Allow to prohibit submissions to a task for selected users

src/tasks/admin.py

@@ -6,7 +6,7 @@
 from django.urls import reverse
 from django.utils.html import format_html
 
-from tasks.models import Task, MediaFile, HtmlInjector, DeadlineExtension
+from tasks.models import Task, MediaFile, HtmlInjector, SubmissionBlacklistEntry, DeadlineExtension
 from solutions.models import Solution, SolutionFile
 from attestation.admin import RatingAdminInline
 
@@ -25,6 +25,11 @@ class HtmlInjectorInline(admin.StackedInline):
     model = HtmlInjector
     extra = 0
 
+class SubmissionBlacklistInline(admin.TabularInline):
+    model = SubmissionBlacklistEntry
+    verbose_name_plural = "Submission Blacklist Entries"
+    extra = 0
+
 class DeadlineExtensionInline(admin.TabularInline):
     model = DeadlineExtension
     extra = 0
@@ -54,7 +59,7 @@ class TaskAdmin(admin.ModelAdmin):
     date_hierarchy = 'publication_date'
     save_on_top = True
 
-    inlines = [DeadlineExtensionInline] + [MediaInline] + [HtmlInjectorInline] + CheckerInline.__subclasses__() + [ RatingAdminInline]
+    inlines = [SubmissionBlacklistInline] + [DeadlineExtensionInline] + [MediaInline] + [HtmlInjectorInline] + CheckerInline.__subclasses__() + [ RatingAdminInline]
     actions = ['export_tasks', 'run_all_checkers', 'run_all_checkers_on_finals', 'run_all_checkers_on_latest_only_failed', 'check_unchecked_final_solutions', 'delete_attestations', 'unset_all_checker_finished', 'run_all_uploadtime_checkers_on_all']
 
     class Media:

src/tasks/migrations/0019_submissionblacklistentry.py

@@ -0,0 +1,23 @@
+# Generated by Django 5.1.2 on 2025-01-30 01:53
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('accounts', '0008_accept_disclaimer'),
+        ('tasks', '0018_task_custom_id'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='SubmissionBlacklistEntry',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('task', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to='tasks.task')),
+                ('user', models.ForeignKey(limit_choices_to={'groups__name': 'User'}, on_delete=django.db.models.deletion.CASCADE, to='accounts.user')),
+            ],
+        ),
+    ]

src/tasks/models.py

@@ -61,6 +61,8 @@ def expired(self):
 
     def expired_for_user(self, user):
         """returns whether the task has expired for a certain user"""
+        if SubmissionBlacklistEntry.objects.filter(task=self, user=user).exists():
+            return True
         for deadline_extension in DeadlineExtension.objects.filter(task=self, user=user):
             return deadline_extension.timestamp + get_settings().deadline_tolerance < datetime.now()
         return self.expired()
@@ -419,6 +421,11 @@ class HtmlInjector(models.Model):
     html_file = DeletingFileField(upload_to=get_htmlinjectorfile_storage_path, max_length=500)
 
 
+class SubmissionBlacklistEntry(models.Model):
+    task = models.ForeignKey(Task, on_delete=models.CASCADE)
+    user = models.ForeignKey(User, on_delete=models.CASCADE, limit_choices_to={"groups__name": "User"})
+
+
 class DeadlineExtension(models.Model):
     task = models.ForeignKey(Task, on_delete=models.CASCADE)
     user = models.ForeignKey(User, on_delete=models.CASCADE, limit_choices_to={"groups__name": "User"})