[UI] Add "can build" part info (#9798)

* Add proper serializer to PartRequirements API endpoint

* Add API endpoint

* Display "can_build" quantity

* Add simple playwright tests

* Bump API version

* Updated docs

* Fix formatting

* Consolidate field names

- Match field names to the PartSerializer

* Adjust frontend

* Add "can_build" to BuildDetail page

* Tweak BuildDetail

* Hide until load

* serializer fixes

src/backend/InvenTree/InvenTree/api_version.py

@@ -1,12 +1,16 @@
 """InvenTree API version information."""
 
 # InvenTree API version
-INVENTREE_API_VERSION = 349
+INVENTREE_API_VERSION = 350
 
 """Increment this API version number whenever there is a significant change to the API that any clients need to know about."""
 
-
 INVENTREE_API_TEXT = """
+v350 -> 2025-06-17 : https://github.com/inventree/InvenTree/pull/9798
+    - Adds "can_build" field to the part requirements API endpoint
+    - Remove "allocated" and "required" fields from the part requirements API endpoint
+    - Add detailed serializer to the part requirements API endpoint
+
 v349 -> 2025-06-13 : https://github.com/inventree/InvenTree/pull/9574
     - Remove the 'create_child_builds' flag from the BuildOrder creation API endpoint
 

src/backend/InvenTree/part/api.py

@@ -754,38 +754,13 @@ class PartRequirements(RetrieveAPI):
     - Sales Orders
     - Build Orders
     - Total requirements
+    - How many of this part can be assembled with available stock
 
     As this data is somewhat complex to calculate, is it not included in the default API
     """
 
     queryset = Part.objects.all()
-    serializer_class = EmptySerializer
+    serializer_class = part_serializers.PartRequirementsSerializer
-
-    def retrieve(self, request, *args, **kwargs):
-        """Construct a response detailing Part requirements."""
-        part = self.get_object()
-
-        data = {
-            'available_stock': part.available_stock,
-            'on_order': part.on_order,
-            'required_build_order_quantity': part.required_build_order_quantity(),
-            'allocated_build_order_quantity': part.build_order_allocation_count(),
-            'required_sales_order_quantity': part.required_sales_order_quantity(),
-            'allocated_sales_order_quantity': part.sales_order_allocation_count(
-                pending=True
-            ),
-        }
-
-        data['allocated'] = (
-            data['allocated_build_order_quantity']
-            + data['allocated_sales_order_quantity']
-        )
-        data['required'] = (
-            data['required_build_order_quantity']
-            + data['required_sales_order_quantity']
-        )
-
-        return Response(data)
 
 
 class PartPricingDetail(RetrieveUpdateAPI):

src/backend/InvenTree/part/serializers.py

@@ -98,10 +98,6 @@ class CategorySerializer(
         if not path_detail and not isGeneratingSchema():
             self.fields.pop('path', None)
 
-    def get_starred(self, category) -> bool:
-        """Return True if the category is directly "starred" by the current user."""
-        return category in self.context.get('starred_categories', [])
-
     @staticmethod
     def annotate_queryset(queryset):
         """Annotate extra information to the queryset."""
@@ -137,6 +133,10 @@ class CategorySerializer(
 
     starred = serializers.SerializerMethodField()
 
+    def get_starred(self, category) -> bool:
+        """Return True if the category is directly "starred" by the current user."""
+        return category in self.context.get('starred_categories', [])
+
     path = serializers.ListField(
         child=serializers.DictField(),
         source='get_path',
@@ -1223,6 +1223,73 @@ class PartSerializer(
         return self.instance
 
 
+class PartRequirementsSerializer(InvenTree.serializers.InvenTreeModelSerializer):
+    """Serializer for Part requirements."""
+
+    class Meta:
+        """Metaclass options."""
+
+        model = Part
+        fields = [
+            'total_stock',
+            'unallocated_stock',
+            'can_build',
+            'ordering',
+            'building',
+            'scheduled_to_build',
+            'required_for_build_orders',
+            'allocated_to_build_orders',
+            'required_for_sales_orders',
+            'allocated_to_sales_orders',
+        ]
+
+    total_stock = serializers.FloatField(read_only=True, label=_('Total Stock'))
+
+    unallocated_stock = serializers.FloatField(
+        source='available_stock', read_only=True, label=_('Available Stock')
+    )
+
+    can_build = serializers.FloatField(read_only=True, label=_('Can Build'))
+
+    ordering = serializers.FloatField(
+        source='on_order', read_only=True, label=_('On Order')
+    )
+
+    building = serializers.FloatField(
+        read_only=True, label=_('In Production'), source='quantity_in_production'
+    )
+
+    scheduled_to_build = serializers.FloatField(
+        read_only=True, label=_('Scheduled to Build'), source='quantity_being_built'
+    )
+
+    required_for_build_orders = serializers.FloatField(
+        source='required_build_order_quantity',
+        read_only=True,
+        label=_('Required for Build Orders'),
+    )
+
+    allocated_to_build_orders = serializers.FloatField(
+        read_only=True,
+        label=_('Allocated to Build Orders'),
+        source='build_order_allocation_count',
+    )
+
+    required_for_sales_orders = serializers.FloatField(
+        source='required_sales_order_quantity',
+        read_only=True,
+        label=_('Required for Sales Orders'),
+    )
+
+    allocated_to_sales_orders = serializers.SerializerMethodField(
+        read_only=True, label=_('Allocated to Sales Orders')
+    )
+
+    def get_allocated_to_sales_orders(self, part) -> float:
+        """Return the allocated sales order quantity."""
+        return part.sales_order_allocation_count(pending=True)
+
+
 class PartStocktakeSerializer(InvenTree.serializers.InvenTreeModelSerializer):
     """Serializer for the PartStocktake model."""
 

src/backend/InvenTree/part/test_api.py

@@ -1843,6 +1843,30 @@ class PartDetailTests(PartImageTestMixin, PartAPITestBase):
         self.assertIn('category_path', response.data)
         self.assertEqual(len(response.data['category_path']), 2)
 
+    def test_part_requirements(self):
+        """Unit test for the "PartRequirements" API endpoint."""
+        url = reverse('api-part-requirements', kwargs={'pk': Part.objects.first().pk})
+
+        # Get the requirements for part 1
+        response = self.get(url, expected_code=200)
+
+        # Check that the response contains the expected fields
+        expected_fields = [
+            'total_stock',
+            'unallocated_stock',
+            'can_build',
+            'ordering',
+            'building',
+            'scheduled_to_build',
+            'required_for_build_orders',
+            'allocated_to_build_orders',
+            'required_for_sales_orders',
+            'allocated_to_sales_orders',
+        ]
+
+        for field in expected_fields:
+            self.assertIn(field, response.data)
+
 
 class PartListTests(PartAPITestBase):
     """Unit tests for the Part List API endpoint."""

src/frontend/lib/enums/ApiEndpoints.tsx

@@ -111,6 +111,7 @@ export enum ApiEndpoints {
   part_parameter_template_list = 'part/parameter/template/',
   part_thumbs_list = 'part/thumbs/',
   part_pricing = 'part/:id/pricing/',
+  part_requirements = 'part/:id/requirements/',
   part_serial_numbers = 'part/:id/serial-numbers/',
   part_scheduling = 'part/:id/scheduling/',
   part_pricing_internal = 'part/internal-price/',

src/frontend/src/pages/build/BuildDetail.tsx

@@ -86,11 +86,24 @@ export default function BuildDetail() {
     refetchOnMount: true
   });
 
+  const { instance: partRequirements, instanceQuery: partRequirementsQuery } =
+    useInstance({
+      endpoint: ApiEndpoints.part_requirements,
+      pk: build?.part,
+      hasPrimaryKey: true,
+      defaultValue: {}
+    });
+
   const detailsPanel = useMemo(() => {
     if (instanceQuery.isFetching) {
       return <Skeleton />;
     }
 
+    const data = {
+      ...build,
+      can_build: partRequirements?.can_build ?? 0
+    };
+
     const tl: DetailsField[] = [
       {
         type: 'link',
@@ -173,10 +186,17 @@ export default function BuildDetail() {
 
     const tr: DetailsField[] = [
       {
-        type: 'text',
+        type: 'number',
         name: 'quantity',
         label: t`Build Quantity`
       },
+      {
+        type: 'number',
+        name: 'can_build',
+        unit: build.part_detail?.units,
+        label: t`Can Build`,
+        hidden: partRequirementsQuery.isFetching
+      },
       {
         type: 'progressbar',
         name: 'completed',
@@ -290,15 +310,20 @@ export default function BuildDetail() {
             pk={build.part}
           />
           <Grid.Col span={{ base: 12, sm: 8 }}>
-            <DetailsTable fields={tl} item={build} />
+            <DetailsTable fields={tl} item={data} />
           </Grid.Col>
         </Grid>
-        <DetailsTable fields={tr} item={build} />
+        <DetailsTable fields={tr} item={data} />
-        <DetailsTable fields={bl} item={build} />
+        <DetailsTable fields={bl} item={data} />
-        <DetailsTable fields={br} item={build} />
+        <DetailsTable fields={br} item={data} />
       </ItemDetailsGrid>
     );
-  }, [build, instanceQuery]);
+  }, [
+    build,
+    instanceQuery,
+    partRequirements,
+    partRequirementsQuery.isFetching
+  ]);
 
   const buildPanels: PanelType[] = useMemo(() => {
     return [

src/frontend/src/pages/part/PartDetail.tsx

@@ -143,6 +143,14 @@ export default function PartDetail() {
     refetchOnMount: true
   });
 
+  const { instance: partRequirements, instanceQuery: partRequirementsQuery } =
+    useInstance({
+      endpoint: ApiEndpoints.part_requirements,
+      pk: id,
+      hasPrimaryKey: true,
+      refetchOnMount: true
+    });
+
   const detailsPanel = useMemo(() => {
     if (instanceQuery.isFetching) {
       return <Skeleton />;
@@ -151,8 +159,23 @@ export default function PartDetail() {
     const data = { ...part };
 
     data.required =
-      (data?.required_for_build_orders ?? 0) +
+      (partRequirements?.required_for_build_orders ??
-      (data?.required_for_sales_orders ?? 0);
+        part?.required_for_build_orders ??
+        0) +
+      (partRequirements?.required_for_sales_orders ??
+        part?.required_for_sales_orders ??
+        0);
+
+    data.allocated =
+      (partRequirements?.allocated_to_build_orders ??
+        part?.allocated_to_build_orders ??
+        0) +
+      (partRequirements?.allocated_to_sales_orders ??
+        part?.allocated_to_sales_orders ??
+        0);
+
+    // Extract requirements data
+    data.can_build = partRequirements?.can_build ?? 0;
 
     // Provide latest serial number info
     if (!!serials.latest) {
@@ -315,13 +338,6 @@ export default function PartDetail() {
           (part.required_for_sales_orders <= 0 &&
             part.allocated_to_sales_orders <= 0)
       },
-      {
-        type: 'number',
-        name: 'can_build',
-        unit: true,
-        label: t`Can Build`,
-        hidden: true // TODO: Expose "can_build" to the API
-      },
       {
         type: 'progressbar',
         name: 'building',
@@ -329,6 +345,13 @@ export default function PartDetail() {
         progress: part.building,
         total: part.scheduled_to_build,
         hidden: !part.assembly || (!part.building && !part.scheduled_to_build)
+      },
+      {
+        type: 'number',
+        name: 'can_build',
+        unit: part.units,
+        label: t`Can Build`,
+        hidden: !part.assembly || partRequirementsQuery.isFetching
       }
     ];
 
@@ -489,7 +512,9 @@ export default function PartDetail() {
     id,
     serials,
     instanceQuery.isFetching,
-    instanceQuery.data
+    instanceQuery.data,
+    partRequirementsQuery.isFetching,
+    partRequirements
   ]);
 
   // Part data panels (recalculate when part data changes)

src/frontend/tests/pages/pui_part.spec.ts

@@ -162,6 +162,26 @@ test('Parts - Locking', async ({ browser }) => {
   await page.getByText('Part parameters cannot be').waitFor();
 });
 
+test('Parts - Details', async ({ browser }) => {
+  const page = await doCachedLogin(browser, { url: 'part/113/details' });
+
+  // Check for expected values on this page
+  await page.getByText('Required for Orders').waitFor();
+  await page.getByText('Allocated to Sales Orders').waitFor();
+  await page.getByText('Can Build').waitFor();
+
+  await page.getByText('0 / 10').waitFor();
+  await page.getByText('4 / 49').waitFor();
+
+  // Badges
+  await page.getByText('Required: 10').waitFor();
+  await page.getByText('No Stock').waitFor();
+  await page.getByText('In Production: 4').waitFor();
+
+  await page.getByText('Creation Date').waitFor();
+  await page.getByText('2022-04-29').waitFor();
+});
+
 test('Parts - Allocations', async ({ browser }) => {
   // Let's look at the allocations for a single stock item
   const page = await doCachedLogin(browser, { url: 'stock/item/324/' });