Cleanup models

InvenTree/stock/migrations/0073_alter_stockitem_belongs_to.py

@@ -0,0 +1,19 @@
+# Generated by Django 3.2.10 on 2021-12-20 21:49
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('stock', '0072_remove_stockitem_scheduled_for_deletion'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='stockitem',
+            name='belongs_to',
+            field=models.ForeignKey(blank=True, help_text='Is this item installed in another item?', null=True, on_delete=django.db.models.deletion.CASCADE, related_name='installed_parts', to='stock.stockitem', verbose_name='Installed In'),
+        ),
+    ]

InvenTree/stock/migrations/0073_alter_stockitem_parent.py

@@ -1,20 +0,0 @@
-# Generated by Django 3.2.10 on 2021-12-20 13:54
-
-from django.db import migrations
-import django.db.models.deletion
-import mptt.fields
-
-
-class Migration(migrations.Migration):
-
-    dependencies = [
-        ('stock', '0072_remove_stockitem_scheduled_for_deletion'),
-    ]
-
-    operations = [
-        migrations.AlterField(
-            model_name='stockitem',
-            name='parent',
-            field=mptt.fields.TreeForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.SET_NULL, related_name='children', to='stock.stockitem', verbose_name='Parent Stock Item'),
-        ),
-    ]

InvenTree/stock/models.py

@@ -455,10 +455,11 @@ class StockItem(MPTTModel):
 
     uid = models.CharField(blank=True, max_length=128, help_text=("Unique identifier field"))
 
+    # Note: When a StockItem is deleted, a pre_delete signal handles the parent/child relationship
     parent = TreeForeignKey(
         'self',
         verbose_name=_('Parent Stock Item'),
-        on_delete=models.SET_NULL,
+        on_delete=models.DO_NOTHING,
         blank=True, null=True,
         related_name='children'
     )
@@ -477,6 +478,7 @@ class StockItem(MPTTModel):
         help_text=_('Select a matching supplier part for this stock item')
     )
 
+    # Note: When a StockLocation is deleted, stock items are updated via a signal
     location = TreeForeignKey(
         StockLocation, on_delete=models.DO_NOTHING,
         verbose_name=_('Stock Location'),
@@ -492,10 +494,11 @@ class StockItem(MPTTModel):
         help_text=_('Packaging this stock item is stored in')
     )
 
+    # When deleting a stock item with installed items, those installed items are also installed
     belongs_to = models.ForeignKey(
         'self',
         verbose_name=_('Installed In'),
-        on_delete=models.DO_NOTHING,
+        on_delete=models.CASCADE,
         related_name='installed_parts', blank=True, null=True,
         help_text=_('Is this item installed in another item?')
     )
@@ -800,14 +803,14 @@ class StockItem(MPTTModel):
     def can_delete(self):
         """ Can this stock item be deleted? It can NOT be deleted under the following circumstances:
 
-        - Has child StockItems
+        - Has installed stock items
         - Has a serial number and is tracked
         - Is installed inside another StockItem
         - It has been assigned to a SalesOrder
         - It has been assigned to a BuildOrder
         """
 
-        if self.child_count > 0:
+        if self.installed_item_count() > 0:
             return False
 
         if self.part.trackable and self.serial is not None:
@@ -853,20 +856,13 @@ class StockItem(MPTTModel):
 
         return installed
 
-    def installedItemCount(self):
+    def installed_item_count(self):
         """
         Return the number of stock items installed inside this one.
         """
 
         return self.installed_parts.count()
 
-    def hasInstalledItems(self):
-        """
-        Returns true if this stock item has other stock items installed in it.
-        """
-
-        return self.installedItemCount() > 0
-
     @transaction.atomic
     def installStockItem(self, other_item, quantity, user, notes):
         """
@@ -1225,6 +1221,8 @@ class StockItem(MPTTModel):
         location = kwargs.get('location', None)
         notes = kwargs.get('notes', None)
 
+        parent_id = self.parent.pk if self.parent else None
+
         for other in other_items:
             # If the stock item cannot be merged, return
             if not self.can_merge(other, raise_error=raise_error, **kwargs):
@@ -1246,7 +1244,11 @@ class StockItem(MPTTModel):
                 allocation.stock_item = self()
                 allocation.save()
 
-            # Delete the other stock item
+            # Prevent atomicity issues when we are merging our own "parent" part in
+            if parent_id and parent_id == other.pk:
+                self.parent = None
+                self.save()
+
             other.delete()
 
         self.add_tracking_entry(
@@ -1757,7 +1759,8 @@ class StockItem(MPTTModel):
 
 @receiver(pre_delete, sender=StockItem, dispatch_uid='stock_item_pre_delete_log')
 def before_delete_stock_item(sender, instance, using, **kwargs):
-    """ Receives pre_delete signal from StockItem object.
+    """
+    Receives pre_delete signal from StockItem object.
 
     Before a StockItem is deleted, ensure that each child object is updated,
     to point to the new parent item.

InvenTree/stock/templates/stock/item_base.html

@@ -274,14 +274,6 @@
     <div class='alert alert-block alert-warning'>
         {% trans "This stock item is serialized - it has a unique serial number and the quantity cannot be adjusted." %}
     </div>
-    {% elif item.child_count > 0 %}
-    <div class='alert alert-block alert-warning'>
-        {% trans "This stock item cannot be deleted as it has child items" %}
-    </div>
-    {% elif item.delete_on_deplete and item.can_delete %}
-    <div class='alert alert-block alert-warning'>
-        {% trans "This stock item will be automatically deleted when all stock is depleted." %}
-    </div>
     {% endif %}
     
 </div>