[Feature] External build order (#9312)

* Add BuildOrder reference to PurchaseOrderLineItem

* Add setting to enable / disable external build orders

* Fix for supplier part detail

* Update forms

* Filter build list by "external" status

* Add "external" attribute to BuildOrder

* Filter by external build when selecting against purchase order line item

* Add frontend elements

* Prevent creation of build outputs

* Tweak related model field

- Send filters when fetching initial data

* Fix migrations

* Fix some existing typos

* Add build info when receiving line items

* Logic fix

* Bump API version

* Updated relationship

* Add external orders tab for order

* Display table of external purchase orders against a build order

* Fix permissions

* Tweak field definition

* Add unit tests

* Tweak api_version.py

* Playwright testing

* Fix discrepancy in 'building' filter

* Add basic documentation

( more work required )

* Tweak docs macros

* Migration fix

* Adjust build page tabs

* Fix imports

* Fix broken import

* Update playywright tests

* Bump API version

* Handle DB issues

* Improve filter

* Cleaner code

* Fix column ordering bug

* Add filters to build output table

* Documentation

* Tweak unit test

* Add "scheduled_for_production" field

* Add helper function to part model

* Cleanup

src/backend/InvenTree/InvenTree/api_version.py

@@ -1,12 +1,15 @@
 """InvenTree API version information."""
 
 # InvenTree API version
-INVENTREE_API_VERSION = 347
+INVENTREE_API_VERSION = 348
 
 """Increment this API version number whenever there is a significant change to the API that any clients need to know about."""
 
 
 INVENTREE_API_TEXT = """
+v348 -> 2025-04-22 : https://github.com/inventree/InvenTree/pull/9312
+    - Adds "external" flag for BuildOrder
+    - Adds link between PurchaseOrderLineItem and BuildOrder
 
 v347 -> 2025-06-12 : https://github.com/inventree/InvenTree/pull/9764
     - Adds "copy_tests" field to the DuplicatePart API endpoint

src/backend/InvenTree/build/api.py

@@ -33,7 +33,7 @@ class BuildFilter(rest_filters.FilterSet):
         """Metaclass options."""
 
         model = Build
-        fields = ['sales_order']
+        fields = ['sales_order', 'external']
 
     status = rest_filters.NumberFilter(label=_('Order Status'), method='filter_status')
 
@@ -355,6 +355,7 @@ class BuildList(DataExportViewMixin, BuildMixin, ListCreateAPI):
         'project_code',
         'priority',
         'level',
+        'external',
     ]
 
     ordering_field_aliases = {

src/backend/InvenTree/build/migrations/0057_build_external.py

@@ -0,0 +1,22 @@
+# Generated by Django 4.2.20 on 2025-03-13 22:34
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("build", "0056_alter_build_link"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="build",
+            name="external",
+            field=models.BooleanField(
+                default=False,
+                help_text="This build order is fulfilled externally",
+                verbose_name="External Build",
+            ),
+        ),
+    ]

src/backend/InvenTree/build/models.py

@@ -96,6 +96,7 @@ class Build(
         sales_order: References to a SalesOrder object for which this Build is required (e.g. the output of this build will be used to fulfil a sales order)
         take_from: Location to take stock from to make this build (if blank, can take from anywhere)
         status: Build status code
+        external: Set to indicate that this build order is fulfilled externally
         batch: Batch code transferred to build parts (optional)
         creation_date: Date the build was created (auto)
         target_date: Date the build will be overdue
@@ -191,6 +192,13 @@ class Build(
         """Validate the BuildOrder model."""
         super().clean()
 
+        if self.external and not self.part.purchaseable:
+            raise ValidationError({
+                'external': _(
+                    'Build orders can only be externally fulfilled for purchaseable parts'
+                )
+            })
+
         if get_global_setting('BUILDORDER_REQUIRE_RESPONSIBLE'):
             if not self.responsible:
                 raise ValidationError({
@@ -286,6 +294,12 @@ class Build(
         ),
     )
 
+    external = models.BooleanField(
+        default=False,
+        verbose_name=_('External Build'),
+        help_text=_('This build order is fulfilled externally'),
+    )
+
     destination = models.ForeignKey(
         'stock.StockLocation',
         verbose_name=_('Destination Location'),

src/backend/InvenTree/build/serializers.py

@@ -73,6 +73,7 @@ class BuildSerializer(
             'completed',
             'completion_date',
             'destination',
+            'external',
             'parent',
             'part',
             'part_name',

src/backend/InvenTree/build/test_build.py

@@ -9,18 +9,21 @@ from django.core.exceptions import ValidationError
 from django.db.models import Sum
 from django.test import TestCase
 from django.test.utils import override_settings
+from django.urls import reverse
 
 import structlog
 
 import build.tasks
 import common.models
+import company.models
 from build.models import Build, BuildItem, BuildLine, generate_next_build_reference
 from build.status_codes import BuildStatus
 from common.settings import set_global_setting
 from InvenTree import status_codes as status
-from InvenTree.unit_test import findOffloadedEvent
+from InvenTree.unit_test import InvenTreeAPITestCase, findOffloadedEvent
+from order.models import PurchaseOrder, PurchaseOrderLineItem
 from part.models import BomItem, BomItemSubstitute, Part, PartTestTemplate
-from stock.models import StockItem, StockItemTestResult
+from stock.models import StockItem, StockItemTestResult, StockLocation
 from users.models import Owner
 
 logger = structlog.get_logger('inventree')
@@ -809,3 +812,142 @@ class AutoAllocationTests(BuildTestBase):
 
         self.assertEqual(self.line_1.unallocated_quantity(), 0)
         self.assertEqual(self.line_2.unallocated_quantity(), 0)
+
+
+class ExternalBuildTest(InvenTreeAPITestCase):
+    """Unit tests for external build order functionality."""
+
+    def test_validation(self):
+        """Test validation of external build logic."""
+        part = Part.objects.create(
+            name='Test part', description='A test part', purchaseable=False
+        )
+
+        # Create a build order
+        # Cannot create an external build for a non-purchaseable part
+        with self.assertRaises(ValidationError) as err:
+            build = Build.objects.create(
+                part=part, title='Test build order', quantity=10, external=True
+            )
+
+            build.clean()
+
+        self.assertIn(
+            'Build orders can only be externally fulfilled for purchaseable parts',
+            str(err.exception.messages),
+        )
+
+    def test_logic(self):
+        """Test external build logic."""
+        # Create a purchaseable assembly part
+        assembly = Part.objects.create(
+            name='Test assembly',
+            description='A test assembly',
+            purchaseable=True,
+            assembly=True,
+            active=True,
+        )
+
+        # Create a supplier part
+        supplier = company.models.Company.objects.create(
+            name='Test supplier', active=True, is_supplier=True
+        )
+
+        supplier_part = company.models.SupplierPart.objects.create(
+            part=assembly, supplier=supplier, SKU='TEST-123'
+        )
+
+        # Create a build order against the assembly
+        build = Build.objects.create(
+            part=assembly, title='Test build order', quantity=10, external=True
+        )
+
+        # Order some parts
+        po = PurchaseOrder.objects.create(supplier=supplier, reference='PO-9999')
+
+        # Create a line item to fulfil the build order
+        po_line = PurchaseOrderLineItem.objects.create(
+            order=po, part=supplier_part, quantity=10, build_order=build
+        )
+
+        # Validate starting conditions
+        self.assertEqual(build.quantity, 10)
+        self.assertEqual(build.completed, 0)
+        self.assertEqual(build.build_outputs.count(), 0)
+        self.assertEqual(build.consumed_stock.count(), 0)
+
+        # PLACE the order
+        po.place_order()
+
+        location = StockLocation.objects.first()
+
+        # Receive half the items against the purchase order
+        po.receive_line_item(po_line, location, 5, self.user)
+
+        # As the order was incomplete, the build output has been marked as "building"
+        self.assertEqual(build.quantity, 10)
+        self.assertEqual(build.completed, 0)
+        self.assertEqual(build.build_outputs.count(), 1)
+
+        output = build.build_outputs.first()
+        self.assertTrue(output.is_building)
+
+        build.complete_build_output(output, self.user)
+        build.refresh_from_db()
+        self.assertEqual(build.completed, 5)
+
+        output.refresh_from_db()
+        self.assertFalse(output.is_building)
+
+        # Mark the build order as completed
+        build.complete_build(self.user)
+        self.assertEqual(build.status, BuildStatus.COMPLETE)
+
+        # Receive the rest of the line item
+        po.receive_line_item(po_line, location, 5, self.user)
+        po_line.refresh_from_db()
+        self.assertEqual(po_line.received, 10)
+
+        build.refresh_from_db()
+        self.assertEqual(build.completed, 10)
+        self.assertEqual(build.build_outputs.count(), 2)
+
+        # As the build was already completed, output has been marked as "complete" too
+        output = build.build_outputs.order_by('-pk').first()
+        self.assertFalse(output.is_building)
+
+    def test_api_filter(self):
+        """Test that the 'external' API filter works as expected."""
+        self.assignRole('build.view')
+
+        # Create a purchaseable assembly part
+        assembly = Part.objects.create(
+            name='Test assembly',
+            description='A test assembly',
+            purchaseable=True,
+            assembly=True,
+            active=True,
+        )
+
+        # Create some build orders
+        for i in range(5):
+            Build.objects.create(
+                part=assembly,
+                title=f'Test build order {i}',
+                quantity=10,
+                external=i % 2 == 0,
+            )
+
+        url = reverse('api-build-list')
+
+        response = self.get(url)
+
+        self.assertEqual(len(response.data), 5)
+
+        # Filter by 'external'
+        response = self.get(url, {'external': 'true'})
+        self.assertEqual(len(response.data), 3)
+
+        # Filter by 'not external'
+        response = self.get(url, {'external': 'false'})
+        self.assertEqual(len(response.data), 2)

src/backend/InvenTree/common/setting/system.py

@@ -756,6 +756,12 @@ SYSTEM_SETTINGS: dict[str, InvenTreeSettingsKeyType] = {
         'default': False,
         'validator': bool,
     },
+    'BUILDORDER_EXTERNAL_BUILDS': {
+        'name': _('External Build Orders'),
+        'description': _('Enable external build order functionality'),
+        'default': False,
+        'validator': bool,
+    },
     'PREVENT_BUILD_COMPLETION_HAVING_INCOMPLETED_TESTS': {
         'name': _('Block Until Tests Pass'),
         'description': _(

src/backend/InvenTree/order/api.py

@@ -19,6 +19,7 @@ from drf_spectacular.utils import extend_schema_field
 from rest_framework import status
 from rest_framework.response import Response
 
+import build.models
 import common.models
 import common.settings
 import company.models
@@ -324,6 +325,22 @@ class PurchaseOrderFilter(OrderFilter):
         label=_('Completed After'), field_name='complete_date', lookup_expr='gt'
     )
 
+    external_build = rest_filters.ModelChoiceFilter(
+        queryset=build.models.Build.objects.filter(external=True),
+        method='filter_external_build',
+        label=_('External Build Order'),
+    )
+
+    @extend_schema_field(
+        rest_framework.serializers.IntegerField(help_text=_('External Build Order'))
+    )
+    def filter_external_build(self, queryset, name, build):
+        """Filter to only include orders which fill fulfil the provided Build Order.
+
+        To achieve this, we return any order which has a line item which is allocated to the build order.
+        """
+        return queryset.filter(lines__build_order=build).distinct()
+
 
 class PurchaseOrderMixin:
     """Mixin class for PurchaseOrder endpoints."""

src/backend/InvenTree/order/migrations/0111_purchaseorderlineitem_build_order.py

@@ -0,0 +1,29 @@
+# Generated by Django 4.2.20 on 2025-04-11 04:59
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("build", "0057_build_external"),
+        ("order", "0110_salesordershipment_barcode_data_and_more"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="purchaseorderlineitem",
+            name="build_order",
+            field=models.ForeignKey(
+                blank=True,
+                help_text="External Build Order to be fulfilled by this line item",
+                limit_choices_to={"external": True},
+                null=True,
+                on_delete=django.db.models.deletion.SET_NULL,
+                related_name="external_line_items",
+                to="build.build",
+                verbose_name="Build Order",
+            ),
+        ),
+    ]

src/backend/InvenTree/order/models.py

@@ -30,6 +30,7 @@ import order.validators
 import report.mixins
 import stock.models
 import users.models as UserModels
+from build.status_codes import BuildStatus
 from common.currency import currency_code_default
 from common.notifications import InvenTreeNotificationBodies
 from common.settings import get_global_setting
@@ -279,7 +280,7 @@ class Order(
 
     Instances of this class:
 
-    - PuchaseOrder
+    - PurchaseOrder
     - SalesOrder
 
     Attributes:
@@ -558,7 +559,7 @@ class PurchaseOrder(TotalPriceMixin, Order):
 
     @classmethod
     def get_status_class(cls):
-        """Return the PurchasOrderStatus class."""
+        """Return the PurchaseOrderStatus class."""
         return PurchaseOrderStatusGroups
 
     @classmethod
@@ -923,7 +924,7 @@ class PurchaseOrder(TotalPriceMixin, Order):
             status: The StockStatus to assign to the item (default: StockStatus.OK)
 
         Keyword Arguments:
-            barch_code: Optional batch code for the new StockItem
+            batch_code: Optional batch code for the new StockItem
             serials: Optional list of serial numbers to assign to the new StockItem(s)
             notes: Optional notes field for the StockItem
             packaging: Optional packaging field for the StockItem
@@ -1005,20 +1006,61 @@ class PurchaseOrder(TotalPriceMixin, Order):
                 serialize = False
                 serials = [None]
 
+            # Construct dataset for receiving items
+            data = {
+                'part': line.part.part,
+                'supplier_part': line.part,
+                'location': location,
+                'quantity': 1 if serialize else stock_quantity,
+                'purchase_order': self,
+                'status': status,
+                'batch': batch_code,
+                'expiry_date': expiry_date,
+                'packaging': packaging,
+                'purchase_price': unit_purchase_price,
+            }
+
+            if build_order := line.build_order:
+                # Receiving items against an "external" build order
+
+                if not build_order.external:
+                    raise ValidationError(
+                        'Cannot receive items against an internal build order'
+                    )
+
+                if build_order.part != data['part']:
+                    raise ValidationError(
+                        'Cannot receive items against a build order for a different part'
+                    )
+
+                if not location and build_order.destination:
+                    # Override with the build order destination (if not specified)
+                    data['location'] = location = build_order.destination
+
+                if build_order.active:
+                    # An 'active' build order marks the items as "in production"
+                    data['build'] = build_order
+                    data['is_building'] = True
+                elif build_order.status == BuildStatus.COMPLETE:
+                    # A 'completed' build order marks the items as "completed"
+                    data['build'] = build_order
+                    data['is_building'] = False
+
+                    # Increase the 'completed' quantity for the build order
+                    build_order.completed += stock_quantity
+                    build_order.save()
+
+                elif build_order.status == BuildStatus.CANCELLED:
+                    # A 'cancelled' build order is ignored
+                    pass
+                else:
+                    # Un-handled state - raise an error
+                    raise ValidationError(
+                        "Cannot receive items against a build order in state '{build_order.status}'"
+                    )
+
             for sn in serials:
-                item = stock.models.StockItem(
-                    part=line.part.part,
-                    supplier_part=line.part,
-                    location=location,
-                    quantity=1 if serialize else stock_quantity,
-                    purchase_order=self,
-                    status=status,
-                    batch=batch_code,
-                    expiry_date=expiry_date,
-                    packaging=packaging,
-                    serial=sn,
-                    purchase_price=unit_purchase_price,
-                )
+                item = stock.models.StockItem(serial=sn, **data)
 
                 # Assign the provided barcode
                 if barcode:
@@ -1639,6 +1681,11 @@ class PurchaseOrderLineItem(OrderLineItem):
 
     Attributes:
         order: Reference to a PurchaseOrder object
+        part: Reference to a SupplierPart object
+        received: Number of items received
+        purchase_price: Unit purchase price for this line item
+        build_order: Link to an external BuildOrder to be fulfilled by this line item
+        destination: Destination for received items
     """
 
     class Meta:
@@ -1670,6 +1717,25 @@ class PurchaseOrderLineItem(OrderLineItem):
             if self.part.supplier != self.order.supplier:
                 raise ValidationError({'part': _('Supplier part must match supplier')})
 
+        if self.build_order:
+            if not self.build_order.external:
+                raise ValidationError({
+                    'build_order': _('Build order must be marked as external')
+                })
+
+            if part := self.part.part:
+                if not part.assembly:
+                    raise ValidationError({
+                        'build_order': _(
+                            'Build orders can only be linked to assembly parts'
+                        )
+                    })
+
+                if self.build_order.part != self.part.part:
+                    raise ValidationError({
+                        'build_order': _('Build order part must match line item part')
+                    })
+
     def __str__(self):
         """Render a string representation of a PurchaseOrderLineItem instance."""
         return '{n} x {part} - {po}'.format(
@@ -1727,6 +1793,17 @@ class PurchaseOrderLineItem(OrderLineItem):
         """Return the 'purchase_price' field as 'price'."""
         return self.purchase_price
 
+    build_order = models.ForeignKey(
+        'build.Build',
+        on_delete=models.SET_NULL,
+        blank=True,
+        related_name='external_line_items',
+        limit_choices_to={'external': True},
+        null=True,
+        verbose_name=_('Build Order'),
+        help_text=_('External Build Order to be fulfilled by this line item'),
+    )
+
     destination = TreeForeignKey(
         'stock.StockLocation',
         on_delete=models.SET_NULL,
@@ -2544,7 +2621,7 @@ class ReturnOrder(TotalPriceMixin, Order):
 
     @transaction.atomic
     def hold_order(self):
-        """Attempt to tranasition to ON_HOLD status."""
+        """Attempt to transition to ON_HOLD status."""
         return self.handle_transition(
             self.status, ReturnOrderStatus.ON_HOLD.value, self, self._action_hold
         )

src/backend/InvenTree/order/serializers.py

@@ -21,6 +21,7 @@ from rest_framework import serializers
 from rest_framework.serializers import ValidationError
 from sql_util.utils import SubqueryCount, SubquerySum
 
+import build.serializers
 import order.models
 import part.filters as part_filters
 import part.models as part_models
@@ -496,6 +497,8 @@ class PurchaseOrderLineItemSerializer(
             'notes',
             'order',
             'order_detail',
+            'build_order',
+            'build_order_detail',
             'overdue',
             'part_detail',
             'supplier_part_detail',
@@ -645,6 +648,10 @@ class PurchaseOrderLineItemSerializer(
         source='order', read_only=True, allow_null=True, many=False
     )
 
+    build_order_detail = build.serializers.BuildSerializer(
+        source='build_order', read_only=True, many=False
+    )
+
     merge_items = serializers.BooleanField(
         label=_('Merge Items'),
         help_text=_(

src/backend/InvenTree/part/filters.py

@@ -44,7 +44,9 @@ from order.status_codes import PurchaseOrderStatusGroups, SalesOrderStatusGroups
 def annotate_in_production_quantity(reference=''):
     """Annotate the 'in production' quantity for each part in a queryset.
 
-    Sum the 'quantity' field for all stock items which are 'in production' for each part.
+    - Sum the 'quantity' field for all stock items which are 'in production' for each part.
+    - This is the total quantity of "incomplete build outputs" for all active builds
+    - This will return the same quantity as the 'quantity_in_production' method on the Part model
 
     Arguments:
         reference: Reference to the part from the current queryset (default = '')
@@ -60,6 +62,28 @@ def annotate_in_production_quantity(reference=''):
     )
 
 
+def annotate_scheduled_to_build_quantity(reference: str = ''):
+    """Annotate the 'scheduled to build' quantity for each part in a queryset.
+
+    - This is total scheduled quantity for all build orders which are 'active'
+    - This may be different to the "in production" quantity
+    - This will return the same quantity as the 'quantity_being_built' method no the Part model
+    """
+    building_filter = Q(status__in=BuildStatusGroups.ACTIVE_CODES)
+
+    return Coalesce(
+        SubquerySum(
+            ExpressionWrapper(
+                F(f'{reference}builds__quantity') - F(f'{reference}builds__completed'),
+                output_field=DecimalField(),
+            ),
+            filter=building_filter,
+        ),
+        Decimal(0),
+        output_field=DecimalField(),
+    )
+
+
 def annotate_on_order_quantity(reference: str = ''):
     """Annotate the 'on order' quantity for each part in a queryset.
 

src/backend/InvenTree/part/models.py

@@ -1627,6 +1627,24 @@ class Part(
 
         return quantity
 
+    @property
+    def quantity_in_production(self):
+        """Quantity of this part currently actively in production.
+
+        Note: This may return a different value to `quantity_being_built`
+        """
+        quantity = 0
+
+        items = self.stock_items.filter(
+            is_building=True, build__status__in=BuildStatusGroups.ACTIVE_CODES
+        )
+
+        for item in items:
+            # The remaining items in the build
+            quantity += item.quantity
+
+        return quantity
+
     def build_order_allocations(self, **kwargs):
         """Return all 'BuildItem' objects which allocate this part to Build objects."""
         include_variants = kwargs.get('include_variants', True)

src/backend/InvenTree/part/serializers.py

@@ -18,7 +18,7 @@ from djmoney.contrib.exchange.exceptions import MissingRate
 from djmoney.contrib.exchange.models import convert_money
 from drf_spectacular.utils import extend_schema_field
 from rest_framework import serializers
-from sql_util.utils import SubqueryCount, SubquerySum
+from sql_util.utils import SubqueryCount
 from taggit.serializers import TagListSerializerField
 
 import common.currency
@@ -33,7 +33,6 @@ import part.stocktake
 import part.tasks
 import stock.models
 import users.models
-from build.status_codes import BuildStatusGroups
 from importer.registry import register_importer
 from InvenTree.mixins import DataImportExportSerializerMixin
 from InvenTree.ready import isGeneratingSchema
@@ -724,6 +723,7 @@ class PartSerializer(
             'allocated_to_build_orders',
             'allocated_to_sales_orders',
             'building',
+            'scheduled_to_build',
             'category_default_location',
             'in_stock',
             'ordering',
@@ -831,16 +831,13 @@ class PartSerializer(
             )
         )
 
-        # Filter to limit builds to "active"
-        build_filter = Q(status__in=BuildStatusGroups.ACTIVE_CODES)
-
         # Annotate with the total 'building' quantity
         queryset = queryset.annotate(
-            building=Coalesce(
-                SubquerySum('builds__quantity', filter=build_filter),
-                Decimal(0),
-                output_field=models.DecimalField(),
-            )
+            building=part_filters.annotate_in_production_quantity()
+        )
+
+        queryset = queryset.annotate(
+            scheduled_to_build=part_filters.annotate_scheduled_to_build_quantity()
         )
 
         # Annotate with the number of 'suppliers'
@@ -947,42 +944,65 @@ class PartSerializer(
     # Annotated fields
     allocated_to_build_orders = serializers.FloatField(read_only=True, allow_null=True)
     allocated_to_sales_orders = serializers.FloatField(read_only=True, allow_null=True)
+
     building = serializers.FloatField(
-        read_only=True, allow_null=True, label=_('Building')
+        read_only=True,
+        allow_null=True,
+        label=_('Building'),
+        help_text=_('Quantity of this part currently being in production'),
     )
+
+    scheduled_to_build = serializers.FloatField(
+        read_only=True,
+        allow_null=True,
+        label=_('Scheduled to Build'),
+        help_text=_('Outstanding quantity of this part scheduled to be built'),
+    )
+
     in_stock = serializers.FloatField(
         read_only=True, allow_null=True, label=_('In Stock')
     )
+
     ordering = serializers.FloatField(
         read_only=True, allow_null=True, label=_('On Order')
     )
+
     required_for_build_orders = serializers.IntegerField(
         read_only=True, allow_null=True
     )
+
     required_for_sales_orders = serializers.IntegerField(
         read_only=True, allow_null=True
     )
+
     stock_item_count = serializers.IntegerField(
         read_only=True, allow_null=True, label=_('Stock Items')
     )
+
     revision_count = serializers.IntegerField(
         read_only=True, allow_null=True, label=_('Revisions')
     )
+
     suppliers = serializers.IntegerField(
         read_only=True, allow_null=True, label=_('Suppliers')
     )
+
     total_in_stock = serializers.FloatField(
         read_only=True, allow_null=True, label=_('Total Stock')
     )
+
     external_stock = serializers.FloatField(
         read_only=True, allow_null=True, label=_('External Stock')
     )
+
     unallocated_stock = serializers.FloatField(
         read_only=True, allow_null=True, label=_('Unallocated Stock')
     )
+
     category_default_location = serializers.IntegerField(
         read_only=True, allow_null=True
     )
+
     variant_stock = serializers.FloatField(
         read_only=True, allow_null=True, label=_('Variant Stock')
     )

src/backend/InvenTree/plugin/base/integration/ScheduleMixin.py

@@ -181,6 +181,7 @@ class ScheduleMixin:
                     obj['args'] = f"'{slug}', '{func_name}'"
 
                 tasks = Schedule.objects.filter(name=task_name)
+
                 if len(tasks) > 1:
                     logger.info(
                         "Found multiple tasks; Adding a new scheduled task '%s'",
@@ -191,10 +192,11 @@ class ScheduleMixin:
                 elif len(tasks) == 1:
                     # Scheduled task already exists - update it!
                     logger.info("Updating scheduled task '%s'", task_name)
-                    instance = Schedule.objects.get(name=task_name)
-                    for item in obj:
-                        setattr(instance, item, obj[item])
-                    instance.save()
+
+                    if instance := tasks.first():
+                        for item in obj:
+                            setattr(instance, item, obj[item])
+                        instance.save()
                 else:
                     logger.info("Adding scheduled task '%s'", task_name)
                     # Create a new scheduled task