Update Lecture-Recording relationship and add Lecture cancellation status

The commit introduces notable changes to the Lecture-Recording model relationship in our application and adds a new cancellation status to Lecture model.

Models Lecture and Recording previously had a belongs_to :recording and belongs_to :lecture relationship respectively. However, this setup was not reflecting the correct relationship between these two entities in the actual educational setup where a lecture can have a recording but a recording is always of a lecture. Thus, the relationship has been revised to has_one :recording in Lecture and belongs_to :lecture in Recording models.

Also, added the ability to mark a lecture as "cancelled". This addresses the requirement of representing real-world scenarios where lectures are sometimes cancelled. This cancellation status is then reflected in the Attendance Tracker view and is also handled in the ScrapePanoptoJob.

Additionally, new changes are reflected in the application's schema, migration files, admin dashboard, and stylesheets (for displaying cancelled lectures).

app/assets/stylesheets/application.css

@@ -14,3 +14,11 @@
  *= require _font-awesome
  *= require_self
  */
+
+.lecture-future {
+    background: repeating-linear-gradient(45deg, #f3f4f6, #f3f4f6 10px, white 10px, white 20px);
+}
+
+.lecture-cancelled {
+    background: repeating-linear-gradient(45deg, rgb(254 226 226/var(--tw-bg-opacity)), rgb(254 226 226/var(--tw-bg-opacity)) 10px, white 10px, white 20px);
+}

app/dashboards/lecture_dashboard.rb

@@ -12,9 +12,10 @@ class LectureDashboard < Administrate::BaseDashboard
     attendance: Field::HasOne,
     course: Field::BelongsTo,
     event_uuid: Field::String,
-    recording: Field::BelongsTo,
+    recording: Field::HasOne,
     start_time: Field::DateTime,
     title: Field::String,
+    cancelled: Field::Boolean,
     created_at: Field::DateTime,
     updated_at: Field::DateTime,
   }.freeze
@@ -27,6 +28,7 @@ class LectureDashboard < Administrate::BaseDashboard
   COLLECTION_ATTRIBUTES = %i[
     title
     course
+    cancelled
     start_time
     recording
   ].freeze
@@ -37,6 +39,7 @@ class LectureDashboard < Administrate::BaseDashboard
     id
     attendance
     course
+    cancelled
     event_uuid
     recording
     start_time
@@ -51,6 +54,7 @@ class LectureDashboard < Administrate::BaseDashboard
   FORM_ATTRIBUTES = %i[
     attendance
     course
+    cancelled
     event_uuid
     recording
     start_time

app/dashboards/recording_dashboard.rb

@@ -10,6 +10,7 @@ class RecordingDashboard < Administrate::BaseDashboard
   ATTRIBUTE_TYPES = {
     id: Field::Number,
     course: Field::BelongsTo,
+    lecture: Field::BelongsTo,
     recording_uuid: Field::String,
     start_time: Field::DateTime,
     title: Field::String,

app/jobs/scrape_panopto_job.rb

@@ -36,11 +36,10 @@ class ScrapePanoptoJob < ApplicationJob
           lecture.update!(recording_id: new_recording.id)
         else
           # Else create a new lecture
-          Lecture.create!(
+          lecture = Lecture.create!(
             title: new_recording.nice_title,
             start_time: new_recording.start_time,
             course_id: new_recording.course_id,
-            recording_id: new_recording.id
           )
         end
       end

app/models/lecture.rb

@@ -1,7 +1,7 @@
 class Lecture < ApplicationRecord
   belongs_to :course
   has_one :attendance
-  belongs_to :recording, optional: true
+  has_one :recording
 
   def week_number
     ((start_time.beginning_of_week - course.semester_start_date.to_time) / 1.week).floor + 1

app/models/recording.rb

@@ -1,6 +1,7 @@
 # This is a Foreign Object Reference Table, keyed to the external data source by #recording_uuid
 class Recording < ApplicationRecord
   belongs_to :course
+  belongs_to :lecture, optional: true
 
   def recording_url
     return nil if recording_uuid.nil?
@@ -17,4 +18,12 @@ class Recording < ApplicationRecord
 
     title
   end
+
+  def create_lecture!(fixup_time: false)
+    Lecture.create!(
+      title: nice_title,
+      course: course,
+      recording: self
+    )
+  end
 end

app/views/attendance_tracker/index.html.erb

@@ -25,8 +25,10 @@
                 </tr>
 
                 <% lectures.each do |lecture| %>
-                  <% style = if lecture.start_time.future? then 'background: repeating-linear-gradient(45deg, #f3f4f6, #f3f4f6 10px, white 10px, white 20px);' else '' end %>
-                  <tr style="<%= style %>">
+                  <tr class="<%= class_names({
+                                               'lecture-future': lecture.start_time.future?,
+                                               'lecture-cancelled': lecture.cancelled,
+                                             }) %>">
                     <td class="whitespace-nowrap py-4 pl-4 pr-3 text-sm font-medium text-gray-900 sm:pl-6">
                       <%= lecture.title %>
                     </td>
@@ -34,7 +36,7 @@
                       <%= lecture.start_time.to_fs(:dmy) %>
                     </td>
 
-                    <% if lecture.start_time.future? %>
+                    <% if lecture.start_time.future? || lecture.cancelled %>
                       <td class="whitespace-nowrap px-3 py-4 text-sm text-gray-500">
                       </td>
 

db/migrate/20231001191113_change_lecture_recording_ownership_relation.rb

@@ -0,0 +1,6 @@
+class ChangeLectureRecordingOwnershipRelation < ActiveRecord::Migration[7.0]
+  def change
+    remove_column :lectures, :recording_id
+    add_belongs_to :recordings, :lecture
+  end
+end

db/migrate/20231002083755_add_cancelled_status_to_lecture.rb

@@ -0,0 +1,5 @@
+class AddCancelledStatusToLecture < ActiveRecord::Migration[7.0]
+  def change
+    add_column :lectures, :cancelled, :boolean, default: false
+  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[7.0].define(version: 2023_10_01_183712) do
+ActiveRecord::Schema[7.0].define(version: 2023_10_02_083755) do
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
 
@@ -39,10 +39,9 @@ ActiveRecord::Schema[7.0].define(version: 2023_10_01_183712) do
     t.datetime "created_at", null: false
     t.datetime "updated_at", null: false
     t.bigint "course_id"
-    t.bigint "recording_id"
     t.string "event_uuid"
+    t.boolean "cancelled", default: false
     t.index ["course_id"], name: "index_lectures_on_course_id"
-    t.index ["recording_id"], name: "index_lectures_on_recording_id"
   end
 
   create_table "recordings", force: :cascade do |t|
@@ -52,7 +51,9 @@ ActiveRecord::Schema[7.0].define(version: 2023_10_01_183712) do
     t.bigint "course_id", null: false
     t.datetime "created_at", null: false
     t.datetime "updated_at", null: false
+    t.bigint "lecture_id"
     t.index ["course_id"], name: "index_recordings_on_course_id"
+    t.index ["lecture_id"], name: "index_recordings_on_lecture_id"
     t.index ["recording_uuid"], name: "index_recordings_on_recording_uuid", unique: true
   end