Closes #1846: Enable MPTT for InventoryItem hierarchy

netbox/dcim/migrations/0117_inventoryitem_mptt.py

@@ -0,0 +1,44 @@
+from django.db import migrations, models
+import django.db.models.deletion
+import mptt.fields
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('dcim', '0116_custom_field_data'),
+    ]
+
+    operations = [
+        # The MPTT will be rebuilt in the following migration. Using dummy values for now.
+        migrations.AddField(
+            model_name='inventoryitem',
+            name='level',
+            field=models.PositiveIntegerField(default=0, editable=False),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='inventoryitem',
+            name='lft',
+            field=models.PositiveIntegerField(default=0, editable=False),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='inventoryitem',
+            name='rght',
+            field=models.PositiveIntegerField(default=0, editable=False),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='inventoryitem',
+            name='tree_id',
+            field=models.PositiveIntegerField(db_index=True, default=0, editable=False),
+            preserve_default=False,
+        ),
+        # Convert ForeignKey to TreeForeignKey
+        migrations.AlterField(
+            model_name='inventoryitem',
+            name='parent',
+            field=mptt.fields.TreeForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.CASCADE, related_name='child_items', to='dcim.inventoryitem'),
+        ),
+    ]

netbox/dcim/migrations/0118_inventoryitem_mptt_rebuild.py

@@ -0,0 +1,26 @@
+from django.db import migrations
+import mptt
+import mptt.managers
+
+
+def rebuild_mptt(apps, schema_editor):
+    manager = mptt.managers.TreeManager()
+    InventoryItem = apps.get_model('dcim', 'InventoryItem')
+    manager.model = InventoryItem
+    mptt.register(InventoryItem)
+    manager.contribute_to_class(InventoryItem, 'objects')
+    manager.rebuild()
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('dcim', '0117_inventoryitem_mptt'),
+    ]
+
+    operations = [
+        migrations.RunPython(
+            code=rebuild_mptt,
+            reverse_code=migrations.RunPython.noop
+        ),
+    ]