duck_django_soft_delete 0.1.4

A Django framework that provides soft delete functionality with automatic query filtering, admin integration, and safe relation prefetching for models using a deleted_at timestamp.

duck-django-soft-delete

Pragmatic soft delete framework for Django.
It provides a safe and transparent way to "delete" records by marking them with a timestamp instead of permanently removing them from the database.

This approach is useful when you need:

• Data recovery after accidental deletions;
• Historical/audit tracking;
• To keep database integrity while still hiding records from normal queries;
• To allow reusing unique keys (with conditional uniqueness).

---

Features

• deleted_at field automatically added to your models;
• Ready-to-use managers:
  • objects → filters out deleted records;
  • everything → returns all records (including deleted);
• soft_delete() and restore() methods;
• Admin integration: filter by deletion status + actions for Soft Delete and Restore;
• Helper build_prefetches() to automatically prefetch only alive related records;
• Supports partial unique constraints in Postgres (unique only among alive records).

---

Installation

pip install duck-django-soft-delete

Add to your project and import:

# settings.py
INSTALLED_APPS = [
  # ...
  "duck_django_soft_delete",
]

---

Concept

Abstract base

from duck_django_soft_delete.table.soft_delete_table import SoftDeleteTable

class MyModel(SoftDeleteTable):
    # your fields...

SoftDeleteTable defines:

• Model time stamp fields: created_at, updated_at
• Soft delete model field: deleted_at
• Django, soft delete and restore model methods: soft_delete() / restore()
• Django prefetch_related method for soft delete build_prefetches(relations: list[str]) -> list[Prefetch|str]
• Load django model as BaseModel Dto: as_dto(include_fks: bool = False, show_deleted: bool = False) -> BaseModel (abstract method — implement in your model)

Managers

• objects → alive only (deleted_at IS NULL)
• everything → all (alive and deleted)

---

Real example

Model with conditional uniqueness (Postgres)

from duck_django_soft_delete.table.soft_delete_table import SoftDeleteTable
from django.db import models
from uuid import uuid4

class Item(SoftDeleteTable):
    uuid = models.UUIDField(primary_key=True, default=uuid4, editable=False)
    name = models.CharField(max_length=255)
    description = models.TextField(blank=True, null=True, default="")
    is_public = models.BooleanField(default=True)
    
    foreign_key_exemple = models.ForeignKey(
		"foreign_key_exemple.ForeignKeyExemple",
		on_delete=models.CASCADE,
		db_column="foreign_key_exemple_id",
		related_name="foreign_key_exemples",
	)
	
	class Meta(SoftDeleteTable.Meta):
		db_table = "items"

Admin

from duck_django_soft_delete.admin.soft_delete_admin import SoftDeleteAdmin
from django.contrib import admin
from item import Item

@admin.register(Item)
class ItemAdmin(SoftDeleteAdmin):
    list_display = (
        "uuid", 
        "name",
        "is_public",
        "created_at", 
        "updated_at", 
        "deleted_at",
    )
    list_filter = [
	    *SoftDeleteAdmin.list_filter, 
	    "is_public", 
	    "foreign_key_exemple",
	    "updated_at",
	]
    search_fields = ("name", "is_public", "foreign_key_exemple__id", )

    # ... your @admin.display helpers

SoftDeleteAdmin provides:

• filter SoftDeletedAtFilter (Not Deleted / Deleted);
• actions “Soft delete selected” and “Restore selected”;
• get_queryset using everything so admin sees all records.

---

Usage

obj = Item.objects.create(name="X")
obj.soft_delete()           # sets deleted_at = now()
obj.restore()               # clears deleted_at
Item.objects.all()      # only alive
Item.everything.all()   # all

Prefetch alive-only relations

If you want to prefetch only alive children when the related model also inherits SoftDeleteTable:

qs = Item.objects.all().prefetch_related(
    *Item.build_prefetches(["foreign_key_exemples", ])
)

• If the relation inherits SoftDeleteTable, prefetch uses its alive manager.
• If it does not, falls back to standard Django prefetch.

---

Best practices

• Postgres: use UniqueConstraint(..., condition=Q(deleted_at__isnull=True)) for uniqueness only on alive records.

	class Meta(SoftDeleteTable.Meta):
		db_table = "items"
		constraints = [
			models.UniqueConstraint(
				fields=["foreign_key_exemple", "name"],
				condition=Q(deleted_at__isnull=True),
				name="unique_item_name_per_foreign_key_exemple_not_deleted",
			)
		]

• Document whether you override Model.delete() to do soft delete by default (this lib does not enforce — you can choose to keep delete() as hard delete).

---

Compatibility

• Django: 4.2+
• Python: 3.10+

---

Admin — details

• Filter: “Soft Delete” → Not Deleted / Deleted
• Actions:
  • Soft delete selected: calls soft_delete() on alive items;
  • Restore selected: calls restore() on deleted items;
• get_queryset uses model.everything.all() so admin shows all records.

Tip: you can remove Django’s default delete_selected action to avoid accidental hard deletes.

---

Tests

See the tests/ folder in this repo (pytest + pytest-django), covering:

• Managers (objects vs everything);
• soft_delete() and restore();
• Partial unique (Postgres);
• Admin actions;
• build_prefetches().

---

License

MIT