feat(gradebook): external assessment foundation (model, read serialization, inline grade entry)

Foundation layer for external assessments: data model + migrations, gradebook read serialization, and inline grade entry (update_grade). Management UI (panel, add/edit/delete), weight integration, and CSV import are introduced in later PRs of the stack.

Author: LWS49

app/controllers/course/external_assessments_controller.rb

@@ -0,0 +1,43 @@
+# frozen_string_literal: true
+class Course::ExternalAssessmentsController < Course::ComponentController
+  before_action :load_external_assessment, only: [:grades]
+
+  def grades
+    authorize! :grade, @external_assessment
+    # The gradebook keys students by user_id (see index/update_grade jbuilders), so the
+    # `studentId` param is a user_id, not a course_user PK.
+    course_user = current_course.course_users.find_by!(user_id: grade_params[:studentId])
+    @grade = @external_assessment.external_assessment_grades.
+             find_or_initialize_by(course_user: course_user)
+    @grade.grade = normalized_grade(grade_params[:grade])
+    @grade.save!
+    render 'update_grade'
+  rescue ActiveRecord::RecordNotUnique
+    retry
+  rescue ActiveRecord::RecordNotFound
+    head :not_found
+  rescue ActiveRecord::RecordInvalid => e
+    render json: { errors: { base: e.message } }, status: :unprocessable_entity
+  end
+
+  private
+
+  def component
+    current_component_host[:course_gradebook_component]
+  end
+
+  def load_external_assessment
+    @external_assessment = Course::ExternalAssessment.for_course(current_course).find(params[:id])
+  rescue ActiveRecord::RecordNotFound
+    head :not_found
+  end
+
+  def grade_params
+    params.permit(:studentId, :grade)
+  end
+
+  # Blank cell clears the grade to null (ungraded), never zero (decision #7).
+  def normalized_grade(value)
+    value.blank? ? nil : value
+  end
+end

app/models/course.rb

@@ -55,6 +55,8 @@ class Course < ApplicationRecord
   has_many :assessments, through: :assessment_categories
   has_many :gradebook_contributions, class_name: 'Course::Gradebook::Contribution',
                                      dependent: :destroy, inverse_of: :course
+  has_many :external_assessments, class_name: 'Course::ExternalAssessment',
+                                  inverse_of: :course, dependent: :destroy
   has_many :assessment_skills, class_name: 'Course::Assessment::Skill',
                                dependent: :destroy
   has_many :assessment_skill_branches, class_name: 'Course::Assessment::SkillBranch',

app/models/course/external_assessment.rb

@@ -0,0 +1,49 @@
+# frozen_string_literal: true
+# A gradebook component graded outside Coursemology (e.g. a midterm or final).
+# It is a first-class gradebook contributor, NOT a Course::Assessment: it never
+# touches attempts, EXP, statistics, todos, or the lesson plan. Its weight lives on
+# its course_gradebook_contributions row; its display grouping is synthesised by the
+# gradebook serializer (no real tab/category exists).
+class Course::ExternalAssessment < ApplicationRecord
+  # Sentinel id for the serializer's synthetic "External Assessments" category.
+  # Native categories are positive; externals and their synthetic grouping are negative.
+  SYNTHETIC_CATEGORY_ID = -1
+  SYNTHETIC_CATEGORY_TITLE = 'External Assessments'
+
+  validates :title, length: { maximum: 255 }, presence: true
+  validates :title, uniqueness: { scope: :course_id }
+  validates :maximum_grade, presence: true
+  validates :maximum_grade, numericality: { greater_than_or_equal_to: 0 }, allow_nil: true
+  validates :creator, presence: true
+  validates :updater, presence: true
+
+  belongs_to :course, inverse_of: :external_assessments
+  has_one :gradebook_contribution, class_name: 'Course::Gradebook::Contribution',
+                                   inverse_of: :external_assessment, dependent: :destroy
+  has_many :external_assessment_grades, class_name: 'Course::ExternalAssessmentGrade',
+                                        inverse_of: :external_assessment, dependent: :destroy
+
+  scope :for_course, ->(course) { where(course_id: course.id) }
+
+  # The negative serialized id used by the synthetic tab AND the leaf assessment.
+  def synthetic_tab_id
+    -id
+  end
+
+  # Creates an external assessment and its gradebook contribution in one transaction.
+  # Raises ActiveRecord::RecordInvalid on a duplicate title within the course.
+  # rubocop:disable Metrics/ParameterLists -- factory mirrors the model's columns; named kwargs are clearer than a struct
+  def self.create_for_course!(course:, title:, maximum_grade:, weight: 0,
+                              floor_at_zero: true, cap_at_maximum: true)
+    transaction do
+      external = course.external_assessments.create!(
+        title: title, maximum_grade: maximum_grade,
+        floor_at_zero: floor_at_zero, cap_at_maximum: cap_at_maximum
+      )
+      Course::Gradebook::Contribution.create!(course: course, external_assessment: external,
+                                              weight: weight, weight_mode: 'equal', keep_highest: 0)
+      external
+    end
+  end
+  # rubocop:enable Metrics/ParameterLists
+end

app/models/course/external_assessment_grade.rb

@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+# One external grade for a (external assessment, course_user). The binding key is
+# course_user_id (the authoritative link to the person); imported_identifier is a
+# non-authoritative snapshot of the email/Student ID used at import (audit + upsert
+# mismatch detection), null for grades typed/edited inline.
+class Course::ExternalAssessmentGrade < ApplicationRecord
+  validates :course_user, presence: true
+  validates :grade, numericality: true, allow_nil: true
+  validates :course_user_id, uniqueness: { scope: :external_assessment_id }
+  validates :creator, presence: true
+  validates :updater, presence: true
+
+  belongs_to :external_assessment, class_name: 'Course::ExternalAssessment',
+                                   inverse_of: :external_assessment_grades
+  belongs_to :course_user, inverse_of: :external_assessment_grades
+end

app/models/course/gradebook/contribution.rb

@@ -8,13 +8,16 @@ class Course::Gradebook::Contribution < ApplicationRecord
   belongs_to :course, inverse_of: :gradebook_contributions
   belongs_to :tab, class_name: 'Course::Assessment::Tab',
                    inverse_of: :gradebook_contribution, optional: true
+  belongs_to :external_assessment, class_name: 'Course::ExternalAssessment',
+                                   inverse_of: :gradebook_contribution, optional: true
 
   validates :creator, presence: true
   validates :updater, presence: true
   validates :weight, numericality: { greater_than_or_equal_to: 0, less_than_or_equal_to: 100 }
   validates :weight_mode, presence: true
   validates :keep_highest, numericality: { only_integer: true, greater_than_or_equal_to: 0 }
-  validates :tab_id, uniqueness: true
+  validates :tab_id, uniqueness: { allow_nil: true }
+  validates :external_assessment_id, uniqueness: { allow_nil: true }
   validate :exactly_one_contributor
   validate :course_matches_contributor
   # Bulk-upserts tab contributions and their per-assessment contributions for a course.
@@ -27,13 +30,22 @@ class Course::Gradebook::Contribution < ApplicationRecord
   # @param updates [Array<Hash>] each { tab_id:, weight:, weight_mode:, keep_highest:,
   #   excluded_assessment_ids: [Integer], assessment_weights: [{ assessment_id:, weight: }] }
   def self.bulk_update(course:, updates:)
+    external_updates, tab_updates = updates.partition { |e| e[:tab_id].to_i < 0 }
+
     course_tab_ids = course.assessment_tabs.pluck(:id).to_set
-    updates.each { |e| raise ActiveRecord::RecordNotFound unless course_tab_ids.include?(e[:tab_id]) }
+    tab_updates.each { |e| raise ActiveRecord::RecordNotFound unless course_tab_ids.include?(e[:tab_id]) }
+
+    external_ids = external_updates.map { |e| -e[:tab_id] }
+    externals_by_id = course.external_assessments.where(id: external_ids).index_by(&:id)
+    external_updates.each { |e| raise ActiveRecord::RecordNotFound unless externals_by_id.key?(-e[:tab_id]) }
 
-    tabs_by_id = Course::Assessment::Tab.where(id: updates.map { |e| e[:tab_id] }).
+    tabs_by_id = Course::Assessment::Tab.where(id: tab_updates.map { |e| e[:tab_id] }).
                  includes(:assessments).index_by(&:id)
 
-    transaction { updates.each { |entry| apply_entry(course, tabs_by_id, entry) } }
+    transaction do
+      tab_updates.each { |entry| apply_entry(course, tabs_by_id, entry) }
+      external_updates.each { |entry| apply_external_entry(course, externals_by_id[-entry[:tab_id]], entry) }
+    end
   end
 
   # @api private
@@ -58,6 +70,16 @@ def self.apply_entry(course, tabs_by_id, entry)
   end
   private_class_method :apply_entry
 
+  # @api private
+  def self.apply_external_entry(course, external, entry)
+    contribution = find_or_initialize_by(external_assessment_id: external.id)
+    contribution.tab = nil
+    contribution.course = course
+    contribution.assign_attributes(weight: entry[:weight], weight_mode: 'equal', keep_highest: 0)
+    contribution.save!
+  end
+  private_class_method :apply_external_entry
+
   # @api private
   def self.assessment_contribution_for(assessment)
     Course::Gradebook::AssessmentContribution.find_or_initialize_by(assessment_id: assessment.id)
@@ -117,15 +139,19 @@ def self.validate_custom_assessment_weights_sum!(tab, entry, included_sum, inclu
 
   private
 
-  # Until the external-alignment design adds `external_assessment_id`, the only
-  # contributor is the tab, so "exactly one" reduces to "tab present".
   def exactly_one_contributor
-    errors.add(:tab, :blank) if tab_id.blank?
+    return if [tab_id, external_assessment_id].compact.size == 1
+
+    errors.add(:base, :exactly_one_contributor)
   end
 
   def course_matches_contributor
-    return if tab.nil? || course.nil?
+    return if course.nil?
 
-    errors.add(:course, :invalid) if tab.category.course_id != course_id
+    contributor_course_id =
+      if tab then tab.category.course_id
+      elsif external_assessment then external_assessment.course_id
+      end
+    errors.add(:course, :invalid) if contributor_course_id && contributor_course_id != course_id
   end
 end

app/models/course_user.rb

@@ -50,6 +50,8 @@ class CourseUser < ApplicationRecord
                          inverse_of: :course_user, dependent: :destroy
   has_many :groups, through: :group_users, class_name: 'Course::Group', source: :group
   has_many :personal_times, class_name: 'Course::PersonalTime', inverse_of: :course_user, dependent: :destroy
+  has_many :external_assessment_grades, class_name: 'Course::ExternalAssessmentGrade',
+                                        inverse_of: :course_user, dependent: :destroy
   belongs_to :reference_timeline, class_name: 'Course::ReferenceTimeline', inverse_of: :course_users, optional: true
 
   default_scope { where(deleted_at: nil) }

app/views/course/external_assessments/update_grade.json.jbuilder

@@ -0,0 +1,4 @@
+# frozen_string_literal: true
+json.studentId @grade.course_user.user_id
+json.assessmentId(-@grade.external_assessment_id)
+json.grade @grade.grade&.to_f

app/views/course/gradebook/index.json.jbuilder

@@ -2,31 +2,71 @@
 json.weightedViewEnabled @weighted_view_enabled
 json.canManageWeights can?(:manage_gradebook_weights, current_course)
 
-json.categories @categories do |cat|
-  json.id cat.id
-  json.title cat.title
+json.categories do
+  json.array!(@categories) do |cat|
+    json.id cat.id
+    json.title cat.title
+  end
+  if @external_assessments.any?
+    json.child! do
+      json.id Course::ExternalAssessment::SYNTHETIC_CATEGORY_ID
+      json.title Course::ExternalAssessment::SYNTHETIC_CATEGORY_TITLE
+    end
+  end
 end
 
-json.tabs @tabs do |tab|
-  json.id tab.id
-  json.title tab.title
-  json.categoryId tab.category_id
-  if @weighted_view_enabled
-    contribution = @tab_contributions[tab.id]
-    json.gradebookWeight (contribution&.weight || 0).to_f
-    json.weightMode(contribution&.weight_mode || 'equal')
+json.tabs do
+  json.array!(@tabs) do |tab|
+    json.id tab.id
+    json.title tab.title
+    json.categoryId tab.category_id
+    if @weighted_view_enabled
+      contribution = @tab_contributions[tab.id]
+      json.gradebookWeight (contribution&.weight || 0).to_f
+      json.weightMode(contribution&.weight_mode || 'equal')
+    end
+  end
+  @external_assessments.each do |external|
+    json.child! do
+      json.id external.synthetic_tab_id
+      json.title external.title
+      json.categoryId Course::ExternalAssessment::SYNTHETIC_CATEGORY_ID
+      if @weighted_view_enabled
+        contribution = @external_contributions[external.id]
+        json.gradebookWeight (contribution&.weight || 0).to_f
+        json.weightMode 'equal'
+      end
+    end
   end
 end
 
-json.assessments @published_assessments do |assessment|
-  json.id assessment.id
-  json.title assessment.title
-  json.tabId assessment.tab_id
-  json.maxGrade @assessment_max_grades[assessment.id] || 0
-  if @weighted_view_enabled
-    contribution = @assessment_contributions[assessment.id]
-    json.gradebookWeight contribution&.weight&.to_f
-    json.gradebookExcluded(contribution&.excluded || false)
+json.assessments do
+  json.array!(@published_assessments) do |assessment|
+    json.id assessment.id
+    json.title assessment.title
+    json.tabId assessment.tab_id
+    json.maxGrade @assessment_max_grades[assessment.id] || 0
+    if @weighted_view_enabled
+      contribution = @assessment_contributions[assessment.id]
+      json.gradebookWeight contribution&.weight&.to_f
+      json.gradebookExcluded(contribution&.excluded || false)
+    end
+  end
+  @external_assessments.each do |external|
+    json.child! do
+      json.id(-external.id)
+      json.title external.title
+      json.tabId external.synthetic_tab_id
+      json.maxGrade external.maximum_grade.to_f
+      json.external true
+      json.floorAtZero external.floor_at_zero
+      json.capAtMaximum external.cap_at_maximum
+      if @weighted_view_enabled
+        contribution = @external_contributions[external.id]
+        json.gradebookWeight contribution&.weight&.to_f
+        json.gradebookExcluded false
+      end
+    end
   end
 end
 
@@ -39,11 +79,21 @@ json.students @students do |course_user|
   json.totalXp course_user.experience_points
 end
 
-json.submissions @submissions do |sub|
-  json.submissionId sub.submission_id
-  json.studentId sub.student_id
-  json.assessmentId sub.assessment_id
-  json.grade sub.grade&.to_f
+json.submissions do
+  json.array!(@submissions) do |sub|
+    json.submissionId sub.submission_id
+    json.studentId sub.student_id
+    json.assessmentId sub.assessment_id
+    json.grade sub.grade&.to_f
+  end
+  @external_grades.each do |grade|
+    json.child! do
+      json.studentId grade.course_user.user_id
+      json.assessmentId(-grade.external_assessment_id)
+      json.grade grade.grade&.to_f
+    end
+  end
 end
 
 json.gamificationEnabled current_course.gamified?
+json.userId current_user&.id

client/app/api/course/Gradebook.ts

@@ -1,4 +1,8 @@
-import { GradebookData, UpdateWeightsPayload } from 'types/course/gradebook';
+import {
+  ExternalGradePayload,
+  GradebookData,
+  UpdateWeightsPayload,
+} from 'types/course/gradebook';
 
 import { APIResponse } from 'api/types';
 
@@ -18,4 +22,14 @@ export default class GradebookAPI extends BaseCourseAPI {
   ): APIResponse<UpdateWeightsPayload> {
     return this.client.patch(`${this.#urlPrefix}/weights`, payload);
   }
+
+  setExternalGrade(
+    id: number,
+    payload: { studentId: number; grade: number | null },
+  ): APIResponse<ExternalGradePayload> {
+    return this.client.put(
+      `${this.#urlPrefix}/external_assessments/${id}/grades`,
+      payload,
+    );
+  }
 }

client/app/bundles/course/gradebook/__tests__/buildAssessmentColumnIds.test.ts

@@ -0,0 +1,31 @@
+import {
+  buildAssessmentColumnId,
+  parseAssessmentColumnId,
+} from '../components/buildAssessmentColumnIds';
+
+describe('assessment column ids', () => {
+  it('round-trips a positive (regular) assessment id', () => {
+    expect(parseAssessmentColumnId(buildAssessmentColumnId(100))).toBe(100);
+  });
+
+  it('round-trips a negative (external) assessment id', () => {
+    expect(parseAssessmentColumnId(buildAssessmentColumnId(-5))).toBe(-5);
+  });
+
+  it('returns null for a non-assessment column id', () => {
+    expect(parseAssessmentColumnId('name')).toBeNull();
+    expect(parseAssessmentColumnId('totalXp')).toBeNull();
+  });
+
+  it('round-trips a zero id (falsy but valid)', () => {
+    expect(parseAssessmentColumnId(buildAssessmentColumnId(0))).toBe(0);
+  });
+
+  it('returns null for a malformed or unanchored asn- column id', () => {
+    expect(parseAssessmentColumnId('asn-')).toBeNull();
+    expect(parseAssessmentColumnId('asn-abc')).toBeNull();
+    expect(parseAssessmentColumnId('asn-1.5')).toBeNull();
+    expect(parseAssessmentColumnId('asn-12x')).toBeNull();
+    expect(parseAssessmentColumnId('xasn-12')).toBeNull();
+  });
+});