[WEB-6528] fix: External API returns 404 when retrieving an epic by work item identifier (#6196)

* fix: allow epics in work item identifier endpoint

* fix: allow intake work items as well

* fix: remove is_epic and is_intake

* fix: remove unused imports

* fix: update the tests

apps/api/plane/api/views/issue.py

@@ -271,25 +271,6 @@ class WorkspaceIssueAPIEndpoint(BaseAPIView):
         Retrieve a specific work item using workspace slug, project identifier, and issue identifier.
         This endpoint provides workspace-level access to work items.
         """
-        # ee start
-        # epics support
-        if request.GET.get("include_epics") == "true" and issue_identifier and project_identifier:
-            issue = Issue.issue_and_epics_objects.annotate(
-                sub_issues_count=Issue.issue_and_epics_objects.filter(parent=OuterRef("id"))
-                .order_by()
-                .annotate(count=Func(F("id"), function="Count"))
-                .values("count")
-            ).get(
-                workspace__slug=slug,
-                project__identifier=project_identifier,
-                sequence_id=issue_identifier,
-            )
-            return Response(
-                IssueSerializer(issue, fields=self.fields, expand=self.expand).data,
-                status=status.HTTP_200_OK,
-            )
-        # ee end
-
         # Ensure labels and assignees are always expanded for issue details
         # this is required until we find a better way to create issue detail serializer
         expand = self.expand or []
@@ -297,15 +278,22 @@ class WorkspaceIssueAPIEndpoint(BaseAPIView):
         expand = list(set(expand) | required_expansions)
 
         if issue_identifier and project_identifier:
-            issue = Issue.issue_objects.annotate(
-                sub_issues_count=Issue.issue_objects.filter(parent=OuterRef("id"))
-                .order_by()
-                .annotate(count=Func(F("id"), function="Count"))
-                .values("count")
-            ).get(
-                workspace__slug=slug,
-                project__identifier=project_identifier,
-                sequence_id=issue_identifier,
+            # Use Issue.objects to support retrieving work items,
+            # epics, intake items, and drafts by identifier.
+            issue = (
+                Issue.objects.exclude(archived_at__isnull=False)
+                .exclude(project__archived_at__isnull=False)
+                .annotate(
+                    sub_issues_count=Issue.objects.filter(parent=OuterRef("id"))
+                    .order_by()
+                    .annotate(count=Func(F("id"), function="Count"))
+                    .values("count"),
+                )
+                .get(
+                    workspace__slug=slug,
+                    project__identifier=project_identifier,
+                    sequence_id=issue_identifier,
+                )
             )
             return Response(
                 IssueDetailSerializer(issue, fields=self.fields, expand=expand).data,

apps/api/plane/tests/unit/ee/test_epic_endpoints.py

@@ -31,7 +31,7 @@ class TestEpicEndpoints:
         assert response.data["id"] == epic.id
 
     def test_get_epic_by_identifier(self, api_key_client, workspace, project, epic, create_user):
-        """Test that an epic can be retrieved by identifier"""
+        """Test that an epic can be retrieved by identifier without include_epics param"""
         # Add user as project member to fix 403 error
         ProjectMember.objects.create(project=project, member=create_user, role=20, is_active=True)
 
@@ -43,7 +43,6 @@ class TestEpicEndpoints:
                 "issue_identifier": epic.sequence_id,
             },
         )
-        url += "?include_epics=true"
         response = api_key_client.get(url)
         assert response.status_code == status.HTTP_200_OK
         assert response.data["id"] == epic.id