mirror of https://github.com/zulip/zulip.git
48 lines
2.1 KiB
Python
48 lines
2.1 KiB
Python
|
# -*- coding: utf-8 -*-
|
||
|
# Generated by Django 1.10.5 on 2017-04-13 22:12
|
||
|
|
||
|
from django.db import migrations
|
||
|
from django.db.backends.postgresql_psycopg2.schema import DatabaseSchemaEditor
|
||
|
from django.db.migrations.state import StateApps
|
||
|
from django.db.models import Count
|
||
|
|
||
|
def fix_duplicate_attachments(apps, schema_editor):
|
||
|
# type: (StateApps, DatabaseSchemaEditor) -> None
|
||
|
"""Migration 0041 had a bug, where if multiple messages referenced the
|
||
|
same attachment, rather than creating a single attachment object
|
||
|
for all of them, we would incorrectly create one for each message.
|
||
|
This results in exceptions looking up the Attachment object
|
||
|
corresponding to a file that was used in multiple messages that
|
||
|
predate migration 0041.
|
||
|
|
||
|
This migration fixes this by removing the duplicates, moving their
|
||
|
messages onto a single canonical Attachment object (per path_id).
|
||
|
"""
|
||
|
Attachment = apps.get_model('zerver', 'Attachment')
|
||
|
# Loop through all groups of Attachment objects with the same `path_id`
|
||
|
for group in Attachment.objects.values('path_id').annotate(Count('id')).order_by().filter(id__count__gt=1):
|
||
|
# Sort by the minimum message ID, to find the first attachment
|
||
|
attachments = sorted(list(Attachment.objects.filter(path_id=group['path_id']).order_by("id")),
|
||
|
key = lambda x: min(x.messages.all().values_list('id')[0]))
|
||
|
surviving = attachments[0]
|
||
|
to_cleanup = attachments[1:]
|
||
|
for a in to_cleanup:
|
||
|
# For each duplicate attachment, we transfer its messages
|
||
|
# to the canonical attachment object for that path, and
|
||
|
# then delete the original attachment.
|
||
|
for msg in a.messages.all():
|
||
|
surviving.messages.add(msg)
|
||
|
surviving.is_realm_public = surviving.is_realm_public or a.is_realm_public
|
||
|
surviving.save()
|
||
|
a.delete()
|
||
|
|
||
|
class Migration(migrations.Migration):
|
||
|
|
||
|
dependencies = [
|
||
|
('zerver', '0073_custom_profile_fields'),
|
||
|
]
|
||
|
|
||
|
operations = [
|
||
|
migrations.RunPython(fix_duplicate_attachments)
|
||
|
]
|