moviewyrm/bookwyrm/management/commands/deduplicate_book_data.py
2020-12-31 16:30:04 -08:00

83 lines
2.9 KiB
Python

''' PROCEED WITH CAUTION: uses deduplication fields to permanently
merge book data objects '''
from django.core.management.base import BaseCommand
from django.db.models import Count
from bookwyrm import models
def update_related(canonical, obj):
''' update all the models with fk to the object being removed '''
# move related models to canonical
related_models = [
(r.remote_field.name, r.related_model) for r in \
canonical._meta.related_objects]
for (related_field, related_model) in related_models:
related_objs = related_model.objects.filter(
**{related_field: obj})
for related_obj in related_objs:
print(
'replacing in',
related_model.__name__,
related_field,
related_obj.id
)
try:
setattr(related_obj, related_field, canonical)
related_obj.save()
except TypeError:
getattr(related_obj, related_field).add(canonical)
getattr(related_obj, related_field).remove(obj)
def copy_data(canonical, obj):
''' try to get the most data possible '''
for data_field in obj._meta.get_fields():
if not hasattr(data_field, 'activitypub_field'):
continue
data_value = getattr(obj, data_field.name)
if not data_value:
continue
if not getattr(canonical, data_field.name):
print('setting data field', data_field.name, data_value)
setattr(canonical, data_field.name, data_value)
canonical.save()
def dedupe_model(model):
''' combine duplicate editions and update related models '''
fields = model._meta.get_fields()
dedupe_fields = [f for f in fields if \
hasattr(f, 'deduplication_field') and f.deduplication_field]
for field in dedupe_fields:
dupes = model.objects.values(field.name).annotate(
Count(field.name)
).filter(**{'%s__count__gt' % field.name: 1})
for dupe in dupes:
value = dupe[field.name]
if not value or value == '':
continue
print('----------')
print(dupe)
objs = model.objects.filter(
**{field.name: value}
).order_by('id')
canonical = objs.first()
print('keeping', canonical.remote_id)
for obj in objs[1:]:
print(obj.remote_id)
copy_data(canonical, obj)
update_related(canonical, obj)
# remove the outdated entry
obj.delete()
class Command(BaseCommand):
''' dedplucate allllll the book data models '''
help = 'merges duplicate book data'
# pylint: disable=no-self-use,unused-argument
def handle(self, *args, **options):
''' run deudplications '''
dedupe_model(models.Edition)
dedupe_model(models.Work)
dedupe_model(models.Author)