from django.apps import apps
from django.db import DEFAULT_DB_ALIAS, router
from django.utils import six
from django.utils.six.moves import input
def update_contenttypes(app_config, verbosity=2, interactive=True, using=DEFAULT_DB_ALIAS, **kwargs):
"""
Creates content types for models in the given app, removing any model
entries that no longer have a matching model class.
"""
if not app_config.models_module:
return
try:
ContentType = apps.get_model('contenttypes', 'ContentType')
except LookupError:
return
if not router.allow_migrate_model(using, ContentType):
return
ContentType.objects.clear_cache()
app_label = app_config.label
app_models = {
model._meta.model_name: model
for model in app_config.get_models()}
if not app_models:
return
# Get all the content types
content_types = {
ct.model: ct
for ct in ContentType.objects.using(using).filter(app_label=app_label)
}
to_remove = [
ct
for (model_name, ct) in six.iteritems(content_types)
if model_name not in app_models
]
cts = [
ContentType(
app_label=app_label,
model=model_name,
)
for (model_name, model) in six.iteritems(app_models)
if model_name not in content_types
]
ContentType.objects.using(using).bulk_create(cts)
if verbosity >= 2:
for ct in cts:
print("Adding content type '%s | %s'" % (ct.app_label, ct.model))
# Confirm that the content type is stale before deletion.
if to_remove:
if interactive:
content_type_display = '\n'.join(
' %s | %s' % (ct.app_label, ct.model)
for ct in to_remove
)
ok_to_delete = input("""The following content types are stale and need to be deleted:
%s
Any objects related to these content types by a foreign key will also
be deleted. Are you sure you want to delete these content types?
If you're unsure, answer 'no'.
Type 'yes' to continue, or 'no' to cancel: """ % content_type_display)
else:
ok_to_delete = False
if ok_to_delete == 'yes':
for ct in to_remove:
if verbosity >= 2:
print("Deleting stale content type '%s | %s'" % (ct.app_label, ct.model))
ct.delete()
else:
if verbosity >= 2:
print("Stale content types remain.")