Repairing dataΒΆ

Python dumps can help in situations where you would need a magician. For example your users accidentally deleted a bunch of data from their database and they don't have a recent backup.

There are situations where you want to be a magician. For example your users accidentally deleted a bunch of data from their database and you don't have a recent backup.

In such situations you can inject data by writing a run script which uses Python dumps.

Here is an example of such a script:

from os.path import join
from django.db.models import Count
from django.core.exceptions import ValidationError

REALLY = False  # set to True when you are sure

p = "20150824a"  # the snapshot from where to restore

# don't execute main(), just load create_aaa_bbb functions
__name__ = ""
execfile(join(p, "restore.py"))

class PartnerLoader:

    def __init__(self):
        self.ignored = 0
        self.restored = 0
        self.errors = 0
        self.pklist = (85229, 84047)

    def flush_deferred_objects(self):
        pass

    def save(self, obj):
        if obj.id in self.pklist:
            if obj.__class__.objects.filter(pk=obj.pk).count() == 0:
                try:
                    obj.full_clean()
                except ValidationError as e:
                    self.errors += 1
                    logger.info("20150826 %s : %s", obj, e)
                    return

                if REALLY: obj.save()
                self.restored += 1
                return
            else:
                self.ignored += 1
                return

    def report(self):
        msg = "Partners: {0} errors, {1} restored, {2} ignored"
        print msg.format(self.errors, self.restored, self.ignored)


class MyLoader:

    def __init__(self):
        self.ignored = 0
        self.restored = 0
        self.errors = 0
        qs = debts_Budget.objects.annotate(num=Count('entry')).filter(num=0)
        self.pklist = qs.values_list('id', flat=True)
        print "Restore entries for", len(self.pklist), "budgets", [int(i) for i in self.pklist]

    def flush_deferred_objects(self):
        pass

    def save(self, obj):
        if obj.budget_id in self.pklist:
            if obj.__class__.objects.filter(pk=obj.pk).count() == 0:
                try:
                    obj.full_clean()
                except ValidationError as e:
                    self.errors += 1
                    print "20150826.py", obj, e
                    return

                if REALLY: obj.save()
                self.restored += 1
                return
            else:
                self.ignored += 1
                return

    def report(self):
        msg = "Entries: {0} errors, {1} restored, {2} ignored"
        print msg.format(self.errors, self.restored, self.ignored)

loader = PartnerLoader()
execfile(join(p, "contacts_partner.py"))
#execfile(join(p, "households_household.py"))
#execfile(join(p, "contacts_company.py"))
#execfile(join(p, "pcsw_client.py"))
loader.report()

loader = MyLoader()
#execfile(join(p, "debts_actor.py"))
#loader.report()
execfile(join(p, "debts_entry.py"))
loader.report()