Move submission version logic to be handled by AUD

app/helpers/assessment_handin_core.rb

@@ -18,6 +18,7 @@ def validateHandin(size, content_type, filename)
     if size > @assessment.max_size * (2**20)
       return :file_too_large
     end
+
     # Check if mimetype is correct (if overwritten by assessment config)
     begin
       if @assessment.overwrites_method?(:checkMimeType) and 
@@ -42,6 +43,7 @@ def validateHandinForGroups
 
     submitter_aud = @assessment.aud_for(@cud.id)
     return :valid unless submitter_aud
+
     group = submitter_aud.group
     return :valid unless group
 
@@ -54,6 +56,7 @@ def validateHandinForGroups
 
       submission_count = aud.course_user_datum.submissions.where(assessment: @assessment).size
       next unless submission_count >= @assessment.max_submissions
+
       return :group_submission_limit_exceeded
     end
 

app/models/assessment_user_datum.rb

@@ -238,6 +238,20 @@ def global_cumulative_grace_days_used
     cumulative_grace_days_used
   end
 
+  # atomic way of updating version number
+  # (necessary in the case multiple submissions made concurrently)
+  def update_version_number
+    with_lock do
+      if version_number.nil?
+        self.version_number = 1
+      else
+        self.version_number += 1
+      end
+      save!
+    end
+    self.version_number
+  end
+
 protected
 
   def cumulative_grace_days_used

app/models/submission.rb

@@ -20,7 +20,6 @@ class Submission < ApplicationRecord
 
   validate :allowed?, on: :create
   validates_associated :assessment
-  validates :version, uniqueness: { scope: %i[course_user_datum_id assessment_id] }
   validate :user_and_assessment_in_same_course
   validates :notes, length: { maximum: 255 }
 
@@ -271,14 +270,7 @@ def user_and_assessment_in_same_course
 
   def set_version
     self.submitted_by_id = course_user_datum_id unless submitted_by_id
-    begin
-      if version != 0
-        self.version = 1 + assessment.submissions.where(course_user_datum:
-          course_user_datum).maximum(:version)
-      end
-    rescue TypeError
-      self.version = 1
-    end
+    self.version = aud.update_version_number
   end
 
   def problems_to_scores

db/migrate/20231208083728_add_version_number_to_assessment_user_data.rb

@@ -0,0 +1,16 @@
+class AddVersionNumberToAssessmentUserData < ActiveRecord::Migration[6.0]
+  def up
+    add_column :assessment_user_data, :version_number, :integer
+    AssessmentUserDatum.all.each do |aud|
+      max_submission_version = Submission.where(course_user_datum_id: aud.course_user_datum_id, assessment_id: aud.assessment_id).maximum(:version)
+      if max_submission_version.nil?
+        aud.update(version_number: 0)
+      else
+        aud.update(version_number: max_submission_version)
+      end
+    end
+  end
+  def down
+    remove_column :assessment_user_data, :version_number, :integer
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2023_09_24_163059) do
+ActiveRecord::Schema.define(version: 2023_12_08_083728) do
 
   create_table "annotations", force: :cascade do |t|
     t.integer "submission_id"
@@ -51,6 +51,7 @@
     t.string "repository", limit: 255
     t.integer "group_id"
     t.integer "membership_status", limit: 1, default: 0
+    t.integer "version_number"
     t.index ["assessment_id"], name: "index_assessment_user_data_on_assessment_id"
     t.index ["course_user_datum_id", "assessment_id"], name: "index_AUDs_on_CUD_id_and_assessment_id"
     t.index ["course_user_datum_id"], name: "index_assessment_user_data_on_course_user_datum_id"

spec/sets/submissions.rb

@@ -21,7 +21,8 @@ def create_submissions_for_student(asmt: @assessment, student: @students.first)
       # TODO: replace with factorybot
       # needed to bypass validations, but jank
       AssessmentUserDatum.create_modulo_callbacks(assessment_id: asmt.id,
-                                                  course_user_datum_id: student.id)
+                                                  course_user_datum_id: student.id,
+                                                  version_number: 0)
       aud = AssessmentUserDatum.find_by(assessment_id: asmt.id,
                                         course_user_datum_id: student.id)
       # students in this course are given nicknames to bypass