From 40ed2d2e22618dd006fdcca4930352d5be9a4e3c Mon Sep 17 00:00:00 2001
From: Nathan Panchout <nathanpanchout@hotmail.com>
Date: Mon, 17 Mar 2025 14:46:59 +0100
Subject: [PATCH] =?UTF-8?q?=F0=9F=90=9B(back)=20keep=20info=20if=20documen?=
 =?UTF-8?q?t=20has=20deleted=20children?=
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With the soft delete feature, relying on the is_leaf method from the
treebeard is not accurate anymore. To determine if a node is a leaf, it
checks if the number of numchild is equal to 0. But a node can have soft
deleted children, then numchild is equal to 0, but it is not a leaf
because if we want to add a child we have to look for the last child to
compute a correct path. Otherwise we will have an error saying that the
path already exists.
---
 .../0021_remove_document_is_public_and_more.py  | 17 +++++++++++++++++
 src/backend/core/models.py                      | 10 +++++++++-
 2 files changed, 26 insertions(+), 1 deletion(-)
 create mode 100644 src/backend/core/migrations/0021_remove_document_is_public_and_more.py

diff --git a/src/backend/core/migrations/0021_remove_document_is_public_and_more.py b/src/backend/core/migrations/0021_remove_document_is_public_and_more.py
new file mode 100644
index 00000000..97eaa468
--- /dev/null
+++ b/src/backend/core/migrations/0021_remove_document_is_public_and_more.py
@@ -0,0 +1,17 @@
+# Generated by Django 5.1.7 on 2025-03-14 14:03
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("core", "0020_remove_is_public_add_field_attachments_and_duplicated_from"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="document",
+            name="has_deleted_children",
+            field=models.BooleanField(default=False),
+        ),
+    ]
diff --git a/src/backend/core/models.py b/src/backend/core/models.py
index 5c2172fd..d6e79c51 100644
--- a/src/backend/core/models.py
+++ b/src/backend/core/models.py
@@ -384,6 +384,7 @@ class Document(MP_Node, BaseModel):
     )
     deleted_at = models.DateTimeField(null=True, blank=True)
     ancestors_deleted_at = models.DateTimeField(null=True, blank=True)
+    has_deleted_children = models.BooleanField(default=False)
     duplicated_from = models.ForeignKey(
         "self",
         on_delete=models.SET_NULL,
@@ -465,6 +466,12 @@ class Document(MP_Node, BaseModel):
                 content_file = ContentFile(bytes_content)
                 default_storage.save(file_key, content_file)
 
+    def is_leaf(self):
+        """
+        :returns: True if the node is has no children
+        """
+        return not self.has_deleted_children and self.numchild == 0
+
     @property
     def key_base(self):
         """Key base of the location where the document is stored in object storage."""
@@ -886,7 +893,8 @@ class Document(MP_Node, BaseModel):
 
         if self.depth > 1:
             self._meta.model.objects.filter(pk=self.get_parent().pk).update(
-                numchild=models.F("numchild") - 1
+                numchild=models.F("numchild") - 1,
+                has_deleted_children=True,
             )
 
         # Mark all descendants as soft deleted