Add Metadata to more models (#4898)

* Update models: add MetadataMixin

* Fix name of model in Metadata API definition

* Add API endpoints

* Update API version

* Fix syntax

* Add API endpoint for RO, RO line, RO line extra item

* Add Metadata to Contacts

* Fix link in API version

* Fix name of model

* Fix error?

* Fix error?

* Fix all errors, hopefully..

* Add tests for order, line, extraline metadata

Extend for PO, SO

* Add tests for metadata for Company-related models

* Fix spelling

* Consolidate metadata test for all part models into one test

* Add test for all Stock metadata

* Update stock test_api

* Add all metadata tests for orders

* Fix various errors in tests

* Fix model name

* Add migration files

* Update tests for metadata

* Resolve conflict around API version number

* Rename migration file

* Rename migration file

* Will Contact edit endpoint work better?

* Revert changes in URL definitions

* Remove test, duplicate

* Fix tests with fixed PK, not from fixtures, to use a dynamic PK

* Fix migration overlap

InvenTree/InvenTree/api_version.py

@@ -2,11 +2,15 @@
 
 
 # InvenTree API version
-INVENTREE_API_VERSION = 118
+INVENTREE_API_VERSION = 119
 
 """
 Increment this API version number whenever there is a significant change to the API that any clients need to know about
 
+
+v119 -> 2023-06-01 : https://github.com/inventree/InvenTree/pull/4898
+    - Add Metadata to:  Part test templates, Part parameters, Part category parameter templates, BOM item substitute, Part relateds, Stock item test result
+
 v118 -> 2023-06-01 : https://github.com/inventree/InvenTree/pull/4935
     - Adds extra fields for the PartParameterTemplate model
 

InvenTree/company/api.py

@@ -561,7 +561,10 @@ company_api_urls = [
     ])),
 
     re_path(r'^contact/', include([
-        path('<int:pk>/', ContactDetail.as_view(), name='api-contact-detail'),
+        re_path(r'^(?P<pk>\d+)/?', include([
+            re_path('^metadata/', MetadataView.as_view(), {'model': Contact}, name='api-contact-metadata'),
+            re_path('^.*$', ContactDetail.as_view(), name='api-contact-detail'),
+        ])),
         re_path(r'^.*$', ContactList.as_view(), name='api-contact-list'),
     ])),
 

InvenTree/company/fixtures/contact.yaml

@@ -0,0 +1,9 @@
+# Sample contact data
+- model: company.contact
+  pk: 1
+  fields:
+    name: Johnny Rotten
+    company: 1
+    phone: 001234567
+    email: none@example.com
+    role: Rockstar

InvenTree/company/migrations/0062_contact_metadata.py

@@ -0,0 +1,18 @@
+# Generated by Django 3.2.19 on 2023-05-25 16:06
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('company', '0061_remove_supplierpart_pack_size'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='contact',
+            name='metadata',
+            field=models.JSONField(blank=True, help_text='JSON metadata field, for use by external plugins', null=True, verbose_name='Plugin Metadata'),
+        ),
+    ]

InvenTree/company/models.py

@@ -225,7 +225,7 @@ class CompanyAttachment(InvenTreeAttachment):
     )
 
 
-class Contact(models.Model):
+class Contact(MetadataMixin, models.Model):
     """A Contact represents a person who works at a particular company. A Company may have zero or more associated Contact objects.
 
     Attributes:

InvenTree/company/test_api.py

@@ -6,7 +6,7 @@ from rest_framework import status
 
 from InvenTree.unit_test import InvenTreeAPITestCase
 
-from .models import Company, Contact, SupplierPart
+from .models import Company, Contact, ManufacturerPart, SupplierPart
 
 
 class CompanyTest(InvenTreeAPITestCase):
@@ -233,7 +233,10 @@ class ContactTest(InvenTreeAPITestCase):
     def test_edit(self):
         """Test that we can edit a Contact via the API"""
 
-        url = reverse('api-contact-detail', kwargs={'pk': 1})
+        # Get the first contact
+        contact = Contact.objects.first()
+        # Use this contact in the tests
+        url = reverse('api-contact-detail', kwargs={'pk': contact.pk})
 
         # Retrieve detail view
         data = self.get(url, expected_code=200).data
@@ -259,13 +262,16 @@ class ContactTest(InvenTreeAPITestCase):
             expected_code=200
         )
 
-        contact = Contact.objects.get(pk=1)
+        # Get the contact again
+        contact = Contact.objects.first()
         self.assertEqual(contact.role, 'x')
 
     def test_delete(self):
         """Tests that we can delete a Contact via the API"""
 
-        url = reverse('api-contact-detail', kwargs={'pk': 6})
+        # Get the last contact
+        contact = Contact.objects.first()
+        url = reverse('api-contact-detail', kwargs={'pk': contact.pk})
 
         # Delete (without required permissions)
         self.delete(url, expected_code=403)
@@ -490,3 +496,63 @@ class SupplierPartTest(InvenTreeAPITestCase):
         sp = SupplierPart.objects.get(pk=response.data['pk'])
         self.assertEqual(sp.available, 999)
         self.assertIsNotNone(sp.availability_updated)
+
+
+class CompanyMetadataAPITest(InvenTreeAPITestCase):
+    """Unit tests for the various metadata endpoints of API."""
+
+    fixtures = [
+        'category',
+        'part',
+        'location',
+        'company',
+        'contact',
+        'manufacturer_part',
+        'supplier_part',
+    ]
+
+    roles = [
+        'company.change',
+        'purchase_order.change',
+        'part.change',
+    ]
+
+    def metatester(self, apikey, model):
+        """Generic tester"""
+
+        modeldata = model.objects.first()
+
+        # Useless test unless a model object is found
+        self.assertIsNotNone(modeldata)
+
+        url = reverse(apikey, kwargs={'pk': modeldata.pk})
+
+        # Metadata is initially null
+        self.assertIsNone(modeldata.metadata)
+
+        numstr = f'12{len(apikey)}'
+
+        self.patch(
+            url,
+            {
+                'metadata': {
+                    f'abc-{numstr}': f'xyz-{apikey}-{numstr}',
+                }
+            },
+            expected_code=200
+        )
+
+        # Refresh
+        modeldata.refresh_from_db()
+        self.assertEqual(modeldata.get_metadata(f'abc-{numstr}'), f'xyz-{apikey}-{numstr}')
+
+    def test_metadata(self):
+        """Test all endpoints"""
+
+        for apikey, model in {
+            'api-manufacturer-part-metadata': ManufacturerPart,
+            'api-supplier-part-metadata': SupplierPart,
+            'api-company-metadata': Company,
+            'api-contact-metadata': Contact,
+        }.items():
+            self.metatester(apikey, model)

InvenTree/order/fixtures/return_order.yaml

@@ -51,3 +51,19 @@
     description: 'RMA from a customer'
     customer: 5
     status: 10  # Pending
+
+# 1 x R_4K7_0603
+- model: order.returnorderlineitem
+  pk: 1
+  fields:
+    order: 6
+    item: 1008
+    quantity: 1
+
+# An extra line item
+- model: order.returnorderextraline
+  pk: 1
+  fields:
+    order: 6
+    reference: 'Freight cost'
+    quantity: 1

InvenTree/order/fixtures/sales_order.yaml

@@ -37,3 +37,26 @@
     description: "One sales order, please"
     customer: 5
     status: 60  # Returned
+
+# 1 x R_4K7_0603
+- model: order.salesorderlineitem
+  pk: 1
+  fields:
+    order: 5
+    part: 5
+    quantity: 1
+
+# An extra line item
+- model: order.salesorderextraline
+  pk: 1
+  fields:
+    order: 5
+    reference: 'Freight cost'
+    quantity: 1
+
+# Shipment
+- model: order.salesordershipment
+  pk: 1
+  fields:
+    order: 1
+    reference: "Test Shipment, must be present for metadata test"

InvenTree/order/test_api.py

@@ -509,23 +509,6 @@ class PurchaseOrderTest(OrderTest):
 
         self.assertEqual(po.status, PurchaseOrderStatus.PLACED)
 
-    def test_po_metadata(self):
-        """Test the 'metadata' endpoint for the PurchaseOrder model"""
-        url = reverse('api-po-metadata', kwargs={'pk': 1})
-
-        self.patch(
-            url,
-            {
-                'metadata': {
-                    'yam': 'yum',
-                }
-            },
-            expected_code=200
-        )
-
-        order = models.PurchaseOrder.objects.get(pk=1)
-        self.assertEqual(order.get_metadata('yam'), 'yum')
-
     def test_po_calendar(self):
         """Test the calendar export endpoint"""
 
@@ -1374,23 +1357,6 @@ class SalesOrderTest(OrderTest):
 
         self.assertEqual(so.status, SalesOrderStatus.CANCELLED)
 
-    def test_so_metadata(self):
-        """Test the 'metadata' API endpoint for the SalesOrder model"""
-        url = reverse('api-so-metadata', kwargs={'pk': 1})
-
-        self.patch(
-            url,
-            {
-                'metadata': {
-                    'xyz': 'abc',
-                }
-            },
-            expected_code=200
-        )
-
-        order = models.SalesOrder.objects.get(pk=1)
-        self.assertEqual(order.get_metadata('xyz'), 'abc')
-
     def test_so_calendar(self):
         """Test the calendar export endpoint"""
 
@@ -1887,6 +1853,9 @@ class SalesOrderAllocateTest(OrderTest):
         """Test the SalesOrderShipment list API endpoint"""
         url = reverse('api-so-shipment-list')
 
+        # Count before creation
+        countbefore = models.SalesOrderShipment.objects.count()
+
         # Create some new shipments via the API
         for order in models.SalesOrder.objects.all():
 
@@ -1916,7 +1885,7 @@ class SalesOrderAllocateTest(OrderTest):
         # List *all* shipments
         response = self.get(url, expected_code=200)
 
-        self.assertEqual(len(response.data), 1 + 3 * models.SalesOrder.objects.count())
+        self.assertEqual(len(response.data), countbefore + 3 * models.SalesOrder.objects.count())
 
 
 class ReturnOrderTests(InvenTreeAPITestCase):
@@ -2212,3 +2181,71 @@ class ReturnOrderTests(InvenTreeAPITestCase):
         response = self.get(url, expected_code=200, format=None)
         calendar = Calendar.from_ical(response.content)
         self.assertIsInstance(calendar, Calendar)
+
+
+class OrderMetadataAPITest(InvenTreeAPITestCase):
+    """Unit tests for the various metadata endpoints of API."""
+
+    fixtures = [
+        'category',
+        'part',
+        'company',
+        'location',
+        'supplier_part',
+        'stock',
+        'order',
+        'sales_order',
+        'return_order',
+    ]
+
+    roles = [
+        'purchase_order.change',
+        'sales_order.change',
+        'return_order.change',
+    ]
+
+    def metatester(self, apikey, model):
+        """Generic tester"""
+
+        modeldata = model.objects.first()
+
+        # Useless test unless a model object is found
+        self.assertIsNotNone(modeldata)
+
+        url = reverse(apikey, kwargs={'pk': modeldata.pk})
+
+        # Metadata is initially null
+        self.assertIsNone(modeldata.metadata)
+
+        numstr = f'12{len(apikey)}'
+
+        self.patch(
+            url,
+            {
+                'metadata': {
+                    f'abc-{numstr}': f'xyz-{apikey}-{numstr}',
+                }
+            },
+            expected_code=200
+        )
+
+        # Refresh
+        modeldata.refresh_from_db()
+        self.assertEqual(modeldata.get_metadata(f'abc-{numstr}'), f'xyz-{apikey}-{numstr}')
+
+    def test_metadata(self):
+        """Test all endpoints"""
+
+        for apikey, model in {
+            'api-po-metadata': models.PurchaseOrder,
+            'api-po-line-metadata': models.PurchaseOrderLineItem,
+            'api-po-extra-line-metadata': models.PurchaseOrderExtraLine,
+            'api-so-shipment-metadata': models.SalesOrderShipment,
+            'api-so-metadata': models.SalesOrder,
+            'api-so-line-metadata': models.SalesOrderLineItem,
+            'api-so-extra-line-metadata': models.SalesOrderExtraLine,
+            'api-return-order-metadata': models.ReturnOrder,
+            'api-return-order-line-metadata': models.ReturnOrderLineItem,
+            'api-return-order-extra-line-metadata': models.ReturnOrderExtraLine,
+        }.items():
+            self.metatester(apikey, model)

InvenTree/part/api.py

@@ -1892,7 +1892,10 @@ part_api_urls = [
         re_path(r'^tree/', CategoryTree.as_view(), name='api-part-category-tree'),
 
         re_path(r'^parameters/', include([
-            re_path(r'^(?P<pk>\d+)/', CategoryParameterDetail.as_view(), name='api-part-category-parameter-detail'),
+            re_path(r'^(?P<pk>\d+)/', include([
+                re_path(r'^metadata/', MetadataView.as_view(), {'model': PartCategoryParameterTemplate}, name='api-part-category-parameter-metadata'),
+                re_path(r'^.*$', CategoryParameterDetail.as_view(), name='api-part-category-parameter-detail'),
+            ])),
             re_path(r'^.*$', CategoryParameterList.as_view(), name='api-part-category-parameter-list'),
         ])),
 
@@ -1910,7 +1913,10 @@ part_api_urls = [
 
     # Base URL for PartTestTemplate API endpoints
     re_path(r'^test-template/', include([
-        path(r'<int:pk>/', PartTestTemplateDetail.as_view(), name='api-part-test-template-detail'),
+        path(r'<int:pk>/', include([
+            re_path(r'^metadata/', MetadataView.as_view(), {'model': PartTestTemplate}, name='api-part-test-template-metadata'),
+            re_path(r'^.*$', PartTestTemplateDetail.as_view(), name='api-part-test-template-detail'),
+        ])),
         path('', PartTestTemplateList.as_view(), name='api-part-test-template-list'),
     ])),
 
@@ -1934,7 +1940,10 @@ part_api_urls = [
 
     # Base URL for PartRelated API endpoints
     re_path(r'^related/', include([
-        path(r'<int:pk>/', PartRelatedDetail.as_view(), name='api-part-related-detail'),
+        path(r'<int:pk>/', include([
+            re_path(r'^metadata/', MetadataView.as_view(), {'model': PartRelated}, name='api-part-related-metadata'),
+            re_path(r'^.*$', PartRelatedDetail.as_view(), name='api-part-related-detail'),
+        ])),
         re_path(r'^.*$', PartRelatedList.as_view(), name='api-part-related-list'),
     ])),
 
@@ -1948,7 +1957,10 @@ part_api_urls = [
             re_path(r'^.*$', PartParameterTemplateList.as_view(), name='api-part-parameter-template-list'),
         ])),
 
-        path(r'<int:pk>/', PartParameterDetail.as_view(), name='api-part-parameter-detail'),
+        path(r'<int:pk>/', include([
+            re_path(r'^metadata/?', MetadataView.as_view(), {'model': PartParameter}, name='api-part-parameter-metadata'),
+            re_path(r'^.*$', PartParameterDetail.as_view(), name='api-part-parameter-detail'),
+        ])),
         re_path(r'^.*$', PartParameterList.as_view(), name='api-part-parameter-list'),
     ])),
 
@@ -2012,7 +2024,10 @@ bom_api_urls = [
     re_path(r'^substitute/', include([
 
         # Detail view
-        path(r'<int:pk>/', BomItemSubstituteDetail.as_view(), name='api-bom-substitute-detail'),
+        path(r'<int:pk>/', include([
+            re_path(r'^metadata/?', MetadataView.as_view(), {'model': BomItemSubstitute}, name='api-bom-substitute-metadata'),
+            re_path(r'^.*$', BomItemSubstituteDetail.as_view(), name='api-bom-substitute-detail'),
+        ])),
 
         # Catch all
         re_path(r'^.*$', BomItemSubstituteList.as_view(), name='api-bom-substitute-list'),

InvenTree/part/fixtures/bom.yaml

@@ -50,3 +50,9 @@
     part: 101
     sub_part: 100
     quantity: 10
+
+- model: part.bomitemsubstitute
+  pk: 1
+  fields:
+    part: 5
+    bom_item: 6

InvenTree/part/fixtures/part.yaml

@@ -188,3 +188,9 @@
     level: 0
     lft: 0
     rght: 0
+
+- model: part.partrelated
+  pk: 1
+  fields:
+    part_1: 10003
+    part_2: 10004

InvenTree/part/migrations/0112_auto_20230525_1606.py

@@ -0,0 +1,38 @@
+# Generated by Django 3.2.19 on 2023-05-25 16:06
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('part', '0111_auto_20230521_1350'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='bomitemsubstitute',
+            name='metadata',
+            field=models.JSONField(blank=True, help_text='JSON metadata field, for use by external plugins', null=True, verbose_name='Plugin Metadata'),
+        ),
+        migrations.AddField(
+            model_name='partcategoryparametertemplate',
+            name='metadata',
+            field=models.JSONField(blank=True, help_text='JSON metadata field, for use by external plugins', null=True, verbose_name='Plugin Metadata'),
+        ),
+        migrations.AddField(
+            model_name='partparameter',
+            name='metadata',
+            field=models.JSONField(blank=True, help_text='JSON metadata field, for use by external plugins', null=True, verbose_name='Plugin Metadata'),
+        ),
+        migrations.AddField(
+            model_name='partrelated',
+            name='metadata',
+            field=models.JSONField(blank=True, help_text='JSON metadata field, for use by external plugins', null=True, verbose_name='Plugin Metadata'),
+        ),
+        migrations.AddField(
+            model_name='parttesttemplate',
+            name='metadata',
+            field=models.JSONField(blank=True, help_text='JSON metadata field, for use by external plugins', null=True, verbose_name='Plugin Metadata'),
+        ),
+    ]

InvenTree/part/migrations/0113_auto_20230531_1205.py

@@ -6,7 +6,7 @@ from django.db import migrations, models
 class Migration(migrations.Migration):
 
     dependencies = [
-        ('part', '0111_auto_20230521_1350'),
+        ('part', '0112_auto_20230525_1606'),
     ]
 
     operations = [

InvenTree/part/models.py

@@ -3194,7 +3194,7 @@ class PartCategoryStar(models.Model):
     user = models.ForeignKey(User, on_delete=models.CASCADE, verbose_name=_('User'), related_name='starred_categories')
 
 
-class PartTestTemplate(models.Model):
+class PartTestTemplate(MetadataMixin, models.Model):
     """A PartTestTemplate defines a 'template' for a test which is required to be run against a StockItem (an instance of the Part).
 
     The test template applies "recursively" to part variants, allowing tests to be
@@ -3443,7 +3443,7 @@ def post_save_part_parameter_template(sender, instance, created, **kwargs):
             )
 
 
-class PartParameter(models.Model):
+class PartParameter(MetadataMixin, models.Model):
     """A PartParameter is a specific instance of a PartParameterTemplate. It assigns a particular parameter <key:value> pair to a part.
 
     Attributes:
@@ -3559,7 +3559,7 @@ class PartParameter(models.Model):
         return part_parameter
 
 
-class PartCategoryParameterTemplate(models.Model):
+class PartCategoryParameterTemplate(MetadataMixin, models.Model):
     """A PartCategoryParameterTemplate creates a unique relationship between a PartCategory and a PartParameterTemplate.
 
     Multiple PartParameterTemplate instances can be associated to a PartCategory to drive a default list of parameter templates attached to a Part instance upon creation.
@@ -3999,7 +3999,7 @@ def update_pricing_after_delete(sender, instance, **kwargs):
         instance.part.schedule_pricing_update(create=False)
 
 
-class BomItemSubstitute(models.Model):
+class BomItemSubstitute(MetadataMixin, models.Model):
     """A BomItemSubstitute provides a specification for alternative parts, which can be used in a bill of materials.
 
     Attributes:
@@ -4058,7 +4058,7 @@ class BomItemSubstitute(models.Model):
     )
 
 
-class PartRelated(models.Model):
+class PartRelated(MetadataMixin, models.Model):
     """Store and handle related parts (eg. mating connector, crimps, etc.)."""
 
     class Meta:

InvenTree/part/test_api.py

@@ -22,8 +22,9 @@ from InvenTree.status_codes import (BuildStatus, PurchaseOrderStatus,
                                     StockStatus)
 from InvenTree.unit_test import InvenTreeAPITestCase
 from part.models import (BomItem, BomItemSubstitute, Part, PartCategory,
-                         PartCategoryParameterTemplate, PartParameterTemplate,
+                         PartCategoryParameterTemplate, PartParameter,
-                         PartRelated, PartStocktake)
+                         PartParameterTemplate, PartRelated, PartStocktake,
+                         PartTestTemplate)
 from stock.models import StockItem, StockLocation
 
 
@@ -159,26 +160,6 @@ class PartCategoryAPITest(InvenTreeAPITestCase):
         # Annotation should include parts from all sub-categories
         self.assertEqual(response.data['part_count'], 100)
 
-    def test_category_metadata(self):
-        """Test metadata endpoint for the PartCategory."""
-        cat = PartCategory.objects.get(pk=1)
-
-        cat.metadata = {
-            'foo': 'bar',
-            'water': 'melon',
-            'abc': 'xyz',
-        }
-
-        cat.set_metadata('abc', 'ABC')
-
-        response = self.get(reverse('api-part-category-metadata', kwargs={'pk': 1}), expected_code=200)
-
-        metadata = response.data['metadata']
-
-        self.assertEqual(metadata['foo'], 'bar')
-        self.assertEqual(metadata['water'], 'melon')
-        self.assertEqual(metadata['abc'], 'ABC')
-
     def test_category_parameters(self):
         """Test that the PartCategoryParameterTemplate API function work"""
 
@@ -1665,56 +1646,6 @@ class PartDetailTests(PartAPITestBase):
         self.assertEqual(data['in_stock'], 9000)
         self.assertEqual(data['unallocated_stock'], 9000)
 
-    def test_part_metadata(self):
-        """Tests for the part metadata endpoint."""
-        url = reverse('api-part-metadata', kwargs={'pk': 1})
-
-        part = Part.objects.get(pk=1)
-
-        # Metadata is initially null
-        self.assertIsNone(part.metadata)
-
-        part.metadata = {'foo': 'bar'}
-        part.save()
-
-        response = self.get(url, expected_code=200)
-
-        self.assertEqual(response.data['metadata']['foo'], 'bar')
-
-        # Add more data via the API
-        # Using the 'patch' method causes the new data to be merged in
-        self.patch(
-            url,
-            {
-                'metadata': {
-                    'hello': 'world',
-                }
-            },
-            expected_code=200
-        )
-
-        part.refresh_from_db()
-
-        self.assertEqual(part.metadata['foo'], 'bar')
-        self.assertEqual(part.metadata['hello'], 'world')
-
-        # Now, issue a PUT request (existing data will be replacted)
-        self.put(
-            url,
-            {
-                'metadata': {
-                    'x': 'y'
-                },
-            },
-            expected_code=200
-        )
-
-        part.refresh_from_db()
-
-        self.assertFalse('foo' in part.metadata)
-        self.assertFalse('hello' in part.metadata)
-        self.assertEqual(part.metadata['x'], 'y')
-
 
 class PartListTests(PartAPITestBase):
     """Unit tests for the Part List API endpoint"""
@@ -2536,9 +2467,13 @@ class BomItemTest(InvenTreeAPITestCase):
         url = reverse('api-bom-substitute-list')
         stock_url = reverse('api-stock-list')
 
-        # Initially we have no substitute parts
+        # Initially we may have substitute parts
+        # Count first, operate directly on Model
+        countbefore = BomItemSubstitute.objects.count()
+
+        # Now, make sure API returns the same count
         response = self.get(url, expected_code=200)
-        self.assertEqual(len(response.data), 0)
+        self.assertEqual(len(response.data), countbefore)
 
         # BOM item we are interested in
         bom_item = BomItem.objects.get(pk=1)
@@ -2594,9 +2529,9 @@ class BomItemTest(InvenTreeAPITestCase):
 
             self.assertEqual(len(response.data), n_items + ii + 1)
 
-        # There should now be 5 substitute parts available in the database
+        # There should now be 5 more substitute parts available in the database
         response = self.get(url, expected_code=200)
-        self.assertEqual(len(response.data), 5)
+        self.assertEqual(len(response.data), countbefore + 5)
 
         # The BomItem detail endpoint should now also reflect the substitute data
         data = self.get(
@@ -3050,3 +2985,71 @@ class PartStocktakeTest(InvenTreeAPITestCase):
         InvenTreeSetting.set_setting('STOCKTAKE_ENABLE', True, None)
         response = self.post(url, data={}, expected_code=400)
         self.assertIn('Background worker check failed', str(response.data))
+
+
+class PartMetadataAPITest(InvenTreeAPITestCase):
+    """Unit tests for the various metadata endpoints of API."""
+
+    fixtures = [
+        'category',
+        'part',
+        'params',
+        'location',
+        'bom',
+        'company',
+        'test_templates',
+        'manufacturer_part',
+        'supplier_part',
+        'order',
+        'stock',
+    ]
+
+    roles = [
+        'part.change',
+        'part_category.change',
+    ]
+
+    def metatester(self, apikey, model):
+        """Generic tester"""
+
+        modeldata = model.objects.first()
+
+        # Useless test unless a model object is found
+        self.assertIsNotNone(modeldata)
+
+        url = reverse(apikey, kwargs={'pk': modeldata.pk})
+
+        # Metadata is initially null
+        self.assertIsNone(modeldata.metadata)
+
+        numstr = randint(100, 900)
+
+        self.patch(
+            url,
+            {
+                'metadata': {
+                    f'abc-{numstr}': f'xyz-{apikey}-{numstr}',
+                }
+            },
+            expected_code=200
+        )
+
+        # Refresh
+        modeldata.refresh_from_db()
+        self.assertEqual(modeldata.get_metadata(f'abc-{numstr}'), f'xyz-{apikey}-{numstr}')
+
+    def test_metadata(self):
+        """Test all endpoints"""
+
+        for apikey, model in {
+            'api-part-category-parameter-metadata': PartCategoryParameterTemplate,
+            'api-part-category-metadata': PartCategory,
+            'api-part-test-template-metadata': PartTestTemplate,
+            'api-part-related-metadata': PartRelated,
+            'api-part-parameter-template-metadata': PartParameterTemplate,
+            'api-part-parameter-metadata': PartParameter,
+            'api-part-metadata': Part,
+            'api-bom-substitute-metadata': BomItemSubstitute,
+            'api-bom-item-metadata': BomItem,
+        }.items():
+            self.metatester(apikey, model)

InvenTree/part/test_part.py

@@ -294,8 +294,10 @@ class PartTest(TestCase):
         """Unit tests for the PartRelated model"""
 
         # Create a part relationship
+        # Count before creation
+        countbefore = PartRelated.objects.count()
         PartRelated.objects.create(part_1=self.r1, part_2=self.r2)
-        self.assertEqual(PartRelated.objects.count(), 1)
+        self.assertEqual(PartRelated.objects.count(), countbefore + 1)
 
         # Creating a duplicate part relationship should fail
         with self.assertRaises(ValidationError):
@@ -321,7 +323,7 @@ class PartTest(TestCase):
         # Delete a part, ensure the relationship also gets deleted
         self.r1.delete()
 
-        self.assertEqual(PartRelated.objects.count(), 0)
+        self.assertEqual(PartRelated.objects.count(), countbefore)
         self.assertEqual(len(self.r2.get_related_parts()), 0)
 
         # Add multiple part relationships to self.r2
@@ -330,12 +332,12 @@ class PartTest(TestCase):
 
         n = Part.objects.count() - 1
 
-        self.assertEqual(PartRelated.objects.count(), n)
+        self.assertEqual(PartRelated.objects.count(), n + countbefore)
         self.assertEqual(len(self.r2.get_related_parts()), n)
 
-        # Deleting r2 should remove *all* relationships
+        # Deleting r2 should remove *all* newly created relationships
         self.r2.delete()
-        self.assertEqual(PartRelated.objects.count(), 0)
+        self.assertEqual(PartRelated.objects.count(), countbefore)
 
     def test_stocktake(self):
         """Test for adding stocktake data"""

InvenTree/stock/api.py

@@ -1430,7 +1430,10 @@ stock_api_urls = [
 
     # StockItemTestResult API endpoints
     re_path(r'^test/', include([
-        path(r'<int:pk>/', StockItemTestResultDetail.as_view(), name='api-stock-test-result-detail'),
+        path(r'<int:pk>/', include([
+            re_path(r'^metadata/', MetadataView.as_view(), {'model': StockItemTestResult}, name='api-stock-test-result-metadata'),
+            re_path(r'^.*$', StockItemTestResultDetail.as_view(), name='api-stock-test-result-detail'),
+        ])),
         re_path(r'^.*$', StockItemTestResultList.as_view(), name='api-stock-test-result-list'),
     ])),
 

InvenTree/stock/migrations/0101_stockitemtestresult_metadata.py

@@ -0,0 +1,18 @@
+# Generated by Django 3.2.19 on 2023-05-25 16:06
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('stock', '0100_stockitem_consumed_by'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='stockitemtestresult',
+            name='metadata',
+            field=models.JSONField(blank=True, help_text='JSON metadata field, for use by external plugins', null=True, verbose_name='Plugin Metadata'),
+        ),
+    ]

InvenTree/stock/models.py

@@ -2170,7 +2170,7 @@ def rename_stock_item_test_result_attachment(instance, filename):
     return os.path.join('stock_files', str(instance.stock_item.pk), os.path.basename(filename))
 
 
-class StockItemTestResult(models.Model):
+class StockItemTestResult(MetadataMixin, models.Model):
     """A StockItemTestResult records results of custom tests against individual StockItem objects.
 
     This is useful for tracking unit acceptance tests, and particularly useful when integrated

InvenTree/stock/test_api.py

@@ -1693,3 +1693,62 @@ class StockMergeTest(StockAPITestCase):
 
         # Total number of stock items has been reduced!
         self.assertEqual(StockItem.objects.filter(part=self.part).count(), n - 2)
+
+
+class StockMetadataAPITest(InvenTreeAPITestCase):
+    """Unit tests for the various metadata endpoints of API."""
+
+    fixtures = [
+        'category',
+        'part',
+        'bom',
+        'company',
+        'location',
+        'supplier_part',
+        'stock',
+        'stock_tests',
+    ]
+
+    roles = [
+        'stock.change',
+        'stock_location.change',
+    ]
+
+    def metatester(self, apikey, model):
+        """Generic tester"""
+
+        modeldata = model.objects.first()
+
+        # Useless test unless a model object is found
+        self.assertIsNotNone(modeldata)
+
+        url = reverse(apikey, kwargs={'pk': modeldata.pk})
+
+        # Metadata is initially null
+        self.assertIsNone(modeldata.metadata)
+
+        numstr = f'12{len(apikey)}'
+
+        self.patch(
+            url,
+            {
+                'metadata': {
+                    f'abc-{numstr}': f'xyz-{apikey}-{numstr}',
+                }
+            },
+            expected_code=200
+        )
+
+        # Refresh
+        modeldata.refresh_from_db()
+        self.assertEqual(modeldata.get_metadata(f'abc-{numstr}'), f'xyz-{apikey}-{numstr}')
+
+    def test_metadata(self):
+        """Test all endpoints"""
+
+        for apikey, model in {
+            'api-location-metadata': StockLocation,
+            'api-stock-test-result-metadata': StockItemTestResult,
+            'api-stock-item-metadata': StockItem,
+        }.items():
+            self.metatester(apikey, model)