django1/django/core/management/commands/dumpdata.py

175 lines
8.3 KiB
Python

from collections import OrderedDict
from django.apps import apps
from django.core import serializers
from django.core.management.base import BaseCommand, CommandError
from django.db import DEFAULT_DB_ALIAS, router
class Command(BaseCommand):
help = ("Output the contents of the database as a fixture of the given "
"format (using each model's default manager unless --all is "
"specified).")
def add_arguments(self, parser):
parser.add_argument('args', metavar='app_label[.ModelName]', nargs='*',
help='Restricts dumped data to the specified app_label or app_label.ModelName.')
parser.add_argument('--format', default='json', dest='format',
help='Specifies the output serialization format for fixtures.')
parser.add_argument('--indent', default=None, dest='indent', type=int,
help='Specifies the indent level to use when pretty-printing output.')
parser.add_argument('--database', action='store', dest='database',
default=DEFAULT_DB_ALIAS,
help='Nominates a specific database to dump fixtures from. '
'Defaults to the "default" database.')
parser.add_argument('-e', '--exclude', dest='exclude', action='append', default=[],
help='An app_label or app_label.ModelName to exclude '
'(use multiple --exclude to exclude multiple apps/models).')
parser.add_argument('--natural-foreign', action='store_true', dest='use_natural_foreign_keys', default=False,
help='Use natural foreign keys if they are available.')
parser.add_argument('--natural-primary', action='store_true', dest='use_natural_primary_keys', default=False,
help='Use natural primary keys if they are available.')
parser.add_argument('-a', '--all', action='store_true', dest='use_base_manager', default=False,
help="Use Django's base manager to dump all models stored in the database, "
"including those that would otherwise be filtered or modified by a custom manager.")
parser.add_argument('--pks', dest='primary_keys',
help="Only dump objects with given primary keys. "
"Accepts a comma separated list of keys. "
"This option will only work when you specify one model.")
parser.add_argument('-o', '--output', default=None, dest='output',
help='Specifies file to which the output is written.')
def handle(self, *app_labels, **options):
format = options.get('format')
indent = options.get('indent')
using = options.get('database')
excludes = options.get('exclude')
output = options.get('output')
show_traceback = options.get('traceback')
use_natural_foreign_keys = options.get('use_natural_foreign_keys')
use_natural_primary_keys = options.get('use_natural_primary_keys')
use_base_manager = options.get('use_base_manager')
pks = options.get('primary_keys')
if pks:
primary_keys = pks.split(',')
else:
primary_keys = []
excluded_apps = set()
excluded_models = set()
for exclude in excludes:
if '.' in exclude:
try:
model = apps.get_model(exclude)
except LookupError:
raise CommandError('Unknown model in excludes: %s' % exclude)
excluded_models.add(model)
else:
try:
app_config = apps.get_app_config(exclude)
except LookupError as e:
raise CommandError(str(e))
excluded_apps.add(app_config)
if len(app_labels) == 0:
if primary_keys:
raise CommandError("You can only use --pks option with one model")
app_list = OrderedDict((app_config, None)
for app_config in apps.get_app_configs()
if app_config.models_module is not None and app_config not in excluded_apps)
else:
if len(app_labels) > 1 and primary_keys:
raise CommandError("You can only use --pks option with one model")
app_list = OrderedDict()
for label in app_labels:
try:
app_label, model_label = label.split('.')
try:
app_config = apps.get_app_config(app_label)
except LookupError as e:
raise CommandError(str(e))
if app_config.models_module is None or app_config in excluded_apps:
continue
try:
model = app_config.get_model(model_label)
except LookupError:
raise CommandError("Unknown model: %s.%s" % (app_label, model_label))
app_list_value = app_list.setdefault(app_config, [])
# We may have previously seen a "all-models" request for
# this app (no model qualifier was given). In this case
# there is no need adding specific models to the list.
if app_list_value is not None:
if model not in app_list_value:
app_list_value.append(model)
except ValueError:
if primary_keys:
raise CommandError("You can only use --pks option with one model")
# This is just an app - no model qualifier
app_label = label
try:
app_config = apps.get_app_config(app_label)
except LookupError as e:
raise CommandError(str(e))
if app_config.models_module is None or app_config in excluded_apps:
continue
app_list[app_config] = None
# Check that the serialization format exists; this is a shortcut to
# avoid collating all the objects and _then_ failing.
if format not in serializers.get_public_serializer_formats():
try:
serializers.get_serializer(format)
except serializers.SerializerDoesNotExist:
pass
raise CommandError("Unknown serialization format: %s" % format)
def get_objects(count_only=False):
"""
Collate the objects to be serialized. If count_only is True, just
count the number of objects to be serialized.
"""
for model in serializers.sort_dependencies(app_list.items()):
if model in excluded_models:
continue
if not model._meta.proxy and router.allow_migrate_model(using, model):
if use_base_manager:
objects = model._base_manager
else:
objects = model._default_manager
queryset = objects.using(using).order_by(model._meta.pk.name)
if primary_keys:
queryset = queryset.filter(pk__in=primary_keys)
if count_only:
yield queryset.order_by().count()
else:
for obj in queryset.iterator():
yield obj
try:
self.stdout.ending = None
progress_output = None
object_count = 0
# If dumpdata is outputting to stdout, there is no way to display progress
if (output and self.stdout.isatty() and options['verbosity'] > 0):
progress_output = self.stdout
object_count = sum(get_objects(count_only=True))
stream = open(output, 'w') if output else None
try:
serializers.serialize(format, get_objects(), indent=indent,
use_natural_foreign_keys=use_natural_foreign_keys,
use_natural_primary_keys=use_natural_primary_keys,
stream=stream or self.stdout, progress_output=progress_output,
object_count=object_count)
finally:
if stream:
stream.close()
except Exception as e:
if show_traceback:
raise
raise CommandError("Unable to serialize database: %s" % e)