166 lines
7.4 KiB
Python
166 lines
7.4 KiB
Python
from django.core.exceptions import ImproperlyConfigured
|
|
from django.core.management.base import BaseCommand, CommandError
|
|
from django.core import serializers
|
|
from django.db import connections, router, DEFAULT_DB_ALIAS
|
|
from django.utils.datastructures import SortedDict
|
|
|
|
from optparse import make_option
|
|
|
|
class Command(BaseCommand):
|
|
option_list = BaseCommand.option_list + (
|
|
make_option('--format', default='json', dest='format',
|
|
help='Specifies the output serialization format for fixtures.'),
|
|
make_option('--indent', default=None, dest='indent', type='int',
|
|
help='Specifies the indent level to use when pretty-printing output'),
|
|
make_option('--database', action='store', dest='database',
|
|
default=DEFAULT_DB_ALIAS, help='Nominates a specific database to load '
|
|
'fixtures into. Defaults to the "default" database.'),
|
|
make_option('-e', '--exclude', dest='exclude',action='append', default=[],
|
|
help='App to exclude (use multiple --exclude to exclude multiple apps).'),
|
|
make_option('-n', '--natural', action='store_true', dest='use_natural_keys', default=False,
|
|
help='Use natural keys if they are available.'),
|
|
)
|
|
help = 'Output the contents of the database as a fixture of the given format.'
|
|
args = '[appname appname.ModelName ...]'
|
|
|
|
def handle(self, *app_labels, **options):
|
|
from django.db.models import get_app, get_apps, get_models, get_model
|
|
|
|
format = options.get('format','json')
|
|
indent = options.get('indent',None)
|
|
using = options.get('database', DEFAULT_DB_ALIAS)
|
|
connection = connections[using]
|
|
exclude = options.get('exclude',[])
|
|
show_traceback = options.get('traceback', False)
|
|
use_natural_keys = options.get('use_natural_keys', False)
|
|
|
|
excluded_apps = set(get_app(app_label) for app_label in exclude)
|
|
|
|
if len(app_labels) == 0:
|
|
app_list = SortedDict((app, None) for app in get_apps() if app not in excluded_apps)
|
|
else:
|
|
app_list = SortedDict()
|
|
for label in app_labels:
|
|
try:
|
|
app_label, model_label = label.split('.')
|
|
try:
|
|
app = get_app(app_label)
|
|
except ImproperlyConfigured:
|
|
raise CommandError("Unknown application: %s" % app_label)
|
|
|
|
model = get_model(app_label, model_label)
|
|
if model is None:
|
|
raise CommandError("Unknown model: %s.%s" % (app_label, model_label))
|
|
|
|
if app in app_list.keys():
|
|
if app_list[app] and model not in app_list[app]:
|
|
app_list[app].append(model)
|
|
else:
|
|
app_list[app] = [model]
|
|
except ValueError:
|
|
# This is just an app - no model qualifier
|
|
app_label = label
|
|
try:
|
|
app = get_app(app_label)
|
|
except ImproperlyConfigured:
|
|
raise CommandError("Unknown application: %s" % app_label)
|
|
app_list[app] = 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():
|
|
raise CommandError("Unknown serialization format: %s" % format)
|
|
|
|
try:
|
|
serializers.get_serializer(format)
|
|
except KeyError:
|
|
raise CommandError("Unknown serialization format: %s" % format)
|
|
|
|
# Now collate the objects to be serialized.
|
|
objects = []
|
|
for model in sort_dependencies(app_list.items()):
|
|
if not model._meta.proxy and router.allow_syncdb(using, model):
|
|
objects.extend(model._default_manager.using(using).all())
|
|
|
|
try:
|
|
return serializers.serialize(format, objects, indent=indent,
|
|
use_natural_keys=use_natural_keys)
|
|
except Exception, e:
|
|
if show_traceback:
|
|
raise
|
|
raise CommandError("Unable to serialize database: %s" % e)
|
|
|
|
def sort_dependencies(app_list):
|
|
"""Sort a list of app,modellist pairs into a single list of models.
|
|
|
|
The single list of models is sorted so that any model with a natural key
|
|
is serialized before a normal model, and any model with a natural key
|
|
dependency has it's dependencies serialized first.
|
|
"""
|
|
from django.db.models import get_model, get_models
|
|
# Process the list of models, and get the list of dependencies
|
|
model_dependencies = []
|
|
models = set()
|
|
for app, model_list in app_list:
|
|
if model_list is None:
|
|
model_list = get_models(app)
|
|
|
|
for model in model_list:
|
|
models.add(model)
|
|
# Add any explicitly defined dependencies
|
|
if hasattr(model, 'natural_key'):
|
|
deps = getattr(model.natural_key, 'dependencies', [])
|
|
if deps:
|
|
deps = [get_model(*d.split('.')) for d in deps]
|
|
else:
|
|
deps = []
|
|
|
|
# Now add a dependency for any FK or M2M relation with
|
|
# a model that defines a natural key
|
|
for field in model._meta.fields:
|
|
if hasattr(field.rel, 'to'):
|
|
rel_model = field.rel.to
|
|
if hasattr(rel_model, 'natural_key'):
|
|
deps.append(rel_model)
|
|
for field in model._meta.many_to_many:
|
|
rel_model = field.rel.to
|
|
if hasattr(rel_model, 'natural_key'):
|
|
deps.append(rel_model)
|
|
model_dependencies.append((model, deps))
|
|
|
|
model_dependencies.reverse()
|
|
# Now sort the models to ensure that dependencies are met. This
|
|
# is done by repeatedly iterating over the input list of models.
|
|
# If all the dependencies of a given model are in the final list,
|
|
# that model is promoted to the end of the final list. This process
|
|
# continues until the input list is empty, or we do a full iteration
|
|
# over the input models without promoting a model to the final list.
|
|
# If we do a full iteration without a promotion, that means there are
|
|
# circular dependencies in the list.
|
|
model_list = []
|
|
while model_dependencies:
|
|
skipped = []
|
|
changed = False
|
|
while model_dependencies:
|
|
model, deps = model_dependencies.pop()
|
|
|
|
# If all of the models in the dependency list are either already
|
|
# on the final model list, or not on the original serialization list,
|
|
# then we've found another model with all it's dependencies satisfied.
|
|
found = True
|
|
for candidate in ((d not in models or d in model_list) for d in deps):
|
|
if not candidate:
|
|
found = False
|
|
if found:
|
|
model_list.append(model)
|
|
changed = True
|
|
else:
|
|
skipped.append((model, deps))
|
|
if not changed:
|
|
raise CommandError("Can't resolve dependencies for %s in serialized app list." %
|
|
', '.join('%s.%s' % (model._meta.app_label, model._meta.object_name)
|
|
for model, deps in sorted(skipped, key=lambda obj: obj[0].__name__))
|
|
)
|
|
model_dependencies = skipped
|
|
|
|
return model_list |