django-softdelete-it
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Add soft-delete functionality to desired models.
django-softdelete-it
Add soft-delete functionality to desired models | with undelete support.
Quick start ############
Follow steps mentioned below to add soft-delete
feature in any model of your django app.
-
pip install django-softdelete-it
-
Add
soft_delete_it
to your INSTALLED_APPS setting like this: ::INSTALLED_APPS = [ ... 'soft_delete_it', ]
-
Import
SoftDeleteModel
from soft_delete_it app to your model file like this: ::from soft_delete_it.models import SoftDeleteModel
-
Inherit
SoftDeleteModel
class to your model class. It will add following features:-
objects
manager's behavior will change such that:-
delete()
method which will soft delete instances - will always return only 'non soft deleted' objects
- ``hard_delete()``` method to hard delete the objects
-
-
all_objects
manager:- will always return both soft deleted and non soft deleted objects
-
hard_delete()
method to hard delete the objects -
only_deleted()
method to return only soft deleted objects -
undelete()
method to un-delete soft-deleted objects
-
Example
::
from django.db import models
from soft_delete_it.models import SoftDeleteModel
class Author(SoftDeleteModel):
name = models.CharField(max_length=50)
dob = models.DateField()
class Article(SoftDeleteModel):
title = models.CharField(max_length=50)
body = models.TextField(null=True)
author = models.ForeignKey(Author, on_delete=models.CASCADE, related_name='articles')
Bob = Author.objects.create(name='bob', dob='2000-12-12')
John = Author.objects.create(name='john', dob='1990-10-12')
Author.objects.all() # return QuerySet with 2 objects
Bob.delete() # Bob is soft-deleted
Author.objects.all() # return QuerySet with 1 object, John
Author.all_objects.all() # return QuerySet with 2 object, Bob and John
Bob.undelete() # un-deletes Bob object
Author.objects.all() # return QuerySet with 2 objects
article1 = Article(title='Bob The Builder', body='')
article1.author = Bob
article1.save()
Article.objects.all() # return QuerySet with 1 object, article1
Bob.delete() # soft-deletes both Bob and article1 as Article's author field is on_delete_cascade and it Inherits SoftDeleteModel
If you are implementing a new Manager
for a model, simply inherit SoftDeleteManager
as well along with other Managers.
If you are implementing a new QuerySet
for a model, you will need to do following:
1. Inherit SoftDeleteQuerySet
2. Write Manager inheriting SoftDeleteManager
which defines soft-delete functionality in it's __init__()
method(as in the example) and override get_queryset()
method(as in the example)
3. Write model class inheriting SoftDeleteModel
and uses above new defined Manager
method(as in the example)
Example with QuerySet
Lets create a QuerySet for Article such that if no author is provided while creating a new article, one default author will be added in object. ::
#Creating a default author object first
default_author = Author.objects.create(name='default')
#Implementing QuerySet
from soft_delete_it.models import SoftDeleteModel, SoftDeleteQuerySet, SoftDeleteManager
class ArticleQuerySet(SoftDeleteQuerySet):
def create(self, **kwargs):
try:
author = kwargs['author']
except KeyError:
kwargs['author'] = Author.objects.get(name='default')
article = super(ArticleQuerySet, self).create(**kwargs)
return article
class ArticleManager(SoftDeleteManager):
def __init__(self, *args, **kwargs):
self.deleted_also = kwargs.get('deleted_also', False)
super(ArticleManager, self).__init__(*args, **kwargs)
def get_queryset(self):
'''return all unsoft-deleted objects'''
if self.deleted_also:
return ArticleQuerySet(self.model)
return ArticleQuerySet(self.model).filter(deleted=None)
class Article(SoftDeleteModel):
title = models.CharField(max_length=50)
body = models.TextField(null=True)
author = models.ForeignKey(Author, on_delete=models.CASCADE, related_name='articles')
objects = ArticleManager.from_queryset(ArticleQuerySet)()
all_objects = ArticleManager.from_queryset(ArticleQuerySet)(deleted_also=True)
How soft-deletion functionality is implemented:
- Create a new soft_delete app, whole code for soft-deletion functionality is implemented in its models.py file.
- Added an abstract
SoftDeleteModel
which contains adeleted
attribute which is aUUIDField
. It will holdNone
for undeleted object and a newuuid4
for deleted objects. - Implemented a
SoftDeleteQuerySet
to override default django'sdelete
method tosoft-delete
objects instead of hard deleting them. -
undelete()
,hard_delete()
,only_deleted()
methods are implemented in same QuerySet class to provide extra features. -
SoftDeleteManger
implemented to use above QuerySet by overridingget_queryset()
method. - QuerySet's delete method is necessary to override to support
bulk_delete
feature. - Call pre_delete and post_delete signals before and after the definition of above delete method.
- Use NestedObjects from django admin utils to soft-delete all related objects.
- Two managers,
objects
andall_objects
to return undeleted, all objects are implemented.