Switch PROTECT to CASCADE on module-related models

Relates to MS-830

server/assignments/models.py

@@ -23,7 +23,7 @@ class Assignment(index.Indexed, TimeStampedModel, GraphqlNodeMixin):
         get_user_model(), on_delete=models.PROTECT, null=True, blank=True
     )  # probably don't want to delete all assignments if a user gets deleted
     module = models.ForeignKey(
-        "books.Module", related_name="assignments", on_delete=models.PROTECT
+        "books.Module", related_name="assignments", on_delete=models.CASCADE
     )
     user_created = models.BooleanField(default=False)
     taskbase_id = models.CharField(max_length=255, null=True, blank=True)

server/books/models/snapshot.py

@@ -15,15 +15,12 @@ class ChapterSnapshot(models.Model):
     Captures the state of a chapter at the time when the snapshot was taken, for the school class that was selected
     for the user creating the snapshot
     """
+
     chapter = models.ForeignKey(
-        'books.Chapter',
+        "books.Chapter", related_name="chapter_snapshots", on_delete=models.CASCADE
-        related_name='chapter_snapshots',
-        on_delete=models.PROTECT
     )
     snapshot = models.ForeignKey(
-        'books.Snapshot',
+        "books.Snapshot", related_name="chapter_snapshots", on_delete=models.CASCADE
-        related_name='chapter_snapshots',
-        on_delete=models.CASCADE
     )
     title_hidden = models.BooleanField(default=False)
     description_hidden = models.BooleanField(default=False)
@@ -31,13 +28,12 @@ class ChapterSnapshot(models.Model):
 
 class ObjectiveGroupSnapshot(models.Model):
     objective_group = models.ForeignKey(
-        'objectives.ObjectiveGroup',
+        "objectives.ObjectiveGroup", on_delete=models.CASCADE
-        on_delete=models.CASCADE
     )
     snapshot = models.ForeignKey(
-        'books.Snapshot',
+        "books.Snapshot",
-        related_name='objective_group_snapshots',
+        related_name="objective_group_snapshots",
-        on_delete=models.CASCADE
+        on_delete=models.CASCADE,
     )
     hidden = models.BooleanField(default=False)
 
@@ -50,10 +46,16 @@ class SnapshotManager(models.Manager):
             ChapterSnapshot.objects.create(
                 chapter=chapter,
                 snapshot=snapshot,
-                title_hidden=chapter.title_hidden_for.filter(id=school_class.id).exists(),
+                title_hidden=chapter.title_hidden_for.filter(
-                description_hidden=chapter.description_hidden_for.filter(id=school_class.id).exists()
+                    id=school_class.id
+                ).exists(),
+                description_hidden=chapter.description_hidden_for.filter(
+                    id=school_class.id
+                ).exists(),
+            )
+            base_qs = ContentBlock.get_by_parent(chapter).filter(
+                contentblocksnapshot__isnull=True
             )
-            base_qs = ContentBlock.get_by_parent(chapter).filter(contentblocksnapshot__isnull=True)
             # Verlagsinhalte
             for content_block in base_qs.filter(user_created=False):
                 if content_block.hidden_for.filter(id=school_class.id).exists():
@@ -66,9 +68,9 @@ class SnapshotManager(models.Manager):
                     contents=content_block.contents,
                     type=content_block.type,
                     title=content_block.title,
-                    original_creator=content_block.owner
+                    original_creator=content_block.owner,
                 )
-                content_block.add_sibling(instance=new_content_block, pos='right')
+                content_block.add_sibling(instance=new_content_block, pos="right")
                 revision = new_content_block.save_revision()
                 revision.publish()
                 new_content_block.save()
@@ -91,7 +93,7 @@ class SnapshotManager(models.Manager):
                     snapshot=snapshot,
                     text=objective.text,
                     group=objective_group,
-                    order=objective.order
+                    order=objective.order,
                 )
 
         return snapshot
@@ -99,36 +101,27 @@ class SnapshotManager(models.Manager):
 
 class Snapshot(models.Model):
     module = models.ForeignKey(
-        'books.Module',
+        "books.Module", on_delete=models.CASCADE, related_name="snapshots"
-        on_delete=models.PROTECT,
-        related_name='snapshots'
-    )
-    chapters = models.ManyToManyField(
-        'books.Chapter',
-        through=ChapterSnapshot
     )
+    chapters = models.ManyToManyField("books.Chapter", through=ChapterSnapshot)
     hidden_content_blocks = models.ManyToManyField(
-        'books.ContentBlock',
+        "books.ContentBlock", related_name="hidden_for_snapshots"
-        related_name='hidden_for_snapshots'
     )
     created = models.DateTimeField(auto_now_add=True)
     creator = models.ForeignKey(get_user_model(), on_delete=models.SET_NULL, null=True)
     shared = models.BooleanField(default=False)
     objective_groups = models.ManyToManyField(
-        'objectives.ObjectiveGroup',
+        "objectives.ObjectiveGroup", through=ObjectiveGroupSnapshot, related_name="+"
-        through=ObjectiveGroupSnapshot,
-        related_name='+'
     )
     hidden_objectives = models.ManyToManyField(
-        'objectives.Objective',
+        "objectives.Objective", related_name="hidden_for_snapshots"
-        related_name='hidden_for_snapshots'
     )
     title = models.CharField(max_length=255, blank=True, null=True)
 
     objects = SnapshotManager()
 
     def __str__(self):
-        return f'Snapshot {self.id}'
+        return f"Snapshot {self.id}"
 
     def reset(self, user: User, selected_class: SchoolClass):
         for chapter in Chapter.get_by_parent(self.module):
@@ -136,7 +129,7 @@ class Snapshot(models.Model):
             default_content = Q(user_created=False)
             no_snapshot = Q(contentblocksnapshot__isnull=True)
             owner_user = Q(owner=user)
-            logger.info(f'resetting hidden properties for chapter {chapter.id}')
+            logger.info(f"resetting hidden properties for chapter {chapter.id}")
             chapter.title_hidden_for.remove(selected_class)
             chapter.description_hidden_for.remove(selected_class)
 
@@ -149,7 +142,9 @@ class Snapshot(models.Model):
         for content_block in self.hidden_content_blocks.all():
             content_block.hidden_for.add(selected_class)
         for custom_content_block in self.custom_content_blocks.all():
-            custom_content_block.to_regular_content_block(owner=user, school_class=selected_class)
+            custom_content_block.to_regular_content_block(
+                owner=user, school_class=selected_class
+            )
         for chapter_snapshot in ChapterSnapshot.objects.filter(snapshot=self):
             chapter = chapter_snapshot.chapter
             if chapter_snapshot.title_hidden:

server/surveys/models.py

@@ -3,7 +3,6 @@ from django.db import models
 from django.db.models import JSONField
 from wagtail.snippets.models import register_snippet
 from wagtail.search import index
-from modelcluster.fields import ParentalKey
 
 from core.mixins import GraphqlNodeMixin
 
@@ -14,7 +13,7 @@ class Survey(models.Model, index.Indexed, GraphqlNodeMixin):
     module = models.ForeignKey(
         "books.Module",
         related_name="surveys",
-        on_delete=models.PROTECT,
+        on_delete=models.CASCADE,
         null=True,
         blank=True,
     )
@@ -41,7 +40,7 @@ class Answer(models.Model):
         get_user_model(), on_delete=models.CASCADE, related_name="answers"
     )
     data = JSONField()
-    survey = models.ForeignKey(Survey, on_delete=models.PROTECT, related_name="answers")
+    survey = models.ForeignKey(Survey, on_delete=models.CASCADE, related_name="answers")
 
     def __str__(self):
         return "{} - {}".format(self.owner.username, self.survey.title)