Fix missing conversation meta (#1289)

* Don't assume ConversationMeta exists

* Set default marked_at dates to min datetime

karrot/conversations/api.py

@@ -262,7 +262,7 @@ def get_conversation(application):
         issue_serializer = IssueSerializer(issues, many=True, context=context)
         offer_serializer = OfferSerializer(offers, many=True, context=context)
         user_serializer = UserInfoSerializer(users, many=True, context=context)
-        meta = ConversationMeta.objects.get(user=request.user)
+        meta, _ = ConversationMeta.objects.get_or_create(user=request.user)
         meta_serializer = ConversationMetaSerializer(meta, context=self.get_serializer_context())
 
         return self.get_paginated_response(

karrot/conversations/migrations/0045_alter_conversationmeta_conversations_marked_at_and_more.py

@@ -0,0 +1,24 @@
+# Generated by Django 4.2.7 on 2024-03-06 09:56
+
+import datetime
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('conversations', '0044_alter_conversationmessageattachment_file_and_more'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='conversationmeta',
+            name='conversations_marked_at',
+            field=models.DateTimeField(default=datetime.datetime(1, 1, 1, 0, 0, tzinfo=datetime.timezone.utc)),
+        ),
+        migrations.AlterField(
+            model_name='conversationmeta',
+            name='threads_marked_at',
+            field=models.DateTimeField(default=datetime.datetime(1, 1, 1, 0, 0, tzinfo=datetime.timezone.utc)),
+        ),
+    ]

karrot/conversations/models.py

@@ -1,3 +1,4 @@
+from datetime import datetime
 from enum import Enum
 from uuid import uuid4
 
@@ -10,6 +11,7 @@
 from django.db.models.manager import BaseManager
 from django.utils import timezone
 from PIL import Image, UnidentifiedImageError
+from pytz import utc
 from versatileimagefield.fields import VersatileImageField
 from versatileimagefield.image_warmer import VersatileImageFieldWarmer
 
@@ -142,10 +144,13 @@ def supports_mentions(self):
         return self.type() is not None and self.type() != "private" and self.group is not None
 
 
+min_datetime = datetime.min.replace(tzinfo=utc)
+
+
 class ConversationMeta(BaseModel):
     user = models.OneToOneField(settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
-    conversations_marked_at = models.DateTimeField()
-    threads_marked_at = models.DateTimeField()
+    conversations_marked_at = models.DateTimeField(default=min_datetime)
+    threads_marked_at = models.DateTimeField(default=min_datetime)
 
 
 class ConversationParticipantQuerySet(models.QuerySet):