti_score
     else
       redirect_after_submit

app/controllers/programming_groups_controller.rb

@@ -13,7 +13,7 @@ class ProgrammingGroupsController < ApplicationController
     if existing_programming_group
       session[:pg_id] = existing_programming_group.id
       redirect_to(implement_exercise_path(@exercise),
-        notice: t("sessions.create_through_lti.session_#{lti_outcome_service?(@exercise.id, current_user.id) ? 'with' : 'without'}_outcome", consumer: @consumer))
+        notice: t("sessions.create_through_lti.session_#{lti_outcome_service?(@exercise, current_user) ? 'with' : 'without'}_outcome", consumer: @consumer))
     end
   end
 

app/controllers/remote_evaluation_controller.rb

@@ -35,7 +35,7 @@ class RemoteEvaluationController < ApplicationController
 
   def try_lti
     # TODO: Need to consider and support programming groups
-    if !@submission.user.nil? && lti_outcome_service?(@submission.exercise_id, @submission.user.id)
+    if !@submission.user.nil? && lti_outcome_service?(@submission.exercise, @submission.user, @submission.study_group_id)
       lti_responses = send_scores(@submission)
       process_lti_response(lti_responses.first)
     else

app/controllers/sessions_controller.rb

@@ -17,7 +17,7 @@ class SessionsController < ApplicationController
   end
 
   def create_through_lti
-    store_lti_session_data(consumer: @consumer, parameters: params)
+    store_lti_session_data(params)
     store_nonce(params[:oauth_nonce])
     if params[:custom_redirect_target]
       redirect_to(URI.parse(params[:custom_redirect_target].to_s).path)
@@ -25,7 +25,7 @@ class SessionsController < ApplicationController
       redirect_to(new_exercise_programming_group_path(@exercise))
     else
       redirect_to(implement_exercise_path(@exercise),
-        notice: t("sessions.create_through_lti.session_#{lti_outcome_service?(@exercise.id, current_user.id) ? 'with' : 'without'}_outcome",
+        notice: t("sessions.create_through_lti.session_#{lti_outcome_service?(@exercise, current_user) ? 'with' : 'without'}_outcome",
           consumer: @consumer))
     end
   end
@@ -44,7 +44,7 @@ class SessionsController < ApplicationController
   def destroy_through_lti
     @submission = Submission.find(params[:submission_id])
     authorize(@submission, :show?)
-    lti_parameter = LtiParameter.where(external_users_id: current_user.id, exercises_id: @submission.exercise_id).last
+    lti_parameter = current_user.lti_parameters.find_by(exercise: @submission.exercise, study_group_id: current_user.current_study_group_id)
     @url = consumer_return_url(build_tool_provider(consumer: current_user.consumer, parameters: lti_parameter&.lti_parameters))
 
     clear_lti_session_data(@submission.exercise_id)

app/helpers/lti_helper.rb

@@ -1,13 +1,17 @@
 # frozen_string_literal: true
 
-require 'oauth/request_proxy/action_controller_request' # Rails 5 changed `Rack::Request` to `ActionDispatch::Request`
-
 module LtiHelper
-  def lti_outcome_service?(exercise_id, external_user_id)
-    return false if external_user_id == ''
+  # Checks for support of the LTI outcome service for the given exercise and user.
+  # If the user passed is not the `current_user`, a study group id **must** be passed as well.
+  def lti_outcome_service?(exercise, user, study_group_id = user.current_study_group_id)
+    return false unless user.external_user?
 
-    lti_parameters = LtiParameter.where(external_users_id: external_user_id,
-      exercises_id: exercise_id).lis_outcome_service_url?.last
-    !lti_parameters.nil? && lti_parameters.present?
+    lis_outcome_service_parameters(exercise, user, study_group_id).present?
+  end
+
+  private
+
+  def lis_outcome_service_parameters(exercise, external_user, study_group_id)
+    external_user.lti_parameters.lis_outcome_service_url?.find_by(exercise:, study_group_id:)
   end
 end

app/models/external_user.rb

@@ -2,6 +2,7 @@
 
 class ExternalUser < User
   validates :external_id, presence: true
+  has_many :lti_parameters, dependent: :destroy
 
   def displayname
     name.presence || "User #{id}"

app/models/lti_parameter.rb

@@ -1,9 +1,12 @@
 # frozen_string_literal: true
 
 class LtiParameter < ApplicationRecord
-  belongs_to :consumer, foreign_key: 'consumers_id'
-  belongs_to :exercise, foreign_key: 'exercises_id'
-  belongs_to :external_user, foreign_key: 'external_users_id'
+  belongs_to :exercise
+  belongs_to :external_user
+  belongs_to :study_group, optional: true
+  delegate :consumer, to: :external_user
+
+  validates :external_user_id, uniqueness: {scope: %i[study_group_id exercise_id]}
 
   scope :lis_outcome_service_url?, lambda {
     where("lti_parameters.lti_parameters ? 'lis_outcome_service_url'")

app/models/study_group.rb

@@ -8,6 +8,7 @@ class StudyGroup < ApplicationRecord
   has_many :remote_evaluation_mappings, dependent: :nullify
   has_many :subscriptions, dependent: :nullify
   has_many :authentication_tokens, dependent: :nullify
+  has_many :lti_parameters, dependent: :delete_all
   belongs_to :consumer
 
   def users

app/views/exercises/_editor.html.slim

@@ -1,6 +1,4 @@
 - external_user_external_id = current_user.respond_to?(:external_id) ? current_user.external_id : ''
-- external_user_id = current_user.respond_to?(:external_id) ? current_user.id : ''
-- consumer_id = current_user.respond_to?(:external_id) ? current_user.consumer_id : ''
 - show_break_interventions = @show_break_interventions || "false"
 - show_rfc_interventions = @show_rfc_interventions || "false"
 - show_tips_interventions = @show_tips_interventions || "false"
@@ -53,7 +51,7 @@
           = t('exercises.editor.start_over_active_file')
 
   - unless @embed_options[:disable_run] && @embed_options[:disable_score]
-    div id='output_sidebar' class='output-col-collapsed' = render('exercises/editor_output', external_user_id: external_user_id, consumer_id: consumer_id )
+    div id='output_sidebar' class='output-col-collapsed' = render('exercises/editor_output')
 
 
 = render('shared/modal', id: 'comment-modal', title: t('exercises.implement.comment.request'), template: 'exercises/_request_comment_dialogcontent') unless @embed_options[:disable_rfc]

app/views/exercises/_editor_output.html.slim

@@ -60,7 +60,7 @@ div.d-grid id='output_sidebar_uncollapsed' class='d-none col-sm-12 enforce-botto
           .progress-bar role='progressbar'
 
       br
-      - if lti_outcome_service?(@exercise.id, external_user_id)
+      - if lti_outcome_service?(@exercise, current_user)
         p.text-center = render('editor_button', classes: 'btn-lg btn-success d-none', data: {:'data-url' => submit_exercise_path(@exercise)}, icon: 'fa-solid fa-paper-plane', id: 'submit', label: t('exercises.editor.submit'))
         - if @exercise.submission_deadline.present? || @exercise.late_submission_deadline.present?
           #deadline data-submission-deadline=@exercise.submission_deadline&.rfc2822 data-late-submission-deadline=@exercise.late_submission_deadline&.rfc2822