Migrate InvenTreeTree to using MPTT model

InvenTree/InvenTree/models.py

@@ -11,10 +11,12 @@ from rest_framework.exceptions import ValidationError
 from django.db.models.signals import pre_delete
 from django.dispatch import receiver
 
+from mptt.models import MPTTModel, TreeForeignKey
+
 from .validators import validate_tree_name
 
 
-class InvenTreeTree(models.Model):
+class InvenTreeTree(MPTTModel):
     """ Provides an abstracted self-referencing tree model for data categories.
 
     - Each Category has one parent Category, which can be blank (for a top-level Category).
@@ -30,6 +32,9 @@ class InvenTreeTree(models.Model):
         abstract = True
         unique_together = ('name', 'parent')
 
+    class MPTTMeta:
+        order_insertion_by = ['name']
+
     name = models.CharField(
         blank=False,
         max_length=100,

InvenTree/part/migrations/0019_auto_20190908_0404.py

@@ -0,0 +1,37 @@
+# Generated by Django 2.2.5 on 2019-09-08 04:04
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('part', '0018_auto_20190907_0941'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='partcategory',
+            name='level',
+            field=models.PositiveIntegerField(default=0, editable=False),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='partcategory',
+            name='lft',
+            field=models.PositiveIntegerField(default=0, editable=False),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='partcategory',
+            name='rght',
+            field=models.PositiveIntegerField(default=0, editable=False),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='partcategory',
+            name='tree_id',
+            field=models.PositiveIntegerField(db_index=True, default=0, editable=False),
+            preserve_default=False,
+        ),
+    ]

InvenTree/part/migrations/0020_auto_20190908_0404.py

@@ -0,0 +1,21 @@
+# Generated by Django 2.2.5 on 2019-09-08 04:04
+
+from django.db import migrations
+from part import models
+
+
+def update_tree(apps, schema_editor):
+    # Update the PartCategory MPTT model
+
+    models.PartCategory.objects.rebuild()
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('part', '0019_auto_20190908_0404'),
+    ]
+
+    operations = [
+        migrations.RunPython(update_tree)
+    ]

InvenTree/stock/migrations/0011_auto_20190908_0404.py

@@ -0,0 +1,37 @@
+# Generated by Django 2.2.5 on 2019-09-08 04:04
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('stock', '0010_stockitem_build'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='stocklocation',
+            name='level',
+            field=models.PositiveIntegerField(default=0, editable=False),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='stocklocation',
+            name='lft',
+            field=models.PositiveIntegerField(default=0, editable=False),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='stocklocation',
+            name='rght',
+            field=models.PositiveIntegerField(default=0, editable=False),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='stocklocation',
+            name='tree_id',
+            field=models.PositiveIntegerField(db_index=True, default=0, editable=False),
+            preserve_default=False,
+        ),
+    ]

InvenTree/stock/migrations/0012_auto_20190908_0405.py

@@ -0,0 +1,22 @@
+# Generated by Django 2.2.5 on 2019-09-08 04:05
+
+from django.db import migrations
+
+from stock import models
+
+
+def update_tree(apps, schema_editor):
+    # Update the StockLocation MPTT model
+
+    models.StockLocation.objects.rebuild()
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('stock', '0011_auto_20190908_0404'),
+    ]
+
+    operations = [
+        migrations.RunPython(update_tree)
+    ]