Support author follow in feed view

src/feed/tests/views/test_feed_view.py

@@ -23,6 +23,7 @@
 from researchhub_document.related_models.researchhub_unified_document_model import (
     ResearchhubUnifiedDocument,
 )
+from user.related_models.author_model import Author
 from user.views.follow_view_mixins import create_follow
 
 User = get_user_model()
@@ -818,3 +819,105 @@ def test_following_feed_default_sorting(self):
                     dates[i + 1],
                     "Feed items not sorted by action_date when using default sort",
                 )
+
+    def test_following_feed_with_followed_author(self):
+        """Test that following an author returns their papers/posts in the feed."""
+        # Arrange
+        followed_author = Author.objects.create(
+            first_name="Followed",
+            last_name="Author",
+        )
+        create_follow(self.user, followed_author)
+
+        # Create a paper by the followed author in a hub we don't follow
+        author_paper_doc = ResearchhubUnifiedDocument.objects.create(
+            document_type="PAPER"
+        )
+        author_paper_doc.hubs.add(self.other_hub)
+        author_paper = Paper.objects.create(
+            title="Paper by Followed Author",
+            paper_publish_date=timezone.now(),
+            unified_document=author_paper_doc,
+        )
+
+        author_paper_entry = FeedEntry.objects.create(
+            user=self.other_user,
+            action="PUBLISH",
+            action_date=timezone.now(),
+            content_type=self.paper_content_type,
+            object_id=author_paper.id,
+            unified_document=author_paper_doc,
+            metrics={"votes": 25, "comments": 5},
+        )
+        author_paper_entry.hubs.add(self.other_hub)
+        author_paper_entry.authors.add(followed_author)
+
+        cache.clear()
+
+        url = reverse("feed-list")
+
+        # Act
+        response = self.client.get(url, {"feed_view": "following"})
+
+        # Assert
+        self.assertEqual(response.status_code, status.HTTP_200_OK)
+        result_ids = [r["content_object"]["id"] for r in response.data["results"]]
+
+        # Should see paper from followed author even though it's in an unfollowed hub
+        self.assertIn(author_paper.id, result_ids)
+        # Should still see paper from followed hub
+        self.assertIn(self.paper.id, result_ids)
+        # Should not see paper from unfollowed hub by unfollowed author
+        self.assertNotIn(self.other_paper.id, result_ids)
+
+    def test_following_feed_with_only_followed_author(self):
+        """Test that following only authors (no hubs) returns their content."""
+        # Arrange
+        # Remove all hub follows
+        self.user.following.all().delete()
+
+        followed_author = Author.objects.create(
+            first_name="Only",
+            last_name="Author",
+        )
+        create_follow(self.user, followed_author)
+
+        # Create a paper by the followed author
+        author_paper_doc = ResearchhubUnifiedDocument.objects.create(
+            document_type="PAPER"
+        )
+        author_paper_doc.hubs.add(self.other_hub)
+        author_paper = Paper.objects.create(
+            title="Paper by Only Followed Author",
+            paper_publish_date=timezone.now(),
+            unified_document=author_paper_doc,
+        )
+
+        author_paper_entry = FeedEntry.objects.create(
+            user=self.other_user,
+            action="PUBLISH",
+            action_date=timezone.now(),
+            content_type=self.paper_content_type,
+            object_id=author_paper.id,
+            unified_document=author_paper_doc,
+            metrics={"votes": 25, "comments": 5},
+        )
+        author_paper_entry.hubs.add(self.other_hub)
+        author_paper_entry.authors.add(followed_author)
+
+        cache.clear()
+
+        url = reverse("feed-list")
+
+        # Act
+        response = self.client.get(url, {"feed_view": "following"})
+
+        # Assert
+        self.assertEqual(response.status_code, status.HTTP_200_OK)
+        result_ids = [r["content_object"]["id"] for r in response.data["results"]]
+
+        # Should see paper from followed author
+        self.assertIn(author_paper.id, result_ids)
+        # Should not see papers from unfollowed hubs/authors
+        self.assertNotIn(self.paper.id, result_ids)
+        self.assertNotIn(self.other_paper.id, result_ids)

src/feed/views/feed_view.py

@@ -6,7 +6,7 @@
 
 from django.conf import settings
 from django.core.cache import cache
-from django.db.models import Case, IntegerField, Value, When
+from django.db.models import Case, IntegerField, Q, Value, When
 from rest_framework import status
 from rest_framework.decorators import action
 from rest_framework.permissions import AllowAny
@@ -124,10 +124,16 @@ def get_queryset(self):
         # Apply following filter only for "following" view
         if feed_view == "following":
             followed_hub_ids = self.get_followed_hub_ids()
-            if followed_hub_ids:
-                queryset = queryset.filter(
-                    hubs__id__in=followed_hub_ids,
-                )
+            followed_author_ids = self.get_followed_author_ids()
+
+            if followed_hub_ids or followed_author_ids:
+                following_filter = Q()
+                if followed_hub_ids:
+                    following_filter |= Q(hubs__id__in=followed_hub_ids)
+                if followed_author_ids:
+                    following_filter |= Q(authors__id__in=followed_author_ids)
+
+                queryset = queryset.filter(following_filter)
 
             # Only show paper and post for all following views
             queryset = queryset.filter(

src/feed/views/feed_view_mixin.py

@@ -9,6 +9,7 @@
 from paper.related_models.paper_model import Paper
 from researchhub_comment.related_models.rh_comment_model import RhCommentModel
 from researchhub_document.related_models.researchhub_post_model import ResearchhubPost
+from user.related_models.author_model import Author
 
 
 class FeedViewMixin:
@@ -20,6 +21,10 @@ class FeedViewMixin:
 
     _content_types = {}
 
+    @property
+    def _author_content_type(self):
+        return self._get_content_type(Author)
+
     @property
     def _comment_content_type(self):
         return self._get_content_type(RhCommentModel)
@@ -211,6 +216,20 @@ def get_followed_hub_ids(self):
             ).values_list("object_id", flat=True)
         )
 
+    def get_followed_author_ids(self):
+        """
+        Get IDs of authors followed by the current user.
+        Returns empty list if user is not authenticated.
+        """
+        if not self.request.user.is_authenticated:
+            return []
+
+        return list(
+            self.request.user.following.filter(
+                content_type=self._author_content_type
+            ).values_list("object_id", flat=True)
+        )
+
     def _get_user_votes(self, created_by, doc_ids, reaction_content_type):
         return Vote.objects.filter(
             content_type=reaction_content_type,