Resolve "Make exam a many to many field on StudentInfo model"

core/migrations/0005_auto_20200707_1456.py

+# Generated by Django 2.2.12 on 2020-07-07 14:56
+
+import core.models.user_account
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0004_feedback_modified'),
+    ]
+
+    operations = [
+        migrations.RemoveField(
+            model_name='studentinfo',
+            name='exam',
+        ),
+        migrations.RemoveField(
+            model_name='studentinfo',
+            name='passes_exam',
+        ),
+        migrations.RemoveField(
+            model_name='studentinfo',
+            name='total_score',
+        ),
+        migrations.AlterField(
+            model_name='useraccount',
+            name='exercise_groups',
+            field=models.ManyToManyField(blank=True, default=core.models.user_account.group_default, related_name='users', to='core.Group'),
+        ),
+        migrations.CreateModel(
+            name='StudentsExam',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('total_score', models.PositiveIntegerField(default=0)),
+                ('passes_exam', models.BooleanField(default=False)),
+                ('exam', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='exam', to='core.ExamType')),
+                ('student', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='students', to='core.StudentInfo')),
+            ],
+        ),
+        migrations.AddField(
+            model_name='studentinfo',
+            name='exams',
+            field=models.ManyToManyField(blank=True, related_name='exams', to='core.StudentsExam'),
+        ),
+    ]

core/migrations/0006_auto_20200810_1115.py

+# Generated by Django 2.2.12 on 2020-08-10 11:15
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0005_auto_20200707_1456'),
+    ]
+
+    operations = [
+        migrations.RenameModel(
+            old_name='StudentsExam',
+            new_name='ExamInfo',
+        ),
+    ]

core/migrations/0007_auto_20200922_1026.py

+# Generated by Django 2.2.12 on 2020-09-22 10:26
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0006_auto_20200810_1115'),
+    ]
+
+    operations = [
+        migrations.RemoveField(
+            model_name='studentinfo',
+            name='exams',
+        ),
+        migrations.AlterField(
+            model_name='examinfo',
+            name='student',
+            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='exams', to='core.StudentInfo'),
+        ),
+    ]

core/migrations/0008_auto_20200922_1148.py

+# Generated by Django 2.2.12 on 2020-09-22 11:48
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0007_auto_20200922_1026'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='examinfo',
+            name='exam',
+            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='exam_infos', to='core.ExamType'),
+        ),
+    ]

core/migrations/0009_submissiontype_exam_type.py

+# Generated by Django 2.2.16 on 2020-10-22 11:57
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0008_auto_20200922_1148'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='submissiontype',
+            name='exam_type',
+            field=models.ForeignKey(null=True, on_delete=django.db.models.deletion.CASCADE, related_name='submission_types', to='core.ExamType'),
+        ),
+    ]

core/migrations/0010_group_examtype.py

+# Generated by Django 2.2.16 on 2020-11-03 11:54
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0009_submissiontype_exam_type'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='group',
+            name='examType',
+            field=models.ForeignKey(null=True, on_delete=django.db.models.deletion.CASCADE, related_name='groups', to='core.ExamType'),
+        ),
+    ]

core/migrations/0011_auto_20201103_1211.py

+# Generated by Django 2.2.16 on 2020-11-03 12:11
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0010_group_examtype'),
+    ]
+
+    operations = [
+        migrations.RenameField(
+            model_name='group',
+            old_name='examType',
+            new_name='exam_type',
+        ),
+    ]

core/migrations/0012_auto_20201103_1228.py

+# Generated by Django 2.2.16 on 2020-11-03 12:28
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0011_auto_20201103_1211'),
+    ]
+
+    operations = [
+        migrations.AlterModelOptions(
+            name='group',
+            options={'verbose_name': 'Group', 'verbose_name_plural': 'Groups'},
+        ),
+    ]

core/migrations/0013_auto_20201103_1248.py

+# Generated by Django 2.2.16 on 2020-11-03 12:48
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0012_auto_20201103_1228'),
+    ]
+
+    operations = [
+        migrations.AlterModelOptions(
+            name='group',
+            options={},
+        ),
+        migrations.RemoveField(
+            model_name='group',
+            name='exam_type',
+        ),
+    ]

core/migrations/0014_merge_20201123_1252.py

+# Generated by Django 3.1.3 on 2020-11-23 12:52
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0013_auto_20201103_1248'),
+        ('core', '0006_auto_20201027_1234'),
+    ]
+
+    operations = [
+    ]

core/migrations/0015_group_exam_type.py

+# Generated by Django 3.1.7 on 2021-09-02 11:36
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0014_merge_20201123_1252'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='group',
+            name='exam_type',
+            field=models.ForeignKey(null=True, on_delete=django.db.models.deletion.CASCADE, related_name='groups', to='core.examtype'),
+        ),
+    ]

core/migrations/0016_auto_20210902_1140.py

+# Generated by Django 3.1.7 on 2021-09-02 11:40
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0015_group_exam_type'),
+    ]
+
+    operations = [
+        migrations.RenameField(
+            model_name='group',
+            old_name='exam_type',
+            new_name='exam',
+        ),
+    ]

core/models/__init__.py

@@ -3,7 +3,7 @@ from .exam_type import ExamType  # noqa
 from .submission_type import SubmissionType, SolutionComment  # noqa
 from .user_account import UserAccount, TutorReviewerManager  # noqa
 from .user_account import UserAccount, TutorReviewerManager  # noqa
-from .student_info import StudentInfo, random_matrikel_no  # noqa
+from .student_info import StudentInfo, random_matrikel_no, ExamInfo  # noqa
 from .test import Test  # noqa
 from .submission import Submission, MetaSubmission  # noqa
 from .feedback import Feedback, FeedbackComment  # noqa

core/models/group.py

 from django.db import models
+from core.models.exam_type import ExamType
 import uuid
 
 
@@ -7,3 +8,7 @@ class Group(models.Model):
                                 default=uuid.uuid4,
                                 editable=False)
     name = models.CharField(max_length=120)
+    exam = models.ForeignKey(ExamType,
+                             on_delete=models.CASCADE,
+                             related_name='groups',
+                             null=True)

core/models/student_info.py

@@ -7,11 +7,11 @@ from typing import Dict
 import constance
 from django.contrib.auth import get_user_model
 from django.db import models
-from django.db.models import (BooleanField, Case, F,
-                              QuerySet, Sum, Value, When)
+from django.db.models import BooleanField, F, When, Sum, QuerySet, Value, Case
 from django.db.models.functions import Coalesce
 
 from core.models.submission_type import SubmissionType
+from core.models.exam_type import ExamType
 
 log = logging.getLogger(__name__)
 config = constance.config
@@ -26,6 +26,42 @@ def random_matrikel_no() -> str:
     return str(10_000_000 + randrange(90_000_000))
 
 
+class ExamInfo(models.Model):
+    exam = models.ForeignKey(ExamType,
+                             on_delete=models.CASCADE,
+                             related_name='exam_infos',
+                             null=False)
+
+    student = models.ForeignKey('StudentInfo',
+                                on_delete=models.CASCADE,
+                                related_name='exams',
+                                null=False)
+
+    total_score = models.PositiveIntegerField(default=0)
+    passes_exam = models.BooleanField(default=False)
+
+    def update_total_score(self):
+        ''' This helper is invoked after feedback changes '''
+        self.total_score = self.student.submissions.aggregate(
+            Sum('feedback__score'))['feedback__score__sum'] or 0
+        if self.exam is not None:
+            self.passes_exam = self.total_score >= self.exam.pass_score
+        self.save()
+
+    def score_per_submission(self) -> Dict[str, int]:
+        """ TODO: get rid of it and use an annotation. """
+        if self.student.submissions.all():
+            return OrderedDict({
+                s.type.name: s.feedback.score if hasattr(s, 'feedback') else 0
+                for s in self.student.submissions.filter(type__exam_type=self.exam)
+                .order_by('type__name')
+            })
+
+        return OrderedDict({
+            t.name: 0 for t in SubmissionType.objects.all()
+        })
+
+
 class StudentInfo(models.Model):
     """
     The StudentInfo model includes all information of a student, that we got
@@ -36,8 +72,9 @@ class StudentInfo(models.Model):
     associated user model.
 
     Attributes:
-        exam (ForeignKey):
-            Which module the student wants to be graded in
+        exams (ManyToManyField):
+            Module the student wants te be graded in, or different exercise
+            assignments for one module.
 
         has_logged_in (BooleanField):
             Login is permitted once. If this is set the user can not log in.
@@ -52,37 +89,15 @@ class StudentInfo(models.Model):
     matrikel_no = models.CharField(unique=True,
                                    max_length=30,
                                    default=random_matrikel_no)
-    exam = models.ForeignKey('ExamType',
-                             on_delete=models.CASCADE,
-                             related_name='students',
-                             null=False)
+
     user = models.OneToOneField(get_user_model(),
                                 on_delete=models.CASCADE,
                                 related_name='student')
 
-    # Managed by signals
-    total_score = models.PositiveIntegerField(default=0)
-    passes_exam = models.BooleanField(default=False)
-
-    def update_total_score(self):
-        ''' This helper is invoked after feedback changes '''
-        self.total_score = self.submissions.aggregate(
-            Sum('feedback__score'))['feedback__score__sum'] or 0
-        if self.exam is not None:
-            self.passes_exam = self.total_score >= self.exam.pass_score
-        self.save()
-
-    def score_per_submission(self) -> Dict[str, int]:
-        """ TODO: get rid of it and use an annotation. """
-        if self.submissions.all():
-            return OrderedDict({
-                s.type.name: s.feedback.score if hasattr(s, 'feedback') else 0
-                for s in self.submissions.order_by('type__name')
-            })
-
-        return OrderedDict({
-            t.name: 0 for t in SubmissionType.objects.all()
-        })
+    def add_exam(self, exam):
+        exam_info = ExamInfo(exam=exam, student=self)
+        exam_info.save()
+        self.exams.add(exam_info)
 
     @classmethod
     def get_annotated_score_submission_list(cls) -> QuerySet:

core/models/submission_type.py

@@ -6,6 +6,8 @@ from django.db import models
 from django.db.models import (Case, Count, IntegerField, Q,
                               Value, When)
 from django.db.models.query import QuerySet
+from core.models.exam_type import ExamType
+
 
 log = logging.getLogger(__name__)
 config = constance.config
@@ -56,6 +58,10 @@ class SubmissionType(models.Model):
     full_score = models.PositiveIntegerField(default=0)
     description = models.TextField()
     solution = models.TextField()
+    exam_type = models.ForeignKey(ExamType,
+                                  on_delete=models.CASCADE,
+                                  related_name='submission_types',
+                                  null=True)
     programming_language = models.CharField(max_length=25,
                                             choices=LANGUAGE_CHOICES,
                                             default=C)

core/serializers/__init__.py

 from .common_serializers import *  # noqa
-from .group import GroupSerializer  # noqa
 from .submission_type import (SubmissionTypeListSerializer, SubmissionTypeSerializer,  # noqa
                               SolutionCommentSerializer)  # noqa
 from .feedback import (FeedbackSerializer, FeedbackWithStudentSerializer, # noqa

core/serializers/common_serializers.py

@@ -8,7 +8,6 @@ from rest_framework import serializers
 from rest_framework.utils import html
 
 from core import models
-from core.serializers.group import GroupSerializer
 
 from .generic import DynamicFieldsModelSerializer
 
@@ -23,6 +22,14 @@ class ExamSerializer(DynamicFieldsModelSerializer):
                   'pass_score', 'pass_only',)
 
 
+class GroupSerializer(serializers.ModelSerializer):
+    exam = ExamSerializer(many=False)
+
+    class Meta:
+        model = models.Group
+        fields = ('pk', 'name', 'exam')
+
+
 class TestSerializer(DynamicFieldsModelSerializer):
 
     class Meta:

core/serializers/group.py

-from rest_framework import serializers
-
-from core.models import Group
-
-
-class GroupSerializer(serializers.ModelSerializer):
-    class Meta:
-        model = Group
-        fields = ('pk', 'name')

core/serializers/student.py

 from rest_framework import serializers
 
-from core.models import StudentInfo
+from core.models import StudentInfo, ExamInfo
 from core.serializers import DynamicFieldsModelSerializer, ExamSerializer
 from core.serializers.submission import (SubmissionListSerializer,
                                          SubmissionNoTextFieldsSerializer,
                                          SubmissionNoTypeSerializer)
 
 
+class ExamInfoListSerializer(DynamicFieldsModelSerializer):
+
+    class Meta:
+        model = ExamInfo
+        fields = ('exam', 'student', 'total_score', 'passes_exam')
+
+
 class StudentInfoSerializer(DynamicFieldsModelSerializer):
     name = serializers.ReadOnlyField(source='user.fullname')
     matrikel_no = serializers.ReadOnlyField(source='user.matrikel_no')
-    exam = ExamSerializer()
+    exams = ExamInfoListSerializer(many=True)
     submissions = SubmissionListSerializer(many=True)
 
     class Meta:
@@ -19,16 +26,15 @@ class StudentInfoSerializer(DynamicFieldsModelSerializer):
                   'name',
                   'user',
                   'matrikel_no',
-                  'exam',
                   'submissions',
-                  'passes_exam')
+                  'exams')
 
 
 class StudentInfoForListViewSerializer(DynamicFieldsModelSerializer):
     name = serializers.ReadOnlyField(source='user.fullname')
     user = serializers.ReadOnlyField(source='user.username')
     user_pk = serializers.ReadOnlyField(source='user.pk')
-    exam = serializers.ReadOnlyField(source='exam.module_reference')
+    exams = serializers.ReadOnlyField(source='exams.module_reference')
     submissions = SubmissionNoTextFieldsSerializer(many=True)
     is_active = serializers.BooleanField(source='user.is_active')
 
@@ -38,10 +44,9 @@ class StudentInfoForListViewSerializer(DynamicFieldsModelSerializer):
                   'name',
                   'user',
                   'user_pk',
-                  'exam',
+                  'exams',
                   'submissions',
                   'matrikel_no',
-                  'passes_exam',
                   'is_active')
 
 
@@ -49,7 +54,7 @@ class StudentExportSerializer(DynamicFieldsModelSerializer):
     name = serializers.ReadOnlyField(source='user.fullname')
     user = serializers.ReadOnlyField(source='user.username')
     user_pk = serializers.ReadOnlyField(source='user.pk')
-    exam = serializers.ReadOnlyField(source='exam.pk')
+    exams = ExamInfoListSerializer(many=True)
     email = serializers.ReadOnlyField(source='user.email')
     is_active = serializers.BooleanField(source='user.is_active')
     submissions = SubmissionNoTypeSerializer(many=True)
@@ -60,9 +65,17 @@ class StudentExportSerializer(DynamicFieldsModelSerializer):
                   'name',
                   'user',
                   'user_pk',
-                  'exam',
+                  'exams',
                   'email',
                   'submissions',
                   'matrikel_no',
-                  'passes_exam',
                   'is_active')
+
+
+class ExamInfoSerializer(DynamicFieldsModelSerializer):
+    exam = ExamSerializer()
+    student = StudentInfoSerializer()
+
+    class Meta:
+        model = ExamInfo
+        fields = ('exam', 'student', 'total_score', 'passes_exam')