from importlib import import_module
from django.apps import apps
from django.core.management.base import BaseCommand, CommandError
from django.core.management.color import no_style
from django.core.management.sql import emit_post_migrate_signal, sql_flush
from django.db import DEFAULT_DB_ALIAS, connections
class Command(BaseCommand):
help = (
'Removes ALL DATA from the database, including data added during '
'migrations. Does not achieve a "fresh install" state.'
)
stealth_options = ('reset_sequences', 'allow_cascade', 'inhibit_post_migrate')
def add_arguments(self, parser):
parser.add_argument(
'--noinput', '--no-input', action='store_false', dest='interactive',
help='Tells Django to NOT prompt the user for input of any kind.',
)
parser.add_argument(
'--database', default=DEFAULT_DB_ALIAS,
help='Nominates a database to flush. Defaults to the "default" database.',
)
def handle(self, **options):
database = options['database']
connection = connections[database]
verbosity = options['verbosity']
interactive = options['interactive']
# The following are stealth options used by Django's internals.
reset_sequences = options.get('reset_sequences', True)
allow_cascade = options.get('allow_cascade', False)
inhibit_post_migrate = options.get('inhibit_post_migrate', False)
self.style = no_style()
# Import the 'management' module within each installed app, to register
# dispatcher events.
for app_config in apps.get_app_configs():
try:
import_module('.management', app_config.name)
except ImportError:
pass
sql_list = sql_flush(self.style, connection,
reset_sequences=reset_sequences,
allow_cascade=allow_cascade)
if interactive:
confirm = input("""You have requested a flush of the database.
This will IRREVERSIBLY DESTROY all data currently in the "%s" database,
and return each table to an empty state.
Are you sure you want to do this?
Type 'yes' to continue, or 'no' to cancel: """ % connection.settings_dict['NAME'])
else:
confirm = 'yes'
if confirm == 'yes':
try:
connection.ops.execute_sql_flush(sql_list)
except Exception as exc:
raise CommandError(
"Database %s couldn't be flushed. Possible reasons:\n"
" * The database isn't running or isn't configured correctly.\n"
" * At least one of the expected database tables doesn't exist.\n"
" * The SQL was invalid.\n"
"Hint: Look at the output of 'django-admin sqlflush'. "
"That's the SQL this command wasn't able to run." % (
connection.settings_dict['NAME'],
)
) from exc
# Empty sql_list may signify an empty database and post_migrate would then crash
if sql_list and not inhibit_post_migrate:
# Emit the post migrate signal. This allows individual applications to
# respond as if the database had been migrated from scratch.
emit_post_migrate_signal(verbosity, interactive, database)
else:
self.stdout.write('Flush cancelled.')