fix: error when registering TaskResultAdmin on proxy model (#489)

* fix: error when registering TaskResultAdmin on proxy model

* test: add test for registering TaskResultAdmin on proxy model

* fix: conflicts in test_admin and test_migrations

* Update t/unit/test_admin.py

---------

Co-authored-by: Asif Saif Uddin {"Auvi":"অভি"} <auvipy@gmail.com>

Author: ClanEver

django_celery_results/admin.py

@@ -64,7 +64,7 @@ def get_readonly_fields(self, request, obj=None):
             return self.readonly_fields
         else:
             return list({
-                field.name for field in self.opts.local_fields
+                field.name for field in self.model._meta.fields
             })
 
 

t/unit/test_admin.py

@@ -0,0 +1,81 @@
+from celery import uuid
+from django.apps import apps
+from django.contrib import admin
+from django.contrib.auth import get_user_model
+from django.test import TestCase
+from django.urls import (
+    clear_url_caches,
+    get_resolver,
+    path,
+    reverse,
+)
+
+from django_celery_results.admin import TaskResultAdmin
+from django_celery_results.models import TaskResult
+
+User = get_user_model()
+
+
+class TaskResultAdminTests(TestCase):
+    app_name = "django_celery_results"
+    model = TaskResult
+
+    def setUp(self):
+        self.admin_user = User.objects.create_superuser(
+            username="admin", email="admin@test.com", password="password"
+        )
+        self.client.login(username="admin", password="password")
+        self.task_result = TaskResult.objects.create(
+            task_id=uuid(), task_name="test_task"
+        )
+
+    def test_add_view(self):
+        url = reverse(
+            f"admin:{self.app_name}_{self.model._meta.model_name}_add"
+        )
+        response = self.client.get(url)
+        self.assertEqual(response.status_code, 200)
+
+    def test_change_view(self):
+        url = reverse(
+            f"admin:{self.app_name}_{self.model._meta.model_name}_change",
+            args=[self.task_result.id],
+        )
+        response = self.client.get(url)
+        self.assertEqual(response.status_code, 200)
+
+
+class TaskResultProxyAdminTests(TaskResultAdminTests):
+    @classmethod
+    def setUpClass(cls):
+        super().setUpClass()
+
+        class TaskResultProxy(TaskResult):
+            class Meta:
+                proxy = True
+                app_label = "django_celery_results"
+
+        cls.model = TaskResultProxy
+        admin.site.register(TaskResultProxy, TaskResultAdmin)
+
+        # The temporary registration of admin requires refreshing the URL cache
+        # Otherwise, it cannot be resolved
+        default_resolver = get_resolver()
+        cls.ori_url_patterns_0 = default_resolver.url_patterns[0]
+        get_resolver().url_patterns[0] = path("admin/", admin.site.urls)
+        clear_url_caches()
+
+    @classmethod
+    def tearDownClass(cls):
+        super().tearDownClass()
+
+        # Unregister the proxy model
+        admin.site.unregister(cls.model)
+        app_config = apps.get_app_config(cls.app_name)
+        model_name = cls.model._meta.model_name
+        if model_name in app_config.models:
+            del app_config.models[model_name]
+
+        # Restore the original URL patterns
+        get_resolver().url_patterns[0] = cls.ori_url_patterns_0
+        clear_url_caches()