Add a 'reference_int' field to the models, to be used as a secondary index

InvenTree/build/api.py

@@ -85,7 +85,7 @@ class BuildList(generics.ListCreateAPIView):
     ]
 
     ordering_field_aliases = {
-        'reference': ['integer_ref', 'reference'],
+        'reference': ['reference_int', 'reference'],
     }
 
     search_fields = [

InvenTree/build/migrations/0031_build_reference_int.py

@@ -0,0 +1,18 @@
+# Generated by Django 3.2.5 on 2021-10-14 06:23
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('build', '0030_alter_build_reference'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='build',
+            name='reference_int',
+            field=models.IntegerField(default=0),
+        ),
+    ]

InvenTree/build/models.py

@@ -28,7 +28,7 @@ from mptt.exceptions import InvalidMove
 from InvenTree.status_codes import BuildStatus, StockStatus, StockHistoryCode
 from InvenTree.helpers import increment, getSetting, normalize, MakeBarcode
 from InvenTree.validators import validate_build_order_reference
-from InvenTree.models import InvenTreeAttachment
+from InvenTree.models import InvenTreeAttachment, ReferenceIndexingMixin
 
 import common.models
 
@@ -69,7 +69,7 @@ def get_next_build_number():
     return reference
 
 
-class Build(MPTTModel):
+class Build(MPTTModel, ReferenceIndexingMixin):
     """ A Build object organises the creation of new StockItem objects from other existing StockItem objects.
 
     Attributes:
@@ -108,6 +108,8 @@ class Build(MPTTModel):
 
     def save(self, *args, **kwargs):
 
+        self.rebuild_reference_field()
+
         try:
             super().save(*args, **kwargs)
         except InvalidMove:

InvenTree/build/serializers.py

@@ -10,8 +10,7 @@ from django.core.exceptions import ValidationError as DjangoValidationError
 from django.utils.translation import ugettext_lazy as _
 
 from django.db.models import Case, When, Value
-from django.db.models import BooleanField, IntegerField
-from django.db.models.functions import Cast
+from django.db.models import BooleanField
 
 from rest_framework import serializers
 from rest_framework.serializers import ValidationError
@@ -72,11 +71,6 @@ class BuildSerializer(InvenTreeModelSerializer):
             )
         )
 
-        # Annotate with an "integer" version of the reference field, to be used for natural sorting
-        queryset = queryset.annotate(
-            integer_ref=Cast('reference', output_field=IntegerField())
-        )
-
         return queryset
 
     def __init__(self, *args, **kwargs):