fix(submission): retain username in _submitted_by after submitting user has been deleted DEV-1211 (#6430)

### 📣 Summary
Ensure that submissions remain attributed to their original submitter
even if the user account is deleted, and that the `_submitted_by` value
continues to persist correctly during edits and bulk updates.

### 📖 Description
Previously, deleting a user caused all their submissions to lose the
`_submitted_by` reference or even be deleted, depending on ownership.
This PR ensures that:
- Submissions made by a deleted user on non-owned projects are retained.
- The `_submitted_by` field correctly persists the username of the
deleted user.
- Editing or bulk-updating those submissions does not remove or
overwrite the existing `_submitted_by` value.
- Bulk and single validation status updates correctly reference the
original `_submitted_by` username.

Author: rajpatel24

kobo/apps/audit_log/signals.py

@@ -6,6 +6,7 @@
 from django.dispatch import receiver
 from django_userforeignkey.request import get_current_request
 
+from kobo.apps.openrosa.libs.utils.common_tags import SUBMITTED_BY
 from kpi.constants import ASSET_TYPE_SURVEY, PERM_PARTIAL_SUBMISSIONS
 from kpi.models import Asset, ImportTask
 from kpi.tasks import import_in_background
@@ -76,14 +77,14 @@ def add_instance_to_request(instance, action):
     request = get_current_request()
     if request is None:
         return
-    if getattr(instance.asset.asset, 'id', None) is None:
+    if getattr(instance.xform.asset, 'id', None) is None:
         # if an XForm doesn't have a real associated Asset, ignore it
         return
     if getattr(request, 'instances', None) is None:
         request.instances = {}
     if getattr(request, 'asset', None) is None:
-        request.asset = instance.asset.asset
-    username = instance.user.username if instance.user else None
+        request.asset = instance.xform.asset
+    username = instance.json.get(SUBMITTED_BY)
     request.instances.update(
         {
             instance.id: SubmissionUpdate(

kobo/apps/kobo_auth/signals.py

@@ -1,10 +1,11 @@
 from django.conf import settings
-from django.db.models.signals import post_save
+from django.db.models.signals import post_save, pre_delete
 from django.dispatch import receiver
 from rest_framework.authtoken.models import Token
 
 from kobo.apps.kobo_auth.shortcuts import User
 from kobo.apps.openrosa.apps.main.models.user_profile import UserProfile
+from kobo.apps.openrosa.apps.viewer.models import ParsedInstance
 from kpi.deployment_backends.kc_access.utils import (
     grant_kc_model_level_perms,
     kc_transaction_atomic,
@@ -50,6 +51,16 @@ def default_permissions_post_save(sender, instance, created, raw, **kwargs):
     grant_default_model_level_perms(instance)
 
 
+@receiver(pre_delete, sender=User)
+def persist_submitted_by(sender, instance, **kwargs):
+    if kwargs.get('using') == settings.OPENROSA_DB_ALIAS:
+        # Give `instance` a better name to avoid confusion
+        deleted_user = instance
+        ParsedInstance.objects.filter(
+             instance__user_id=deleted_user.pk, submitted_by__isnull=True
+        ).update(submitted_by=deleted_user.username)
+
+
 @receiver(post_save, sender=User)
 def save_kobocat_user(sender, instance, created, raw, **kwargs):
     """

kobo/apps/openrosa/apps/logger/models/instance.py

@@ -147,6 +147,17 @@ def check_active(self, force):
         if not self.xform.user.is_active:
             raise AccountInactiveError()
 
+    def _get_submitted_by(self):
+        try:
+            parsed_instance = self.parsed_instance
+        except Instance.parsed_instance.RelatedObjectDoesNotExist:
+            pass
+        else:
+            parsed_instance.set_submitted_by(save=True)
+            return parsed_instance.submitted_by
+
+        return self.user.username if self.user is not None else None
+
     def _set_geom(self):
         xform = self.xform
         data_dictionary = xform.data_dictionary()
@@ -180,7 +191,7 @@ def _set_json(self):
 
         doc[SUBMISSION_TIME] = self.date_created.strftime(MONGO_STRFTIME)
         doc[XFORM_ID_STRING] = self._parser.get_xform_id_string()
-        doc[SUBMITTED_BY] = self.user.username if self.user is not None else None
+        doc[SUBMITTED_BY] = self._get_submitted_by()
         self.json = doc
 
     def _set_parser(self):
@@ -189,8 +200,9 @@ def _set_parser(self):
                 self.xml, self.xform.data_dictionary())
 
     def _set_survey_type(self):
-        self.survey_type, created = \
-            SurveyType.objects.get_or_create(slug=self.get_root_node_name())
+        self.survey_type, created = SurveyType.objects.get_or_create(
+            slug=self.get_root_node_name()
+        )
 
     def _set_uuid(self):
         if self.xml and not self.uuid:
@@ -279,8 +291,11 @@ def get_dict(self, force_new=False, flat=True):
         """Return a python object representation of this instance's XML."""
         self._set_parser()
 
-        return self._parser.get_flat_dict_with_attributes() if flat else\
-            self._parser.to_dict()
+        return (
+            self._parser.get_flat_dict_with_attributes()
+            if flat
+            else self._parser.to_dict()
+        )
 
     def get_full_dict(self):
         # TODO should we store all of these in the JSON no matter what?

kobo/apps/openrosa/apps/logger/tests/test_simple_submission.py

@@ -54,12 +54,21 @@ def _submit_at_hour(self, hour):
         except DuplicateInstanceError:
             pass
 
-    def _submit_simple_yes(self):
-        create_instance(self.user.username, TempFileProxy(
-            f'<?xml version=\'1.0\' ?><yes_or_no id="yes_or_no"><yesno>Yes<'
-            f'/yesno>'
-            f'<meta><instanceID>uuid:{str(uuid.uuid4())}</instanceID></meta>'
-            f'</yes_or_no>'), [])
+    def _submit_simple_yes(self, request=None):
+        return create_instance(
+            username=self.user.username,
+            xml_file=TempFileProxy(
+                f'<?xml version=\'1.0\' ?>'
+                f'<yes_or_no id="yes_or_no">'
+                f'  <yesno>Yes</yesno>'
+                f'  <meta>'
+                f'      <instanceID>uuid:{str(uuid.uuid4())}</instanceID>'
+                f'  </meta>'
+                f'</yes_or_no>'
+            ),
+            media_files=[],
+            request=request,
+        )
 
     def setUp(self):
         self.user = User.objects.create(username='admin', email='[email protected]')
@@ -150,3 +159,16 @@ def test_check_exceeded_limit_on_submission(self):
             self._submit_simple_yes()
             patched.assert_any_call(self.user, UsageType.SUBMISSION)
             patched.assert_any_call(self.user, UsageType.STORAGE_BYTES)
+
+    def test_parsed_instance_submitted_by_value(self):
+        class MockRequest:
+            pass
+
+        request = MockRequest()
+        request.user = self.user
+        instance = self._submit_simple_yes(request=request)
+        assert instance.parsed_instance.submitted_by == self.user.username
+
+        instance.delete()
+        instance = self._submit_simple_yes(request=None)
+        assert instance.parsed_instance.submitted_by is None

kobo/apps/openrosa/apps/logger/utils/instance.py

@@ -133,13 +133,13 @@ def set_instance_validation_statuses(
     if get_current_request() is not None:
         get_current_request().instances = {
             record['id']: SubmissionUpdate(
-                username=record['user__username'],
+                username=record['json'].get('_submitted_by'),
                 action='modify',
                 status=validation_status,
                 id=record['id'],
                 root_uuid=record['root_uuid'],
             )
-            for record in records_queryset.values('user__username', 'id', 'root_uuid')
+            for record in records_queryset.values('id', 'root_uuid', 'json')
         }
     updated_records_count = records_queryset.update(
         validation_status=new_validation_status

kobo/apps/openrosa/apps/viewer/migrations/0006_parsedinstance_submitted_by.py

@@ -0,0 +1,18 @@
+# Generated by Django 4.2.24 on 2025-10-29 06:41
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('viewer', '0005_alter_instancemodification_date_created_and_more'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='parsedinstance',
+            name='submitted_by',
+            field=models.CharField(blank=True, max_length=255, null=True),
+        ),
+    ]

kobo/apps/openrosa/apps/viewer/models/parsed_instance.py

@@ -81,6 +81,7 @@ class ParsedInstance(models.Model):
     # TODO: decide if decimal field is better than float field.
     lat = models.FloatField(null=True)
     lng = models.FloatField(null=True)
+    submitted_by = models.CharField(max_length=255, null=True, blank=True)
 
     @property
     def mongo_dict_override(self):
@@ -213,6 +214,14 @@ def query_mongo_no_paging(cls, query, fields, count=False):
 
         return cls._get_mongo_cursor(query, fields)
 
+    def set_submitted_by(self, save=False):
+        if not self.submitted_by and self.instance and self.instance.user:
+            self.submitted_by = self.instance.user.username
+            if save:
+                self.__class__.objects.filter(pk=self.pk).update(
+                    submitted_by=self.submitted_by
+                )
+
     @classmethod
     def _get_mongo_cursor(cls, query, fields):
         """
@@ -305,8 +314,7 @@ def to_dict_for_mongo(self):
             TAGS: list(self.instance.tags.names()),
             NOTES: self.get_notes(),
             VALIDATION_STATUS: self.instance.get_validation_status(),
-            SUBMITTED_BY: self.instance.user.username
-            if self.instance.user else None
+            SUBMITTED_BY: self.submitted_by
         }
 
         xform = self.instance.xform
@@ -325,6 +333,7 @@ def to_dict_for_mongo(self):
         return MongoHelper.to_safe_dict(d)
 
     def update_mongo(self, asynchronous=True):
+        self.set_submitted_by(save=True)
         d = self.to_dict_for_mongo()
         if d.get('_xform_id_string') is None:
             # if _xform_id_string, Instance could not be parsed.
@@ -406,6 +415,8 @@ def save(self, asynchronous=False, *args, **kwargs):
         self.start_time = None
         self.end_time = None
         self._set_geopoint()
+        if created:
+            self.set_submitted_by()
         super().save(*args, **kwargs)
 
         # insert into Mongo.

kobo/apps/trash_bin/utils/account.py

@@ -20,6 +20,7 @@
 from ..models.account import AccountTrash
 from ..models.project import ProjectTrash
 from ..utils.project import delete_asset
+from ...openrosa.apps.viewer.models import ParsedInstance
 
 
 def delete_account(account_trash: AccountTrash):
@@ -98,7 +99,6 @@ def delete_account(account_trash: AccountTrash):
                     user.delete()
 
                 AuditLog.objects.create(**audit_log_params)
-
                 delete_kc_user(user.username)
 
                 if user.username:

kpi/tests/api/v1/test_api_submissions.py

@@ -198,6 +198,14 @@ def test_edit_submission_twice(self):
     def test_get_multiple_edit_links_and_attempt_submit_edits(self):
         pass
 
+    @pytest.mark.skip(reason='Only usable in v2')
+    def test_submitted_by_persist_after_edit(self):
+        pass
+
+    @pytest.mark.skip(reason='Only usable in v2')
+    def test_submitted_by_persists_for_shared_submitter(self):
+        pass
+
 
 class SubmissionValidationStatusApiTests(
     test_api_submissions.SubmissionValidationStatusApiTests