Quiz submission limit and Per Student Overrides

tin/apps/assignments/admin.py

@@ -6,6 +6,7 @@
 
 from .models import (
     Assignment,
+    AssignmentOverride,
     CooldownPeriod,
     FileAction,
     Folder,
@@ -140,3 +141,6 @@ def match(self, obj):
         elif obj.match_type == "C":
             return f"*{obj.match_value}*"
         return ""
+
+
+admin.site.register(AssignmentOverride)

tin/apps/assignments/forms.py

@@ -7,7 +7,7 @@
 from django.conf import settings
 
 from ..submissions.models import Submission
-from .models import Assignment, Folder, MossResult
+from .models import Assignment, AssignmentOverride, Folder, MossResult
 
 logger = getLogger(__name__)
 
@@ -30,6 +30,10 @@ def __init__(self, course, *args, **kwargs):
         # prevent description from getting too big
         self.fields["description"].widget.attrs.update({"id": "description"})
 
+        # these fields aren't required
+        for field in ("submission_cap", "submission_cap_after_due"):
+            self.fields[field].required = False
+
     def get_sections(self) -> Iterable[dict[str, str | tuple[str, ...] | bool]]:
         """This is used in templates to find which fields should be in a dropdown div."""
         for section in self.Meta.sections:
@@ -66,6 +70,9 @@ class Meta:
             "grader_timeout",
             "grader_has_network_access",
             "has_network_access",
+            "use_submission_cap",
+            "submission_cap",
+            "submission_cap_after_due",
             "submission_limit_count",
             "submission_limit_interval",
             "submission_limit_cooldown",
@@ -83,6 +90,7 @@ class Meta:
             "grader_timeout": "Grader timeout (seconds):",
             "grader_has_network_access": "Give the grader internet access?",
             "has_network_access": "Give submissions internet access?",
+            "use_submission_cap": "Cap submissions?",
             "submission_limit_count": "Rate limit count",
             "submission_limit_interval": "Rate limit interval (minutes)",
             "submission_limit_cooldown": "Rate limit cooldown period (minutes)",
@@ -136,6 +144,9 @@ class Meta:
                     "submission_limit_count",
                     "submission_limit_interval",
                     "submission_limit_cooldown",
+                    "use_submission_cap",
+                    "submission_cap",
+                    "submission_cap_after_due",
                 ),
                 "collapsed": True,
             },
@@ -150,6 +161,9 @@ class Meta:
             'internet access" below. If set, it increases the amount '
             "of time it takes to start up the grader (to about 1.5 "
             "seconds). This is not recommended unless necessary.",
+            "use_submission_cap": "This enables setting a limit on the number of submissions that can be made on assignments."
+            "It has no effect on quizzes",
+            "submission_cap": "The maximum number of submissions that can be made. It can be overridden on a per-student basis.",
             "submission_limit_count": "",
             "submission_limit_interval": "Tin sets rate limits on submissions. If a student tries "
             "to submit too many submissions in a given interval, "
@@ -241,3 +255,12 @@ class Meta:
             "name",
         ]
         help_texts = {"name": "Note: Folders are ordered alphabetically."}
+
+
+class AssignmentOverrideForm(forms.ModelForm):
+    class Meta:
+        model = AssignmentOverride
+        fields = [
+            "submission_cap",
+        ]
+        help_texts = {"submission_cap": "The maximum number of submissions that can be made."}

tin/apps/assignments/migrations/0033_assignment_submission_cap_and_more.py

@@ -0,0 +1,41 @@
+# Generated by Django 4.2.14 on 2024-09-02 00:46
+
+from django.conf import settings
+import django.core.validators
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+        ('assignments', '0032_assignment_quiz_description_and_more'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='assignment',
+            name='submission_cap',
+            field=models.PositiveSmallIntegerField(null=True, validators=[django.core.validators.MinValueValidator(1)]),
+        ),
+        migrations.AddField(
+            model_name='assignment',
+            name='submission_cap_after_due',
+            field=models.PositiveSmallIntegerField(null=True, validators=[django.core.validators.MinValueValidator(1)]),
+        ),
+        migrations.AddField(
+            model_name='assignment',
+            name='use_submission_cap',
+            field=models.BooleanField(default=False),
+        ),
+        migrations.CreateModel(
+            name='AssignmentOverride',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('submission_cap', models.PositiveSmallIntegerField(default=None, null=True)),
+                ('assignment', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='student_overrides', to='assignments.assignment')),
+                ('student', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to=settings.AUTH_USER_MODEL)),
+            ],
+        ),
+    ]

tin/apps/assignments/models.py

@@ -159,6 +159,7 @@ class Assignment(models.Model):
 
     has_network_access = models.BooleanField(default=False)
 
+    # WARNING: this is the rate limit
     submission_limit_count = models.PositiveIntegerField(
         default=90,
         validators=[MinValueValidator(10)],
@@ -172,6 +173,16 @@ class Assignment(models.Model):
         validators=[MinValueValidator(10)],
     )
 
+    use_submission_cap = models.BooleanField(default=False)
+    submission_cap = models.PositiveSmallIntegerField(
+        null=True,
+        validators=[MinValueValidator(1)],
+    )
+    submission_cap_after_due = models.PositiveSmallIntegerField(
+        null=True,
+        validators=[MinValueValidator(1)],
+    )
+
     last_action_output = models.CharField(max_length=16 * 1024, default="", null=False, blank=True)
 
     is_quiz = models.BooleanField(default=False)
@@ -192,6 +203,39 @@ def get_absolute_url(self):
     def __repr__(self):
         return self.name
 
+    def within_submission_limit(self, student) -> bool:
+        """Check if a student is within the submission limit for an assignment."""
+        # teachers should have infinite submissions
+        if not student.is_student or not self.use_submission_cap:
+            return True
+
+        # note that this doesn't care about killed/incomplete submissions
+        submission_count = self.submissions.filter(student=student).count()
+
+        cap = self.find_submission_cap(student)
+        return submission_count < cap
+
+    def find_submission_cap(self, student) -> float:
+        """Given a student, find the submission cap.
+
+        This takes into account student overrides, and due dates.
+        """
+        if student.is_superuser or student.is_teacher:
+            return float("inf")
+        data = self.find_student_override(student)
+        if data is not None:
+            return data.submission_cap
+        elif timezone.localtime() > self.due:
+            return self.submission_cap_after_due or float("inf")
+        return self.submission_cap or float("inf")
+
+    def find_student_override(self, student) -> AssignmentOverride | None:
+        """Find an :class:`.AssignmentOverride` for a student.
+
+        Returns ``None`` if no override exists.
+        """
+        return self.student_overrides.filter(student=student).first()
+
     def make_assignment_dir(self) -> None:
         """Creates the directory where the assignment grader scripts go."""
         assignment_path = os.path.join(settings.MEDIA_ROOT, f"assignment-{self.id}")
@@ -371,6 +415,26 @@ def quiz_issues_for_student(self, student) -> bool:
         )
 
 
+class AssignmentOverride(models.Model):
+    """A collection of per-student overrides for each :class:`.Assignment`."""
+
+    assignment = models.ForeignKey(
+        Assignment,
+        on_delete=models.CASCADE,
+        related_name="student_overrides",
+    )
+
+    student = models.ForeignKey(
+        get_user_model(),
+        on_delete=models.CASCADE,
+    )
+
+    submission_cap = models.PositiveSmallIntegerField()
+
+    def __str__(self):
+        return f"Override for {self.student!r} @ Assignment {self.assignment!r}"
+
+
 class CooldownPeriod(models.Model):
     assignment = models.ForeignKey(
         Assignment,

tin/apps/assignments/tests/test_assignments.py

@@ -24,6 +24,9 @@ def test_create_assignment(client, course) -> None:
         "submission_limit_cooldown": "30",
         "is_quiz": False,
         "quiz_action": "2",
+        "submission_cap": "100",
+        "submission_cap_after_due": "100",
+        "use_submission_cap": False,
     }
     response = client.post(
         reverse("assignments:add", args=[course.id]),

tin/apps/assignments/tests/test_submission_cap.py

@@ -0,0 +1,153 @@
+from __future__ import annotations
+
+from datetime import datetime, timedelta
+
+import pytest
+from django.urls import reverse
+
+from tin.tests import is_redirect, login
+
+
+@login("student")
+def test_submission_cap(client, assignment):
+    assignment.use_submission_cap = True
+    assignment.submission_cap = 1
+    assignment.submission_cap_after_due = 1
+    assignment.due = datetime.today() + timedelta(days=1)
+    assignment.save()
+    code = "print('hello, world')"
+    assignment.save_grader_file(code)
+
+    def submit():
+        url = "assignments:submit"
+        return client.post(
+            reverse(url, args=[assignment.id]),
+            {"text": "print('I hate fun')"},
+        )
+
+    response = submit()
+    assert is_redirect(response), f"Expected redirect, got {response}"
+
+    # but now we've passed the cap
+    response = submit()
+    assert response.status_code == 403, f"Expected status code 403, got {response}"
+
+
+@login("student")
+def test_submission_cap_overdue(client, assignment):
+    assignment.use_submission_cap = True
+    assignment.submission_cap = 10000
+    assignment.submission_cap_after_due = 1
+    assignment.due = datetime.today() - timedelta(days=1)
+    assignment.save()
+    code = "print('hello, world')"
+    assignment.save_grader_file(code)
+
+    def submit():
+        url = "assignments:submit"
+        return client.post(
+            reverse(url, args=[assignment.id]),
+            {"text": "print('I hate fun')"},
+        )
+
+    response = submit()
+    assert is_redirect(response), f"Expected redirect, got {response}"
+
+    # but now we've passed the cap
+    response = submit()
+    assert response.status_code == 403, f"Expected status code 403, got {response}"
+
+
+@login("student")
+@pytest.mark.parametrize(
+    "due", (datetime.today() - timedelta(days=1), datetime.today() + timedelta(days=1))
+)
+def test_submission_cap_with_override(client, assignment, student, due):
+    """Test the submission cap with a per student override.
+
+    The override should take place regardless of the due date of the :class:`.Assignment`.
+    """
+    assignment.due = due
+    assignment.use_submission_cap = True
+    assignment.submission_cap = 1
+    assignment.submission_cap_after_due = 1
+    assignment.save()
+    code = "print('hello, world')"
+    assignment.save_grader_file(code)
+
+    # add student override
+    assignment.student_overrides.create(student=student, submission_cap=2)
+
+    def submit():
+        url = "assignments:submit"
+        return client.post(
+            reverse(url, args=[assignment.id]),
+            {"text": "print('I hate fun')"},
+        )
+
+    # first and second submission should be fine
+    response = submit()
+    assert is_redirect(response), f"Expected redirect, got {response}"
+    response = submit()
+    assert is_redirect(response), f"Expected redirect, got {response}"
+
+    # but now we've passed the cap for the student
+    response = submit()
+    assert response.status_code == 403, f"Expected status code 403, got {response}"
+
+
+@login("student")
+def test_submission_cap_on_quiz(client, quiz):
+    quiz.use_submission_cap = True
+    quiz.submission_cap = 1
+    quiz.submission_cap_after_due = 1
+    quiz.save()
+    code = "print('hello, world')"
+    quiz.save_grader_file(code)
+
+    def submit():
+        url = "assignments:quiz"
+        return client.post(
+            reverse(url, args=[quiz.id]),
+            {"text": "print('I hate fun')"},
+        )
+
+    response = submit()
+    assert is_redirect(response), f"Expected redirect, got {response}"
+    response = submit()
+    assert is_redirect(response), f"Expected submission cap to not affect quizzes (got {response})"
+
+
+@login("student")
+def test_submission_cap_not_used(client, assignment):
+    assignment.use_submission_cap = False
+    assignment.submission_cap = 1
+    assignment.submission_cap_after_due = 1
+    assignment.due = datetime.today() + timedelta(days=1)
+    assignment.save()
+
+    def submit():
+        url = "assignments:submit"
+        return client.post(
+            reverse(url, args=[assignment.id]),
+            {"text": "print('I hate fun')"},
+        )
+
+    # all submissions should be fine because use_submission_cap is False
+    response = submit()
+    assert is_redirect(response), f"Expected redirect, got {response}"
+    response = submit()
+    assert is_redirect(response), f"Expected redirect, got {response}"
+
+
+@login("teacher")
+def test_create_student_override(client, assignment, student):
+    response = client.post(
+        reverse("assignments:create_student_override", args=[assignment.id, student.id]),
+        {"submission_cap": 2},
+    )
+    assert is_redirect(response), f"Expected redirect, got {response}"
+
+    override = assignment.find_student_override(student)
+    assert override is not None
+    assert override.submission_cap == 2

tin/apps/assignments/urls.py

@@ -13,6 +13,12 @@
     path("<int:assignment_id>/delete", views.delete_view, name="delete"),
     path("<int:assignment_id>/grader", views.manage_grader_view, name="manage_grader"),
     path("<int:assignment_id>/grader/download", views.download_grader_view, name="download_grader"),
+    path("<int:assignment_id>/manage_students", views.manage_students_view, name="manage_students"),
+    path(
+        "<int:assignment_id>/manage_students/<int:student_id>",
+        views.manage_student,
+        name="create_student_override",
+    ),
     path("<int:assignment_id>/files", views.manage_files_view, name="manage_files"),
     path(
         "<int:assignment_id>/files/download/<int:file_id>",