Add contenttype model to API (#7079)

* Add contenttype APIs

* add plugin and id identifier

* resolve via modelname

* bump API version

* differentiate model view ids

* add API test

* remove unneeded response

src/backend/InvenTree/InvenTree/api_version.py

@@ -1,11 +1,14 @@
 """InvenTree API version information."""
 
 # InvenTree API version
-INVENTREE_API_VERSION = 190
+INVENTREE_API_VERSION = 191
 """Increment this API version number whenever there is a significant change to the API that any clients need to know about."""
 
 INVENTREE_API_TEXT = """
 
+v191 - 2024-04-22 : https://github.com/inventree/InvenTree/pull/7079
+    - Adds API endpoints for Contenttype model
+
 v190 - 2024-04-19 : https://github.com/inventree/InvenTree/pull/7024
     - Adds "active" field to the Company API endpoints
     - Allow company list to be filtered by "active" status

src/backend/InvenTree/InvenTree/metadata.py

@@ -280,6 +280,8 @@ class InvenTreeMetadata(SimpleMetadata):
                 # Special case for 'user' model
                 if field_info['model'] == 'user':
                     field_info['api_url'] = '/api/user/'
+                elif field_info['model'] == 'contenttype':
+                    field_info['api_url'] = '/api/contenttype/'
                 else:
                     field_info['api_url'] = model.get_api_url()
 

src/backend/InvenTree/common/api.py

@@ -3,6 +3,7 @@
 import json
 
 from django.conf import settings
+from django.contrib.contenttypes.models import ContentType
 from django.http.response import HttpResponse
 from django.urls import include, path, re_path
 from django.utils.decorators import method_decorator
@@ -619,6 +620,38 @@ class FlagDetail(RetrieveAPI):
         return {key: value}
 
 
+class ContentTypeList(ListAPI):
+    """List view for ContentTypes."""
+
+    queryset = ContentType.objects.all()
+    serializer_class = common.serializers.ContentTypeSerializer
+    permission_classes = [permissions.IsAuthenticated]
+
+
+class ContentTypeDetail(RetrieveAPI):
+    """Detail view for a ContentType model."""
+
+    queryset = ContentType.objects.all()
+    serializer_class = common.serializers.ContentTypeSerializer
+    permission_classes = [permissions.IsAuthenticated]
+
+
+@extend_schema(operation_id='contenttype_retrieve_model')
+class ContentTypeModelDetail(ContentTypeDetail):
+    """Detail view for a ContentType model."""
+
+    def get_object(self):
+        """Attempt to find a ContentType object with the provided key."""
+        model_ref = self.kwargs.get('model', None)
+        if model_ref:
+            qs = self.filter_queryset(self.get_queryset())
+            try:
+                return qs.get(model=model_ref)
+            except ContentType.DoesNotExist:
+                raise NotFound()
+        raise NotFound()
+
+
 settings_api_urls = [
     # User settings
     path(
@@ -799,6 +832,21 @@ common_api_urls = [
             path('', AllStatusViews.as_view(), name='api-status-all'),
         ]),
     ),
+    # Contenttype
+    path(
+        'contenttype/',
+        include([
+            path(
+                '<int:pk>/', ContentTypeDetail.as_view(), name='api-contenttype-detail'
+            ),
+            path(
+                '<str:model>/',
+                ContentTypeModelDetail.as_view(),
+                name='api-contenttype-detail-modelname',
+            ),
+            path('', ContentTypeList.as_view(), name='api-contenttype-list'),
+        ]),
+    ),
 ]
 
 admin_api_urls = [

src/backend/InvenTree/common/serializers.py

@@ -1,5 +1,6 @@
 """JSON serializers for common components."""
 
+from django.contrib.contenttypes.models import ContentType
 from django.db.models import OuterRef, Subquery
 from django.urls import reverse
 from django.utils.translation import gettext_lazy as _
@@ -16,6 +17,7 @@ from InvenTree.serializers import (
     InvenTreeImageSerializerField,
     InvenTreeModelSerializer,
 )
+from plugin import registry as plugin_registry
 from users.serializers import OwnerSerializer
 
 
@@ -303,6 +305,26 @@ class FlagSerializer(serializers.Serializer):
         return data
 
 
+class ContentTypeSerializer(serializers.Serializer):
+    """Serializer for ContentType models."""
+
+    pk = serializers.IntegerField(read_only=True)
+    app_label = serializers.CharField(read_only=True)
+    model = serializers.CharField(read_only=True)
+    app_labeled_name = serializers.CharField(read_only=True)
+    is_plugin = serializers.SerializerMethodField('get_is_plugin', read_only=True)
+
+    class Meta:
+        """Meta options for ContentTypeSerializer."""
+
+        model = ContentType
+        fields = ['pk', 'app_label', 'model', 'app_labeled_name', 'is_plugin']
+
+    def get_is_plugin(self, obj) -> bool:
+        """Return True if the model is a plugin model."""
+        return obj.app_label in plugin_registry.installed_apps
+
+
 class CustomUnitSerializer(InvenTreeModelSerializer):
     """DRF serializer for CustomUnit model."""
 

src/backend/InvenTree/common/tests.py

@@ -8,6 +8,7 @@ from http import HTTPStatus
 from unittest import mock
 
 from django.contrib.auth import get_user_model
+from django.contrib.contenttypes.models import ContentType
 from django.core.cache import cache
 from django.core.exceptions import ValidationError
 from django.core.files.uploadedfile import SimpleUploadedFile
@@ -1339,3 +1340,46 @@ class CustomUnitAPITest(InvenTreeAPITestCase):
 
         for name in invalid_name_values:
             self.patch(url, {'name': name}, expected_code=400)
+
+
+class ContentTypeAPITest(InvenTreeAPITestCase):
+    """Unit tests for the ContentType API."""
+
+    def test_list(self):
+        """Test API list functionality."""
+        response = self.get(reverse('api-contenttype-list'), expected_code=200)
+        self.assertEqual(len(response.data), ContentType.objects.count())
+
+    def test_detail(self):
+        """Test API detail functionality."""
+        ct = ContentType.objects.first()
+        assert ct
+
+        response = self.get(
+            reverse('api-contenttype-detail', kwargs={'pk': ct.pk}), expected_code=200
+        )
+
+        self.assertEqual(response.data['app_label'], ct.app_label)
+        self.assertEqual(response.data['model'], ct.model)
+
+        # Test with model name
+        response = self.get(
+            reverse('api-contenttype-detail-modelname', kwargs={'model': ct.model}),
+            expected_code=200,
+        )
+        self.assertEqual(response.data['app_label'], ct.app_label)
+        self.assertEqual(response.data['model'], ct.model)
+
+        # Test non-existent model
+        self.get(
+            reverse(
+                'api-contenttype-detail-modelname', kwargs={'model': 'nonexistent'}
+            ),
+            expected_code=404,
+        )
+
+        # PK should not work on model name endpoint
+        self.get(
+            reverse('api-contenttype-detail-modelname', kwargs={'model': None}),
+            expected_code=404,
+        )