Syncing data between devel/live databases in Django
- by T. Stone
With Django's new multi-db functionality in the development version, I've been trying to work on creating a management command that let's me synchronize the data from the live site down to a developer machine for extended testing. (Having actual data, particularly user-entered data, allows me to test a broader range of inputs.)
Right now I've got a "mostly" working command. It can sync "simple" model data but the problem I'm having is that it ignores ManyToMany fields which I don't see any reason for it do so. Anyone have any ideas of either how to fix that or a better want to handle this? Should I be exporting that first query to a fixture first and then re-importing it?
from django.core.management.base import LabelCommand
from django.db.utils import IntegrityError
from django.db import models
from django.conf import settings
LIVE_DATABASE_KEY = 'live'
class Command(LabelCommand):
help = ("Synchronizes the data between the local machine and the live server")
args = "APP_NAME"
label = 'application name'
requires_model_validation = False
can_import_settings = True
def handle_label(self, label, **options):
# Make sure we're running the command on a developer machine and that we've got the right settings
db_settings = getattr(settings, 'DATABASES', {})
if not LIVE_DATABASE_KEY in db_settings:
print 'Could not find "%s" in database settings.' % LIVE_DATABASE_KEY
return
if db_settings.get('default') == db_settings.get(LIVE_DATABASE_KEY):
print 'Data cannot synchronize with self. This command must be run on a non-production server.'
return
# Fetch all models for the given app
try:
app = models.get_app(label)
app_models = models.get_models(app)
except:
print "The app '%s' could not be found or models could not be loaded for it." % label
for model in app_models:
print 'Syncing %s.%s ...' % (model._meta.app_label, model._meta.object_name)
# Query each model from the live site
qs = model.objects.all().using(LIVE_DATABASE_KEY)
# ...and save it to the local database
for record in qs:
try:
record.save(using='default')
except IntegrityError:
# Skip as the record probably already exists
pass
