From b3e67ffe3aa61047be950f0f07cad09fe767269a Mon Sep 17 00:00:00 2001
From: Jamie Bliss <jamie@ivyleav.es>
Date: Thu, 9 Nov 2023 14:51:09 -0500
Subject: [PATCH] Implement reaction aggregation.

---
 activities/models/post.py                 | 14 ++++-
 tests/activities/models/test_reactions.py | 77 +++++++++++++++++++++++
 2 files changed, 90 insertions(+), 1 deletion(-)

diff --git a/activities/models/post.py b/activities/models/post.py
index 3b08de2..1e7073c 100644
--- a/activities/models/post.py
+++ b/activities/models/post.py
@@ -610,12 +610,24 @@ class Post(StatorModel):
             "likes": self.interactions.filter(
                 type=PostInteraction.Types.like,
                 state__in=PostInteractionStates.group_active(),
-            ).count(),
+            )
+            .values("identity")
+            .distinct()
+            .count(),  # This counts each user that's had any likes/reactions
             "boosts": self.interactions.filter(
                 type=PostInteraction.Types.boost,
                 state__in=PostInteractionStates.group_active(),
             ).count(),
             "replies": Post.objects.filter(in_reply_to=self.object_uri).count(),
+            "reactions": {
+                row["value"]: row["count"]
+                for row in self.interactions.filter(
+                    type=PostInteraction.Types.like,
+                    state__in=PostInteractionStates.group_active(),
+                )
+                .values("value")
+                .annotate(count=models.Count("identity"))
+            },
         }
         if save:
             self.save()
diff --git a/tests/activities/models/test_reactions.py b/tests/activities/models/test_reactions.py
index 40313ff..ea073a1 100644
--- a/tests/activities/models/test_reactions.py
+++ b/tests/activities/models/test_reactions.py
@@ -230,6 +230,83 @@ def test_react_undo_mismatched(
     assert len(events) == 1
 
 
+@pytest.mark.django_db
+@pytest.mark.parametrize("local", [True, False])
+@pytest.mark.parametrize("reaction", ["\U0001F607"])
+def test_react_stats(
+    identity: Identity,
+    other_identity: Identity,
+    remote_identity: Identity,
+    stator,
+    local: bool,
+    reaction: str,
+):
+    """
+    Checks basic post stats generation
+    """
+    post = Post.create_local(author=identity, content="I love birds!")
+    if local:
+        PostService(post).like_as(other_identity, reaction)
+    else:
+        message = {
+            "id": "test",
+            "type": "Like",
+            "actor": remote_identity.actor_uri,
+            "object": post.object_uri,
+            "content": reaction,
+        }
+        InboxMessage.objects.create(message=message)
+
+    # Run stator thrice - to receive the post, make fanouts and then process them
+    stator.run_single_cycle()
+    stator.run_single_cycle()
+    stator.run_single_cycle()
+
+    post.refresh_from_db()
+
+    assert "reactions" in post.stats
+    assert post.stats["reactions"] == {reaction: 1}
+
+
+@pytest.mark.django_db
+@pytest.mark.parametrize("local", [True, False])
+def test_react_stats_multiple(
+    identity: Identity,
+    other_identity: Identity,
+    remote_identity: Identity,
+    stator,
+    local: bool,
+):
+    """
+    Ensures that multiple reactions get aggregated correctly.
+
+    Basically, if the same person leaves multiple reactions, aggregate all of them into one Like.
+    """
+    post = Post.create_local(author=identity, content="I love birds!")
+    for i, reaction in enumerate("abc"):
+        if local:
+            PostService(post).like_as(other_identity, reaction)
+        else:
+            message = {
+                "id": f"test{i}",
+                "type": "Like",
+                "actor": remote_identity.actor_uri,
+                "object": post.object_uri,
+                "content": reaction,
+            }
+            InboxMessage.objects.create(message=message)
+
+    # Run stator thrice - to receive the post, make fanouts and then process them
+    stator.run_single_cycle()
+    stator.run_single_cycle()
+    stator.run_single_cycle()
+
+    post.refresh_from_db()
+
+    assert post.stats["reactions"] == {"a": 1, "b": 1, "c": 1}
+    assert post.stats["likes"] == 1
+
+
 # TODO: Test that multiple reactions can be added and deleted correctly
 
 # TODO: How should plain likes and reactions from the same source be handled?