Fix regression with publish task

contentcuration/contentcuration/models.py

@@ -2565,14 +2565,13 @@ def serialize_to_change_dict(self):
 class CustomTaskMetadata(models.Model):
     # Task_id for reference
     task_id = models.CharField(
-        max_length=255,  # Adjust the max_length as needed
+        max_length=255,
         unique=True,
     )
-    # user shouldn't be null, but in order to append the field, this needs to be allowed
     user = models.ForeignKey(settings.AUTH_USER_MODEL, related_name="tasks", on_delete=models.CASCADE, null=True)
     channel_id = DjangoUUIDField(db_index=True, null=True, blank=True)
     progress = models.IntegerField(null=True, blank=True, validators=[MinValueValidator(0), MaxValueValidator(100)])
-    # a hash of the task name and kwargs for identifying repeat tasks
+    # A hash of the task name and kwargs for identifying repeat tasks
     signature = models.CharField(null=True, blank=False, max_length=32)
     date_created = models.DateTimeField(
         auto_now_add=True,
@@ -2582,7 +2581,6 @@ class CustomTaskMetadata(models.Model):
 
     class Meta:
         indexes = [
-            # add index that matches query usage for signature
             models.Index(
                 fields=['signature'],
                 name='task_result_signature',

contentcuration/contentcuration/tests/test_exportchannel.py

@@ -1,13 +1,17 @@
 from __future__ import absolute_import
 
+import json
 import os
 import random
 import string
 import tempfile
+import uuid
 
 import pytest
+from celery import states
 from django.core.management import call_command
 from django.db import connections
+from django_celery_results.models import TaskResult
 from kolibri_content import models as kolibri_models
 from kolibri_content.router import cleanup_content_database_connection
 from kolibri_content.router import get_active_content_database
@@ -29,6 +33,8 @@
 from .testdata import slideshow
 from .testdata import thumbnail_bytes
 from contentcuration import models as cc
+from contentcuration.models import CustomTaskMetadata
+from contentcuration.utils.celery.tasks import generate_task_signature
 from contentcuration.utils.publish import ChannelIncompleteError
 from contentcuration.utils.publish import convert_channel_thumbnail
 from contentcuration.utils.publish import create_content_database
@@ -37,6 +43,7 @@
 from contentcuration.utils.publish import map_prerequisites
 from contentcuration.utils.publish import MIN_SCHEMA_VERSION
 from contentcuration.utils.publish import set_channel_icon_encoding
+from contentcuration.viewsets.base import create_change_tracker
 
 pytestmark = pytest.mark.django_db
 
@@ -553,3 +560,40 @@ def test_fill_published_fields(self):
         self.assertTrue(channel.published_data)
         self.assertIsNotNone(channel.published_data.get(0))
         self.assertEqual(channel.published_data[0]['version_notes'], version_notes)
+
+
+class PublishFailCleansUpTaskObjects(StudioTestCase):
+    def setUp(self):
+        super(PublishFailCleansUpTaskObjects, self).setUpBase()
+
+    def test_failed_task_objects_cleaned_up_when_publishing(self):
+        channel_id = self.channel.id
+        task_name = 'export-channel'
+        task_id = uuid.uuid4().hex
+        pk = 'ab684452f2ad4ba6a1426d6410139f60'
+        table = 'channel'
+        task_kwargs = json.dumps({'pk': pk, 'table': table})
+        signature = generate_task_signature(task_name, task_kwargs=task_kwargs, channel_id=channel_id)
+
+        TaskResult.objects.create(
+            task_id=task_id,
+            status=states.FAILURE,
+            task_name=task_name,
+        )
+
+        CustomTaskMetadata.objects.create(
+            task_id=task_id,
+            channel_id=channel_id,
+            user=self.user,
+            signature=signature
+        )
+
+        assert TaskResult.objects.filter(task_id=task_id).exists()
+        assert CustomTaskMetadata.objects.filter(task_id=task_id).exists()
+
+        with create_change_tracker(pk, table, channel_id, self.user, task_name):
+            assert not TaskResult.objects.filter(task_id=task_id).exists()
+            assert not CustomTaskMetadata.objects.filter(task_id=task_id).exists()
+            new_task_result = TaskResult.objects.filter(task_name=task_name, status=states.STARTED).first()
+            new_custom_task_metadata = CustomTaskMetadata.objects.get(channel_id=channel_id, user=self.user, signature=signature)
+            assert new_custom_task_metadata.task_id == new_task_result.task_id

contentcuration/contentcuration/viewsets/base.py

@@ -936,9 +936,12 @@ def create_change_tracker(pk, table, channel_id, user, task_name):
     # Clean up any previous tasks specific to this in case there were failures.
     signature = generate_task_signature(task_name, task_kwargs=task_kwargs, channel_id=channel_id)
 
-    task_id_to_delete = CustomTaskMetadata.objects.filter(channel_id=channel_id, signature=signature)
-    if task_id_to_delete:
-        TaskResult.objects.filter(task_id=task_id_to_delete, task_name=task_name).delete()
+    custom_task_metadata_qs = CustomTaskMetadata.objects.filter(channel_id=channel_id, signature=signature)
+    if custom_task_metadata_qs.exists():
+        task_result_qs = TaskResult.objects.filter(task_id=custom_task_metadata_qs[0].task_id, task_name=task_name)
+        if task_result_qs.exists():
+            task_result_qs[0].delete()
+        custom_task_metadata_qs[0].delete()
 
     task_id = uuid.uuid4().hex