""" Django command similar to 'loaddata' but also deletes.
After 'syncdata' has run, the database will have the same data as the fixture - anything
missing will of been added, anything different will of been updated,
and anything extra will of been deleted.
"""
from django.core.management.base import BaseCommand
from django.core.management.color import no_style
from optparse import make_option
import sys
import os
class Command(BaseCommand):
'syncdata command'
option_list = BaseCommand.option_list + (
make_option('--verbosity', action='store', dest='verbosity', default='1',
type='choice', choices=['0', '1', '2'],
help='Verbosity level; 0=minimal output, 1=normal output, 2=all output'),
)
help = 'Makes the current database have the same data as the fixture(s), no more, no less.'
args = "fixture [fixture ...]"
def remove_objects_not_in(self, objects_to_keep, verbosity):
"""
Deletes all the objects in the database that are not in objects_to_keep.
- objects_to_keep: A map where the keys are classes, and the values are a
set of the objects of that class we should keep.
"""
for class_ in objects_to_keep.keys():
current = class_.objects.all()
current_ids = set( [x.id for x in current] )
keep_ids = set( [x.id for x in objects_to_keep[class_]] )
remove_these_ones = current_ids.difference(keep_ids)
if remove_these_ones:
for obj in current:
if obj.id in remove_these_ones:
obj.delete()
if verbosity >= 2:
print "Deleted object: "+ unicode(obj)
if verbosity > 0 and remove_these_ones:
num_deleted = len(remove_these_ones)
if num_deleted > 1:
type_deleted = unicode(class_._meta.verbose_name_plural)
else:
type_deleted = unicode(class_._meta.verbose_name)
print "Deleted "+ str(num_deleted) +" "+ type_deleted
def handle(self, *fixture_labels, **options):
'Main method of a Django command'
from django.db.models import get_apps
from django.core import serializers
from django.db import connection, transaction
from django.conf import settings
self.style = no_style()
verbosity = int(options.get('verbosity', 1))
show_traceback = options.get('traceback', False)
# Keep a count of the installed objects and fixtures
fixture_count = 0
object_count = 0
objects_per_fixture = []
models = set()
humanize = lambda dirname: dirname and "'%s'" % dirname or 'absolute path'
# Get a cursor (even though we don't need one yet). This has
# the side effect of initializing the test database (if
# it isn't already initialized).
cursor = connection.cursor()
# Start transaction management. All fixtures are installed in a
# single transaction to ensure that all references are resolved.
transaction.commit_unless_managed()
transaction.enter_transaction_management()
transaction.managed(True)
app_fixtures = [os.path.join(os.path.dirname(app.__file__), 'fixtures') \
for app in get_apps()]
for fixture_label in fixture_labels:
parts = fixture_label.split('.')
if len(parts) == 1:
fixture_name = fixture_label
formats = serializers.get_public_serializer_formats()
else:
fixture_name, format = '.'.join(parts[:-1]), parts[-1]
if format in serializers.get_public_serializer_formats():
formats = [format]
else:
formats = []
if formats:
if verbosity > 1:
print "Loading '%s' fixtures..." % fixture_name
else:
sys.stderr.write(
self.style.ERROR("Problem installing fixture '%s': %s is not a known "+ \
"serialization format." % (fixture_name, format))
)
transaction.rollback()
transaction.leave_transaction_management()
return
if os.path.isabs(fixture_name):
fixture_dirs = [fixture_name]
else:
fixture_dirs = app_fixtures + list(settings.FIXTURE_DIRS) + ['']
for fixture_dir in fixture_dirs:
if verbosity > 1:
print "Checking %s for fixtures..." % humanize(fixture_dir)
label_found = False
for format in formats:
serializer = serializers.get_serializer(format)
if verbosity > 1:
print "Trying %s for %s fixture '%s'..." % \
(humanize(fixture_dir), format, fixture_name)
try:
full_path = os.path.join(fixture_dir, '.'.join([fixture_name, format]))
fixture = open(full_path, 'r')
if label_found:
fixture.close()
print self.style.ERROR("Multiple fixtures named '%s' in %s. Aborting." %
(fixture_name, humanize(fixture_dir)))
transaction.rollback()
transaction.leave_transaction_management()
return
else:
fixture_count += 1
objects_per_fixture.append(0)
if verbosity > 0:
print "Installing %s fixture '%s' from %s." % \
(format, fixture_name, humanize(fixture_dir))
try:
objects_to_keep = {}
objects = serializers.deserialize(format, fixture)
for obj in objects:
object_count += 1
objects_per_fixture[-1] += 1
class_ = obj.object.__class__
if not class_ in objects_to_keep:
objects_to_keep[class_] = set()
objects_to_keep[class_].add(obj.object)
models.add(class_)
obj.save()
self.remove_objects_not_in(objects_to_keep, verbosity)
label_found = True
except (SystemExit, KeyboardInterrupt):
raise
except Exception:
import traceback
fixture.close()
transaction.rollback()
transaction.leave_transaction_management()
if show_traceback:
traceback.print_exc()
else:
sys.stderr.write(
self.style.ERROR("Problem installing fixture '%s': %s\n" %
(full_path, traceback.format_exc())))
return
fixture.close()
except:
if verbosity > 1:
print "No %s fixture '%s' in %s." % \
(format, fixture_name, humanize(fixture_dir))
# If any of the fixtures we loaded contain 0 objects, assume that an
# error was encountered during fixture loading.
if 0 in objects_per_fixture:
sys.stderr.write(
self.style.ERROR("No fixture data found for '%s'. (File format may be invalid.)" %
(fixture_name)))
transaction.rollback()
transaction.leave_transaction_management()
return
# If we found even one object in a fixture, we need to reset the
# database sequences.
if object_count > 0:
sequence_sql = connection.ops.sequence_reset_sql(self.style, models)
if sequence_sql:
if verbosity > 1:
print "Resetting sequences"
for line in sequence_sql:
cursor.execute(line)
transaction.commit()
transaction.leave_transaction_management()
if object_count == 0:
if verbosity > 1:
print "No fixtures found."
else:
if verbosity > 0:
print "Installed %d object(s) from %d fixture(s)" % (object_count, fixture_count)
# Close the DB connection. This is required as a workaround for an
# edge case in MySQL: if the same connection is used to
# create tables, load data, and query, the query can return
# incorrect results. See Django #7572, MySQL #37735.
connection.close()