zulip/zerver/migrations/0287_clear_duplicate_reacti...

39 lines
1.3 KiB
Python

from django.db import migrations
from django.db.backends.base.schema import BaseDatabaseSchemaEditor
from django.db.migrations.state import StateApps
from django.db.models import Count
def clear_duplicate_reactions(apps: StateApps, schema_editor: BaseDatabaseSchemaEditor) -> None:
"""Zulip's data model for reactions has enforced via code,
nontransactionally, that they can only react with one emoji_code
for a given reaction_type. This fixes any that were stored in the
database via a race; the next migration will add the appropriate
database-level unique constraint.
"""
Reaction = apps.get_model("zerver", "Reaction")
duplicate_reactions = (
Reaction.objects.all()
.values("user_profile_id", "message_id", "reaction_type", "emoji_code")
.annotate(Count("id"))
.filter(id__count__gt=1)
)
for duplicate_reaction in duplicate_reactions:
duplicate_reaction.pop("id__count")
to_cleanup = Reaction.objects.filter(**duplicate_reaction)[1:]
for reaction in to_cleanup:
reaction.delete()
class Migration(migrations.Migration):
dependencies = [
("zerver", "0286_merge_0260_0285"),
]
operations = [
migrations.RunPython(
clear_duplicate_reactions, reverse_code=migrations.RunPython.noop, elidable=True
),
]