Files
bugsink/snappea/migrations/0001_initial.py
2024-08-29 10:23:10 +02:00

51 lines
1.8 KiB
Python

import logging
from django.db import migrations
logger = logging.getLogger("snappea")
def set_wal_pragma(apps, schema_editor):
# even though we're currently on "sqlite only" for the snappea database, we take the forward-looking approach of at
# least having the escape hatch for other DBs:
if not schema_editor.connection.vendor == 'sqlite':
logger.info('\n Migration info: Database vendor: {}'.format(schema_editor.connection.vendor))
logger.info(' Migration info: Skipping set_wal migration')
return
if schema_editor.connection.is_in_memory_db():
logger.info('\n Migration info: Skipping set_wal migration for in-memory database')
return
with schema_editor.connection.cursor() as cursor:
# > The WAL journaling mode uses a write-ahead log instead of a rollback journal to implement transactions
result = cursor.execute("PRAGMA journal_mode=WAL;")
resulting_row = result.fetchone()
if resulting_row != ("wal",):
raise Exception(f"Failed to set WAL journaling mode, sqlite returned: { resulting_row }")
def backwards(apps, schema_editor):
if not schema_editor.connection.vendor.startswith('sqlite'):
logger.info('\n Migration info: Database vendor: {}'.format(schema_editor.connection.vendor))
logger.info(' Migration info: Skipping (backwards) migration for set_wal')
return
if schema_editor.connection.is_in_memory_db():
logger.info('\n Migration info: Skipping (backwards) set_wal migration for in-memory database')
return
# > The DELETE journaling mode is the normal behavior.
schema_editor.execute("PRAGMA journal_mode=DELETE;")
class Migration(migrations.Migration):
atomic = False
dependencies = [
]
operations = [
migrations.RunPython(set_wal_pragma, backwards),
]