Refactor existing barcode API endpoints (#5937)

* Refactor existing barcode API endpoints

- Expose fields using proper DRF serializers
- API endpoints are now self documenting
- Validation is handled by serializer models
- Serializers and endpoints are extensible
- Extended existing unit tests

* Catch errors if db not yet loaded

* Tweak unit tests

InvenTree/InvenTree/helpers.py

@@ -349,7 +349,7 @@ def MakeBarcode(cls_name, object_pk: int, object_data=None, **kwargs):
         object_data['id'] = object_pk
         data[cls_name] = object_data
 
-    return json.dumps(data, sort_keys=True)
+    return str(json.dumps(data, sort_keys=True))
 
 
 def GetExportFormats():

InvenTree/InvenTree/helpers_model.py

@@ -228,7 +228,11 @@ def getModelsWithMixin(mixin_class) -> list:
     """
     from django.contrib.contenttypes.models import ContentType
 
-    db_models = [x.model_class() for x in ContentType.objects.all() if x is not None]
+    try:
+        db_models = [x.model_class() for x in ContentType.objects.all() if x is not None]
+    except (OperationalError, ProgrammingError):
+        # Database is likely not yet ready
+        db_models = []
 
     return [x for x in db_models if x is not None and issubclass(x, mixin_class)]
 

InvenTree/order/models.py

@@ -522,7 +522,7 @@ class PurchaseOrder(TotalPriceMixin, Order):
     @property
     def is_pending(self):
         """Return True if the PurchaseOrder is 'pending'"""
-        return self.status == PurchaseOrderStatus.PENDING
+        return self.status == PurchaseOrderStatus.PENDING.value
 
     @property
     def is_open(self):
@@ -536,8 +536,8 @@ class PurchaseOrder(TotalPriceMixin, Order):
         - Status is PENDING
         """
         return self.status in [
-            PurchaseOrderStatus.PLACED,
-            PurchaseOrderStatus.PENDING
+            PurchaseOrderStatus.PLACED.value,
+            PurchaseOrderStatus.PENDING.value
         ]
 
     @transaction.atomic

InvenTree/plugin/base/barcodes/api.py

@@ -7,21 +7,60 @@ from django.utils.translation import gettext_lazy as _
 
 from rest_framework import permissions
 from rest_framework.exceptions import PermissionDenied, ValidationError
+from rest_framework.generics import CreateAPIView
 from rest_framework.response import Response
-from rest_framework.views import APIView
 
 from InvenTree.helpers import hash_barcode
-from order.models import PurchaseOrder
 from plugin import registry
 from plugin.builtin.barcodes.inventree_barcode import \
     InvenTreeInternalBarcodePlugin
-from stock.models import StockLocation
 from users.models import RuleSet
 
+from . import serializers as barcode_serializers
+
 logger = logging.getLogger('inventree')
 
 
-class BarcodeScan(APIView):
+class BarcodeView(CreateAPIView):
+    """Custom view class for handling a barcode scan"""
+
+    # Default serializer class (can be overridden)
+    serializer_class = barcode_serializers.BarcodeSerializer
+
+    def queryset(self):
+        """This API view does not have a queryset"""
+        return None
+
+    # Default permission classes (can be overridden)
+    permission_classes = [
+        permissions.IsAuthenticated,
+    ]
+
+    def create(self, request, *args, **kwargs):
+        """Handle create method - override default create"""
+
+        serializer = self.get_serializer(data=request.data)
+        serializer.is_valid(raise_exception=True)
+        data = serializer.validated_data
+
+        barcode = str(data.pop('barcode')).strip()
+
+        return self.handle_barcode(barcode, request, **data)
+
+    def handle_barcode(self, barcode: str, request, **kwargs):
+        """Handle barcode scan.
+
+        Arguments:
+            barcode: Raw barcode value
+            request: HTTP request object
+
+        kwargs:
+            Any custom fields passed by the specific serializer
+        """
+        raise NotImplementedError(f"handle_barcode not implemented for {self.__class__}")
+
+
+class BarcodeScan(BarcodeView):
     """Endpoint for handling generic barcode scan requests.
 
     Barcode data are decoded by the client application,
@@ -29,47 +68,29 @@ class BarcodeScan(APIView):
 
     A barcode could follow the internal InvenTree barcode format,
     or it could match to a third-party barcode format (e.g. Digikey).
-
-    When a barcode is sent to the server, the following parameters must be provided:
-
-    - barcode: The raw barcode data
-
-    plugins:
-    Third-party barcode formats may be supported using 'plugins'
-    (more information to follow)
-
-    hashing:
-    Barcode hashes are calculated using MD5
     """
 
-    permission_classes = [
-        permissions.IsAuthenticated,
-    ]
+    def handle_barcode(self, barcode: str, request, **kwargs):
+        """Perform barcode scan action
 
-    def post(self, request, *args, **kwargs):
-        """Respond to a barcode POST request.
+        Arguments:
+            barcode: Raw barcode value
+            request: HTTP request object
 
-        Check if required info was provided and then run though the plugin steps or try to match up-
+        kwargs:
+            Any custom fields passed by the specific serializer
         """
-        data = request.data
-
-        barcode_data = data.get('barcode', None)
-
-        if not barcode_data:
-            raise ValidationError({'barcode': _('Missing barcode data')})
 
         # Note: the default barcode handlers are loaded (and thus run) first
         plugins = registry.with_mixin('barcode')
 
-        barcode_hash = hash_barcode(barcode_data)
-
         # Look for a barcode plugin which knows how to deal with this barcode
         plugin = None
         response = {}
 
         for current_plugin in plugins:
 
-            result = current_plugin.scan(barcode_data)
+            result = current_plugin.scan(barcode)
 
             if result is None:
                 continue
@@ -86,8 +107,8 @@ class BarcodeScan(APIView):
                 break
 
         response['plugin'] = plugin.name if plugin else None
-        response['barcode_data'] = barcode_data
-        response['barcode_hash'] = barcode_hash
+        response['barcode_data'] = barcode
+        response['barcode_hash'] = hash_barcode(barcode)
 
         # A plugin has not been found!
         if plugin is None:
@@ -99,44 +120,36 @@ class BarcodeScan(APIView):
             return Response(response)
 
 
-class BarcodeAssign(APIView):
+class BarcodeAssign(BarcodeView):
     """Endpoint for assigning a barcode to a stock item.
 
     - This only works if the barcode is not already associated with an object in the database
     - If the barcode does not match an object, then the barcode hash is assigned to the StockItem
     """
 
-    permission_classes = [
-        permissions.IsAuthenticated
-    ]
+    serializer_class = barcode_serializers.BarcodeAssignSerializer
 
-    def post(self, request, *args, **kwargs):
-        """Respond to a barcode assign POST request.
+    def handle_barcode(self, barcode: str, request, **kwargs):
+        """Respond to a barcode assign request.
 
         Checks inputs and assign barcode (hash) to StockItem.
         """
-        data = request.data
-
-        barcode_data = data.get('barcode', None)
-
-        if not barcode_data:
-            raise ValidationError({'barcode': _('Missing barcode data')})
 
         # Here we only check against 'InvenTree' plugins
         plugins = registry.with_mixin('barcode', builtin=True)
 
         # First check if the provided barcode matches an existing database entry
         for plugin in plugins:
-            result = plugin.scan(barcode_data)
+            result = plugin.scan(barcode)
 
             if result is not None:
                 result["error"] = _("Barcode matches existing item")
                 result["plugin"] = plugin.name
-                result["barcode_data"] = barcode_data
+                result["barcode_data"] = barcode
 
                 raise ValidationError(result)
 
-        barcode_hash = hash_barcode(barcode_data)
+        barcode_hash = hash_barcode(barcode)
 
         valid_labels = []
 
@@ -144,39 +157,32 @@ class BarcodeAssign(APIView):
             label = model.barcode_model_type()
             valid_labels.append(label)
 
-            if label in data:
-                try:
-                    instance = model.objects.get(pk=data[label])
+            if instance := kwargs.get(label, None):
 
-                    # Check that the user has the required permission
-                    app_label = model._meta.app_label
-                    model_name = model._meta.model_name
+                # Check that the user has the required permission
+                app_label = model._meta.app_label
+                model_name = model._meta.model_name
 
-                    table = f"{app_label}_{model_name}"
+                table = f"{app_label}_{model_name}"
 
-                    if not RuleSet.check_table_permission(request.user, table, "change"):
-                        raise PermissionDenied({
-                            "error": f"You do not have the required permissions for {table}"
-                        })
-
-                    instance.assign_barcode(
-                        barcode_data=barcode_data,
-                        barcode_hash=barcode_hash,
-                    )
-
-                    return Response({
-                        'success': f"Assigned barcode to {label} instance",
-                        label: {
-                            'pk': instance.pk,
-                        },
-                        "barcode_data": barcode_data,
-                        "barcode_hash": barcode_hash,
+                if not RuleSet.check_table_permission(request.user, table, "change"):
+                    raise PermissionDenied({
+                        "error": f"You do not have the required permissions for {table}"
                     })
 
-                except (ValueError, model.DoesNotExist):
-                    raise ValidationError({
-                        'error': f"No matching {label} instance found in database",
-                    })
+                instance.assign_barcode(
+                    barcode_data=barcode,
+                    barcode_hash=barcode_hash,
+                )
+
+                return Response({
+                    'success': f"Assigned barcode to {label} instance",
+                    label: {
+                        'pk': instance.pk,
+                    },
+                    "barcode_data": barcode,
+                    "barcode_hash": barcode_hash,
+                })
 
         # If we got here, it means that no valid model types were provided
         raise ValidationError({
@@ -184,23 +190,23 @@ class BarcodeAssign(APIView):
         })
 
 
-class BarcodeUnassign(APIView):
+class BarcodeUnassign(BarcodeView):
     """Endpoint for unlinking / unassigning a custom barcode from a database object"""
 
-    permission_classes = [
-        permissions.IsAuthenticated,
-    ]
+    serializer_class = barcode_serializers.BarcodeUnassignSerializer
+
+    def create(self, request, *args, **kwargs):
+        """Respond to a barcode unassign request."""
+
+        serializer = self.get_serializer(data=request.data)
+        serializer.is_valid(raise_exception=True)
+        data = serializer.validated_data
 
-    def post(self, request, *args, **kwargs):
-        """Respond to a barcode unassign POST request"""
-        # The following database models support assignment of third-party barcodes
         supported_models = InvenTreeInternalBarcodePlugin.get_supported_barcode_models()
 
         supported_labels = [model.barcode_model_type() for model in supported_models]
         model_names = ', '.join(supported_labels)
 
-        data = request.data
-
         matched_labels = []
 
         for label in supported_labels:
@@ -219,15 +225,10 @@ class BarcodeUnassign(APIView):
 
         # At this stage, we know that we have received a single valid field
         for model in supported_models:
+
             label = model.barcode_model_type()
 
-            if label in data:
-                try:
-                    instance = model.objects.get(pk=data[label])
-                except (ValueError, model.DoesNotExist):
-                    raise ValidationError({
-                        label: _('No match found for provided value')
-                    })
+            if instance := data.get(label, None):
 
                 # Check that the user has the required permission
                 app_label = model._meta.app_label
@@ -253,7 +254,7 @@ class BarcodeUnassign(APIView):
         })
 
 
-class BarcodePOReceive(APIView):
+class BarcodePOReceive(BarcodeView):
     """Endpoint for handling receiving parts by scanning their barcode.
 
     Barcode data are decoded by the client application,
@@ -269,32 +270,16 @@ class BarcodePOReceive(APIView):
     - location: The destination location for the received item (optional)
     """
 
-    permission_classes = [
-        permissions.IsAuthenticated,
-    ]
+    serializer_class = barcode_serializers.BarcodePOReceiveSerializer
 
-    def post(self, request, *args, **kwargs):
-        """Respond to a barcode POST request."""
+    def handle_barcode(self, barcode: str, request, **kwargs):
+        """Handle a barcode scan for a purchase order item."""
 
-        data = request.data
+        logger.debug("BarcodePOReceive: scanned barcode - '%s'", barcode)
 
-        if not (barcode_data := data.get("barcode")):
-            raise ValidationError({"barcode": _("Missing barcode data")})
-
-        logger.debug("BarcodePOReceive: scanned barcode - '%s'", barcode_data)
-
-        purchase_order = None
-
-        if purchase_order_pk := data.get("purchase_order"):
-            purchase_order = PurchaseOrder.objects.filter(pk=purchase_order_pk).first()
-            if not purchase_order:
-                raise ValidationError({"purchase_order": _("Invalid purchase order")})
-
-        location = None
-        if (location_pk := data.get("location")):
-            location = StockLocation.objects.get(pk=location_pk)
-            if not location:
-                raise ValidationError({"location": _("Invalid stock location")})
+        # Extract optional fields from the dataset
+        purchase_order = kwargs.get('purchase_order', None)
+        location = kwargs.get('location', None)
 
         plugins = registry.with_mixin("barcode")
 
@@ -303,8 +288,10 @@ class BarcodePOReceive(APIView):
         response = {}
 
         internal_barcode_plugin = next(filter(
-            lambda plugin: plugin.name == "InvenTreeBarcode", plugins))
-        if internal_barcode_plugin.scan(barcode_data):
+            lambda plugin: plugin.name == "InvenTreeBarcode", plugins
+        ))
+
+        if internal_barcode_plugin.scan(barcode):
             response["error"] = _("Item has already been received")
             raise ValidationError(response)
 
@@ -314,7 +301,7 @@ class BarcodePOReceive(APIView):
         for current_plugin in plugins:
 
             result = current_plugin.scan_receive_item(
-                barcode_data,
+                barcode,
                 request.user,
                 purchase_order=purchase_order,
                 location=location,
@@ -335,8 +322,8 @@ class BarcodePOReceive(APIView):
                 break
 
         response["plugin"] = plugin.name if plugin else None
-        response["barcode_data"] = barcode_data
-        response["barcode_hash"] = hash_barcode(barcode_data)
+        response["barcode_data"] = barcode
+        response["barcode_hash"] = hash_barcode(barcode)
 
         # A plugin has not been found!
         if plugin is None:

InvenTree/plugin/base/barcodes/serializers.py

@@ -0,0 +1,107 @@
+"""DRF serializers for barcode scanning API"""
+
+from django.core.exceptions import ValidationError
+from django.utils.translation import gettext_lazy as _
+
+from rest_framework import serializers
+
+import order.models
+import stock.models
+from InvenTree.status_codes import PurchaseOrderStatus
+from plugin.builtin.barcodes.inventree_barcode import \
+    InvenTreeInternalBarcodePlugin
+
+
+class BarcodeSerializer(serializers.Serializer):
+    """Generic serializer for receiving barcode data"""
+
+    MAX_BARCODE_LENGTH = 4095
+
+    barcode = serializers.CharField(
+        required=True, help_text=_('Scanned barcode data'),
+        max_length=MAX_BARCODE_LENGTH,
+    )
+
+
+class BarcodeAssignMixin(serializers.Serializer):
+    """Serializer for linking and unlinking barcode to an internal class"""
+
+    def __init__(self, *args, **kwargs):
+        """Generate serializer fields for each supported model type"""
+
+        super().__init__(*args, **kwargs)
+
+        for model in InvenTreeInternalBarcodePlugin.get_supported_barcode_models():
+            self.fields[model.barcode_model_type()] = serializers.PrimaryKeyRelatedField(
+                queryset=model.objects.all(),
+                required=False, allow_null=True,
+                label=model._meta.verbose_name,
+            )
+
+    @staticmethod
+    def get_model_fields():
+        """Return a list of model fields"""
+        fields = [
+            model.barcode_model_type() for model in InvenTreeInternalBarcodePlugin.get_supported_barcode_models()
+        ]
+
+        return fields
+
+
+class BarcodeAssignSerializer(BarcodeAssignMixin, BarcodeSerializer):
+    """Serializer class for linking a barcode to an internal model"""
+
+    class Meta:
+        """Meta class for BarcodeAssignSerializer"""
+
+        fields = [
+            'barcode',
+            *BarcodeAssignMixin.get_model_fields()
+        ]
+
+
+class BarcodeUnassignSerializer(BarcodeAssignMixin):
+    """Serializer class for unlinking a barcode from an internal model"""
+
+    class Meta:
+        """Meta class for BarcodeUnlinkSerializer"""
+
+        fields = BarcodeAssignMixin.get_model_fields()
+
+
+class BarcodePOReceiveSerializer(BarcodeSerializer):
+    """Serializer for receiving items against a purchase order.
+
+    The following additional fields may be specified:
+
+    - purchase_order: PurchaseOrder object to receive items against
+    - location: Location to receive items into
+    """
+
+    purchase_order = serializers.PrimaryKeyRelatedField(
+        queryset=order.models.PurchaseOrder.objects.all(),
+        required=False,
+        help_text=_('PurchaseOrder to receive items against'),
+    )
+
+    def validate_purchase_order(self, order: order.models.PurchaseOrder):
+        """Validate the provided order"""
+
+        if order.status != PurchaseOrderStatus.PLACED.value:
+            raise ValidationError(_("Purchase order has not been placed"))
+
+        return order
+
+    location = serializers.PrimaryKeyRelatedField(
+        queryset=stock.models.StockLocation.objects.all(),
+        required=False,
+        help_text=_('Location to receive items into'),
+    )
+
+    def validate_location(self, location: stock.models.StockLocation):
+        """Validate the provided location"""
+
+        if location.structural:
+            raise ValidationError(_("Cannot select a structural location"))
+
+        return location

InvenTree/plugin/base/barcodes/test_barcode.py

@@ -2,9 +2,8 @@
 
 from django.urls import reverse
 
-from rest_framework import status
-
 from InvenTree.unit_test import InvenTreeAPITestCase
+from part.models import Part
 from stock.models import StockItem
 
 
@@ -24,150 +23,128 @@ class BarcodeAPITest(InvenTreeAPITestCase):
 
         self.scan_url = reverse('api-barcode-scan')
         self.assign_url = reverse('api-barcode-link')
+        self.unassign_url = reverse('api-barcode-unlink')
 
-    def postBarcode(self, url, barcode):
+    def postBarcode(self, url, barcode, expected_code=None):
         """Post barcode and return results."""
-        return self.client.post(url, format='json', data={'barcode': str(barcode)})
+        return self.post(url, format='json', data={'barcode': str(barcode)}, expected_code=expected_code)
 
     def test_invalid(self):
         """Test that invalid requests fail."""
         # test scan url
-        response = self.client.post(self.scan_url, format='json', data={})
-        self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
+        self.post(self.scan_url, format='json', data={}, expected_code=400)
 
         # test wrong assign urls
-        response = self.client.post(self.assign_url, format='json', data={})
-        self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
-
-        response = self.client.post(self.assign_url, format='json', data={'barcode': '123'})
-        self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
-
-        response = self.client.post(self.assign_url, format='json', data={'barcode': '123', 'stockitem': '123'})
-        self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
+        self.post(self.assign_url, format='json', data={}, expected_code=400)
+        self.post(self.assign_url, format='json', data={'barcode': '123'}, expected_code=400)
+        self.post(self.assign_url, format='json', data={'barcode': '123', 'stockitem': '123'}, expected_code=400)
 
     def test_empty(self):
         """Test an empty barcode scan.
 
-        Ensure that all required data is in the respomse.
+        Ensure that all required data is in the response.
         """
-        response = self.postBarcode(self.scan_url, '')
-
-        self.assertEqual(response.status_code, 400)
+        response = self.postBarcode(self.scan_url, '', expected_code=400)
 
         data = response.data
         self.assertIn('barcode', data)
-        self.assertIn('Missing barcode data', str(response.data['barcode']))
+
+        self.assertIn('This field may not be blank', str(response.data['barcode']))
 
     def test_find_part(self):
         """Test that we can lookup a part based on ID."""
-        response = self.client.post(
+
+        part = Part.objects.first()
+
+        response = self.post(
             self.scan_url,
             {
-                'barcode': {
-                    'part': 1,
-                },
+                'barcode': f'{{"part": {part.pk}}}',
             },
-            format='json',
+            expected_code=200
         )
 
-        self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.assertIn('part', response.data)
         self.assertIn('barcode_data', response.data)
-        self.assertEqual(response.data['part']['pk'], 1)
+        self.assertEqual(response.data['part']['pk'], part.pk)
 
     def test_invalid_part(self):
         """Test response for invalid part."""
-        response = self.client.post(
+        response = self.post(
             self.scan_url,
             {
-                'barcode': {
-                    'part': 999999999,
-                }
+                'barcode': '{"part": 999999999}'
             },
-            format='json'
+            expected_code=400
         )
 
-        self.assertEqual(response.status_code, 400)
         self.assertIn('error', response.data)
 
     def test_find_stock_item(self):
         """Test that we can lookup a stock item based on ID."""
-        response = self.client.post(
+
+        item = StockItem.objects.first()
+
+        response = self.post(
             self.scan_url,
             {
-                'barcode': {
-                    'stockitem': 1,
-                }
+                'barcode': item.format_barcode(),
             },
-            format='json',
+            expected_code=200
         )
 
-        self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.assertIn('stockitem', response.data)
         self.assertIn('barcode_data', response.data)
-        self.assertEqual(response.data['stockitem']['pk'], 1)
+        self.assertEqual(response.data['stockitem']['pk'], item.pk)
 
     def test_invalid_item(self):
         """Test response for invalid stock item."""
-        response = self.client.post(
+        response = self.post(
             self.scan_url,
             {
-                'barcode': {
-                    'stockitem': 999999999,
-                }
+                'barcode': '{"stockitem": 999999999}'
             },
-            format='json'
+            expected_code=400
         )
 
-        self.assertEqual(response.status_code, 400)
         self.assertIn('error', response.data)
 
     def test_find_location(self):
         """Test that we can lookup a stock location based on ID."""
-        response = self.client.post(
+        response = self.post(
             self.scan_url,
             {
-                'barcode': {
-                    'stocklocation': 1,
-                },
+                'barcode': '{"stocklocation": 1}',
             },
-            format='json'
+            expected_code=200
         )
 
-        self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.assertIn('stocklocation', response.data)
         self.assertIn('barcode_data', response.data)
         self.assertEqual(response.data['stocklocation']['pk'], 1)
 
     def test_invalid_location(self):
         """Test response for an invalid location."""
-        response = self.client.post(
+        response = self.post(
             self.scan_url,
             {
-                'barcode': {
-                    'stocklocation': 999999999,
-                }
+                'barcode': '{"stocklocation": 999999999}'
             },
-            format='json'
+            expected_code=400
         )
 
-        self.assertEqual(response.status_code, 400)
         self.assertIn('error', response.data)
 
     def test_integer_barcode(self):
         """Test scan of an integer barcode."""
-        response = self.postBarcode(self.scan_url, '123456789')
-
-        self.assertEqual(response.status_code, 400)
+        response = self.postBarcode(self.scan_url, '123456789', expected_code=400)
 
         data = response.data
         self.assertIn('error', data)
 
     def test_array_barcode(self):
         """Test scan of barcode with string encoded array."""
-        response = self.postBarcode(self.scan_url, "['foo', 'bar']")
-
-        self.assertEqual(response.status_code, 400)
+        response = self.postBarcode(self.scan_url, "['foo', 'bar']", expected_code=400)
 
         data = response.data
         self.assertIn('error', data)
@@ -176,11 +153,9 @@ class BarcodeAPITest(InvenTreeAPITestCase):
         """Test that a barcode is generated with a scan."""
         item = StockItem.objects.get(pk=522)
 
-        response = self.postBarcode(self.scan_url, item.format_barcode())
+        response = self.postBarcode(self.scan_url, item.format_barcode(), expected_code=200)
         data = response.data
 
-        self.assertEqual(response.status_code, status.HTTP_200_OK)
-
         self.assertIn('stockitem', data)
 
         pk = data['stockitem']['pk']
@@ -197,37 +172,88 @@ class BarcodeAPITest(InvenTreeAPITestCase):
 
         barcode_data = 'A-TEST-BARCODE-STRING'
 
-        response = self.client.post(
+        response = self.post(
             self.assign_url, format='json',
             data={
                 'barcode': barcode_data,
                 'stockitem': item.pk
-            }
+            },
+            expected_code=200
         )
 
         data = response.data
 
-        self.assertEqual(response.status_code, status.HTTP_200_OK)
-
         self.assertIn('success', data)
 
         result_hash = data['barcode_hash']
 
         # Read the item out from the database again
-        item = StockItem.objects.get(pk=522)
+        item.refresh_from_db()
 
+        self.assertEqual(item.barcode_data, barcode_data)
         self.assertEqual(result_hash, item.barcode_hash)
 
         # Ensure that the same barcode hash cannot be assigned to a different stock item!
-        response = self.client.post(
+        response = self.post(
             self.assign_url, format='json',
             data={
                 'barcode': barcode_data,
                 'stockitem': 521
-            }
+            },
+            expected_code=400
         )
 
-        data = response.data
+        self.assertIn('error', response.data)
+        self.assertNotIn('success', response.data)
 
-        self.assertIn('error', data)
-        self.assertNotIn('success', data)
+        # Check that we can now unassign a barcode
+        response = self.post(
+            self.unassign_url,
+            {
+                'stockitem': item.pk,
+            },
+            expected_code=200
+        )
+
+        item.refresh_from_db()
+        self.assertEqual(item.barcode_data, '')
+
+        # Check that the 'unassign' endpoint fails if the stockitem is invalid
+        response = self.post(
+            self.unassign_url,
+            {
+                'stockitem': 999999999,
+            },
+            expected_code=400
+        )
+
+    def test_unassign_endpoint(self):
+        """Test that the unassign endpoint works as expected"""
+
+        invalid_keys = ['cat', 'dog', 'fish']
+
+        # Invalid key should fail
+        for k in invalid_keys:
+            response = self.post(
+                self.unassign_url,
+                {
+                    k: 123
+                },
+                expected_code=400
+            )
+
+            self.assertIn("Missing data: Provide one of", str(response.data['error']))
+
+        valid_keys = ['build', 'salesorder', 'part']
+
+        # Valid key but invalid pk should fail
+        for k in valid_keys:
+            response = self.post(
+                self.unassign_url,
+                {
+                    k: 999999999
+                },
+                expected_code=400
+            )
+
+            self.assertIn("object does not exist", str(response.data[k]))

InvenTree/plugin/builtin/barcodes/inventree_barcode.py

@@ -63,8 +63,6 @@ class InvenTreeInternalBarcodePlugin(BarcodeMixin, InvenTreePlugin):
 
         Here we are looking for a dict object which contains a reference to a particular InvenTree database object
         """
-        # Create hash from raw barcode data
-        barcode_hash = hash_barcode(barcode_data)
 
         # Attempt to coerce the barcode data into a dict object
         # This is the internal barcode representation that InvenTree uses
@@ -78,9 +76,11 @@ class InvenTreeInternalBarcodePlugin(BarcodeMixin, InvenTreePlugin):
             except json.JSONDecodeError:
                 pass
 
+        supported_models = self.get_supported_barcode_models()
+
         if barcode_dict is not None and type(barcode_dict) is dict:
             # Look for various matches. First good match will be returned
-            for model in self.get_supported_barcode_models():
+            for model in supported_models:
                 label = model.barcode_model_type()
 
                 if label in barcode_dict:
@@ -91,8 +91,11 @@ class InvenTreeInternalBarcodePlugin(BarcodeMixin, InvenTreePlugin):
                     except (ValueError, model.DoesNotExist):
                         pass
 
+        # Create hash from raw barcode data
+        barcode_hash = hash_barcode(barcode_data)
+
         # If no "direct" hits are found, look for assigned third-party barcodes
-        for model in self.get_supported_barcode_models():
+        for model in supported_models:
             label = model.barcode_model_type()
 
             instance = model.lookup_barcode(barcode_hash)

InvenTree/plugin/builtin/barcodes/test_inventree_barcode.py

@@ -80,8 +80,8 @@ class TestInvenTreeBarcode(InvenTreeAPITestCase):
         # Fail with too many fields provided
         response = self.unassign(
             {
-                'stockitem': 'abcde',
-                'part': 'abcde',
+                'stockitem': stock.models.StockItem.objects.first().pk,
+                'part': part.models.Part.objects.first().pk,
             },
             expected_code=400,
         )
@@ -96,17 +96,17 @@ class TestInvenTreeBarcode(InvenTreeAPITestCase):
             expected_code=400,
         )
 
-        self.assertIn('No match found', str(response.data['stockitem']))
+        self.assertIn('Incorrect type', str(response.data['stockitem']))
 
         # Fail with an invalid Part instance
         response = self.unassign(
             {
-                'part': 'invalid',
+                'part': 99999999999,
             },
             expected_code=400,
         )
 
-        self.assertIn('No match found', str(response.data['part']))
+        self.assertIn('object does not exist', str(response.data['part']))
 
     def test_assign_to_stock_item(self):
         """Test that we can assign a unique barcode to a StockItem object"""
@@ -216,7 +216,7 @@ class TestInvenTreeBarcode(InvenTreeAPITestCase):
             expected_code=400,
         )
 
-        self.assertIn('No matching part instance found in database', str(response.data))
+        self.assertIn('object does not exist', str(response.data['part']))
 
         # Test assigning to a valid part (should pass)
         response = self.assign(