fix: anonymize

codeforlife/user/fixtures/legacy.json

@@ -986,10 +986,10 @@
     "pk": 20,
     "fields": {
       "_first_name_enc": "ZmFrZV9lbmM6kEW6JpB05mjWAPE/xrxMrbFNoyD6ZBNVl+YCZI/q3+LRROg=",
-      "_first_name_hash": "1dbd289e95b4925fc85eff99d7e879b2033f60182e05872f8665ff271d0d337c",
+      "_first_name_hash": "",
       "_last_name_enc": "ZmFrZV9lbmM6gwxaGy9/aDQWDEVUwUverJ6wmk3ohaTkvF5GYq6koNg=",
       "_username_enc": "ZmFrZV9lbmM6kUOy1ae7Y1ElSiAiDXnKIZxPkOs1saBSjmH+UCEThmkOR7lKe9Nlmza/K+mW1Slr0UutzlVaqMLU3yWT",
-      "_username_hash": "daa37b0878d74480285044dccc67750ad597b99719dc7323462cbe16e0b0271d",
+      "_username_hash": "",
       "date_joined": "2026-02-04T16:02:37.614Z",
       "dek": "ZmFrZV9lbmM6Ct68dRt74lesvjRcTVtlbUlPC8xt85anig+MaarMMZAUvcFmkJmno57KkQUR8S5/o5ElV9Bpn3RDpxeS",
       "groups": [],

codeforlife/user/migrations/0006_client_side_encryption_part_4.py

@@ -1,7 +1,5 @@
 from django.db import migrations
 
-from ...models.fields import EncryptedTextField, Sha256Field
-
 user_migrations = [
     # Username
     migrations.RemoveField(

codeforlife/user/migrations/0007_empty_hash_when_inactive.py

@@ -0,0 +1,146 @@
+import typing as t
+
+from django.db import migrations
+from django.db.migrations.state import StateApps
+from django.db.models import CheckConstraint, Model, Q
+
+
+def set_hash_fields_to_empty(apps: StateApps, _):
+    """
+    Set hash fields to empty for inactive users, classes, schools, and school
+    teacher invitations.
+    """
+
+    User: t.Type[Model] = apps.get_model("user", "User")
+    Class: t.Type[Model] = apps.get_model("user", "Class")
+    School: t.Type[Model] = apps.get_model("user", "School")
+    SchoolTeacherInvitation: t.Type[Model] = apps.get_model(
+        "user", "SchoolTeacherInvitation"
+    )
+
+    is_not_active = Q(is_active=False)
+
+    User.objects.filter(is_not_active).update(
+        _username_hash="", _email_hash="", _first_name_hash=""
+    )
+
+    Class.objects.filter(is_not_active).update(_name_enc=b"", _name_hash="")
+
+    School.objects.filter(is_not_active).update(_name_hash="")
+
+    SchoolTeacherInvitation.objects.filter(is_not_active).update(
+        _invited_teacher_first_name_enc=b"",
+        _invited_teacher_last_name_enc=b"",
+        _invited_teacher_email_enc=b"",
+        _token_hash="",
+    )
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("auth", "0012_alter_user_first_name_max_length"),
+        ("user", "0006_client_side_encryption_part_4"),
+    ]
+
+    operations = [
+        migrations.RunPython(set_hash_fields_to_empty),
+        migrations.AddConstraint(
+            model_name="class",
+            constraint=CheckConstraint(
+                condition=Q(
+                    ("is_active", True), ("_name_enc", b""), _connector="OR"
+                ),
+                name="klass__name_enc_non_empty_when_inactive",
+            ),
+        ),
+        migrations.AddConstraint(
+            model_name="class",
+            constraint=CheckConstraint(
+                condition=Q(
+                    ("is_active", True), ("_name_hash", ""), _connector="OR"
+                ),
+                name="klass__name_hash_non_empty_when_inactive",
+            ),
+        ),
+        migrations.AddConstraint(
+            model_name="school",
+            constraint=CheckConstraint(
+                condition=Q(
+                    ("is_active", True), ("_name_hash", ""), _connector="OR"
+                ),
+                name="school__name_hash_non_empty_when_inactive",
+            ),
+        ),
+        migrations.AddConstraint(
+            model_name="schoolteacherinvitation",
+            constraint=CheckConstraint(
+                condition=Q(
+                    ("is_active", True),
+                    ("_invited_teacher_first_name_enc", b""),
+                    _connector="OR",
+                ),
+                name="school_teacher_invitation__invited_teacher_first_name_enc_non_empty_when_inactive",
+            ),
+        ),
+        migrations.AddConstraint(
+            model_name="schoolteacherinvitation",
+            constraint=CheckConstraint(
+                condition=Q(
+                    ("is_active", True),
+                    ("_invited_teacher_last_name_enc", b""),
+                    _connector="OR",
+                ),
+                name="school_teacher_invitation__invited_teacher_last_name_enc_non_empty_when_inactive",
+            ),
+        ),
+        migrations.AddConstraint(
+            model_name="schoolteacherinvitation",
+            constraint=CheckConstraint(
+                condition=Q(
+                    ("is_active", True),
+                    ("_invited_teacher_email_enc", b""),
+                    _connector="OR",
+                ),
+                name="school_teacher_invitation__invited_teacher_email_enc_non_empty_when_inactive",
+            ),
+        ),
+        migrations.AddConstraint(
+            model_name="schoolteacherinvitation",
+            constraint=CheckConstraint(
+                condition=Q(
+                    ("is_active", True), ("_token_hash", ""), _connector="OR"
+                ),
+                name="school_teacher_invitation__token_hash_non_empty_when_inactive",
+            ),
+        ),
+        migrations.AddConstraint(
+            model_name="user",
+            constraint=CheckConstraint(
+                condition=Q(
+                    ("is_active", True), ("_email_hash", ""), _connector="OR"
+                ),
+                name="user__email_hash_non_empty_when_inactive",
+            ),
+        ),
+        migrations.AddConstraint(
+            model_name="user",
+            constraint=CheckConstraint(
+                condition=Q(
+                    ("is_active", True), ("_username_hash", ""), _connector="OR"
+                ),
+                name="user__username_hash_non_empty_when_inactive",
+            ),
+        ),
+        migrations.AddConstraint(
+            model_name="user",
+            constraint=CheckConstraint(
+                condition=Q(
+                    ("is_active", True),
+                    ("_first_name_hash", ""),
+                    _connector="OR",
+                ),
+                name="user__first_name_hash_non_empty_when_inactive",
+            ),
+        ),
+    ]

codeforlife/user/models/klass.py

@@ -234,7 +234,9 @@ def get_requests_message(self):
     def anonymise(self):
         """Anonymise the class."""
         self.is_active = False
-        self.save()
+        self._name_enc = b""
+        self._name_hash = ""
+        self.save(update_fields=["is_active", "_name_enc", "_name_hash"])
 
         # Remove independent students' requests to join this class
         # pylint: disable-next=no-member
@@ -248,6 +250,14 @@ class Meta(TypedModelMeta):
                 condition=~models.Q(_access_code_hash=""),
                 name="unique_access_code_hash_non_empty",
             ),
+            models.CheckConstraint(
+                condition=models.Q(is_active=True) | models.Q(_name_enc=b""),
+                name="klass__name_enc_non_empty_when_inactive",
+            ),
+            models.CheckConstraint(
+                condition=models.Q(is_active=True) | models.Q(_name_hash=""),
+                name="klass__name_hash_non_empty_when_inactive",
+            ),
         ]
 
     @property

codeforlife/user/models/other.py

@@ -439,6 +439,43 @@ class Meta:
                 fields=["_token_hash"],
                 name="unique_token_hash_non_empty",
             ),
+            models.CheckConstraint(
+                condition=(
+                    models.Q(is_active=True)
+                    | models.Q(_invited_teacher_first_name_enc=b"")
+                ),
+                name=(
+                    "school_teacher_invitation__"
+                    "invited_teacher_first_name_enc_non_empty_when_inactive"
+                ),
+            ),
+            models.CheckConstraint(
+                condition=(
+                    models.Q(is_active=True)
+                    | models.Q(_invited_teacher_last_name_enc=b"")
+                ),
+                name=(
+                    "school_teacher_invitation__"
+                    "invited_teacher_last_name_enc_non_empty_when_inactive"
+                ),
+            ),
+            models.CheckConstraint(
+                condition=(
+                    models.Q(is_active=True)
+                    | models.Q(_invited_teacher_email_enc=b"")
+                ),
+                name=(
+                    "school_teacher_invitation__"
+                    "invited_teacher_email_enc_non_empty_when_inactive"
+                ),
+            ),
+            models.CheckConstraint(
+                condition=models.Q(is_active=True) | models.Q(_token_hash=""),
+                name=(
+                    "school_teacher_invitation__"
+                    "token_hash_non_empty_when_inactive"
+                ),
+            ),
         ]
 
     @property
@@ -455,11 +492,20 @@ def __str__(self):
 
     def anonymise(self):
         """Anonymise the invitation."""
-        self.invited_teacher_first_name = ""
-        self.invited_teacher_last_name = ""
-        self.invited_teacher_email = ""
+        self._invited_teacher_first_name_enc = b""
+        self._invited_teacher_last_name_enc = b""
+        self._invited_teacher_email_enc = b""
+        self._token_hash = ""
         self.is_active = False
-        self.save()
+        self.save(
+            update_fields=[
+                "_invited_teacher_first_name_enc",
+                "_invited_teacher_last_name_enc",
+                "_invited_teacher_email_enc",
+                "_token_hash",
+                "is_active",
+            ]
+        )
 
     @property
     def dek_aead(self):

codeforlife/user/models/school.py

@@ -139,6 +139,10 @@ class Meta(TypedModelMeta):
                 fields=["_name_hash"],
                 name="unique_name_hash_non_empty",
             ),
+            models.CheckConstraint(
+                condition=models.Q(is_active=True) | models.Q(_name_hash=""),
+                name="school__name_hash_non_empty_when_inactive",
+            ),
         ]
 
     def __str__(self):
@@ -168,4 +172,5 @@ def anonymise(self):
         """Anonymize the school."""
         self.dek = None
         self.is_active = False
-        self.save(update_fields=["dek", "is_active"])
+        self._name_hash = ""
+        self.save(update_fields=["dek", "is_active", "_name_hash"])

codeforlife/user/models/user/user.py

@@ -311,6 +311,22 @@ class Meta(TypedModelMeta):
                 fields=["_username_hash"],
                 name="unique_username_hash_non_empty",
             ),
+            models.CheckConstraint(
+                condition=models.Q(is_active=True) | models.Q(_email_hash=""),
+                name="user__email_hash_non_empty_when_inactive",
+            ),
+            models.CheckConstraint(
+                condition=(
+                    models.Q(is_active=True) | models.Q(_username_hash="")
+                ),
+                name="user__username_hash_non_empty_when_inactive",
+            ),
+            models.CheckConstraint(
+                condition=(
+                    models.Q(is_active=True) | models.Q(_first_name_hash="")
+                ),
+                name="user__first_name_hash_non_empty_when_inactive",
+            ),
         ]
 
     # TODO: remove in new schema
@@ -427,7 +443,18 @@ def anonymize(self):
         """Anonymize the user."""
         self.dek = None
         self.is_active = False
-        self.save(update_fields=["dek", "is_active"])
+        self._username_hash = ""
+        self._email_hash = ""
+        self._first_name_hash = ""
+        self.save(
+            update_fields=[
+                "dek",
+                "is_active",
+                "_username_hash",
+                "_email_hash",
+                "_first_name_hash",
+            ]
+        )
 
         # self.userprofile.google_refresh_token = None
         # self.userprofile.google_sub = None