Merge branch 'unlisted-fix' into 'develop'

Public getting stripped from unlisted activity CC

See merge request pleroma/pleroma!4353

changelog.d/preserve-public-cc.fix

@@ -0,0 +1 @@
+Fix federation issue where Public visibility information in cc field was lost when sent to remote servers, causing posts to appear with inconsistent visibility across instances

lib/pleroma/web/activity_pub/publisher.ex

@@ -93,7 +93,20 @@ defmodule Pleroma.Web.ActivityPub.Publisher do
 
     {:ok, data} = Transmogrifier.prepare_outgoing(activity.data)
 
-    cc = Map.get(params, :cc, [])
+    param_cc = Map.get(params, :cc, [])
+
+    original_cc = Map.get(data, "cc", [])
+
+    public_address = Pleroma.Constants.as_public()
+
+    # Ensure unlisted posts don't lose the public address in the cc
+    # if the param_cc was set
+    cc =
+      if public_address in original_cc and public_address not in param_cc do
+        [public_address | param_cc]
+      else
+        param_cc
+      end
 
     json =
       data

test/pleroma/web/activity_pub/publisher_test.exs

@@ -520,4 +520,105 @@ defmodule Pleroma.Web.ActivityPub.PublisherTest do
 
     assert decoded["cc"] == []
   end
+
+  test "unlisted activities retain public address in cc" do
+    user = insert(:user)
+
+    # simulate unlistd activity by only having
+    # public address in cc
+    activity =
+      insert(:note_activity,
+        user: user,
+        data_attrs: %{
+          "cc" => [@as_public],
+          "to" => [user.follower_address]
+        }
+      )
+
+    assert @as_public in activity.data["cc"]
+
+    prepared =
+      Publisher.prepare_one(%{
+        inbox: "https://remote.instance/users/someone/inbox",
+        activity_id: activity.id
+      })
+
+    {:ok, decoded} = Jason.decode(prepared.json)
+
+    assert @as_public in decoded["cc"]
+
+    # maybe we also have another inbox in cc
+    # during Publishing
+    activity =
+      insert(:note_activity,
+        user: user,
+        data_attrs: %{
+          "cc" => [@as_public],
+          "to" => [user.follower_address]
+        }
+      )
+
+    prepared =
+      Publisher.prepare_one(%{
+        inbox: "https://remote.instance/users/someone/inbox",
+        activity_id: activity.id,
+        cc: ["https://remote.instance/users/someone_else/inbox"]
+      })
+
+    {:ok, decoded} = Jason.decode(prepared.json)
+
+    assert decoded["cc"] == [@as_public, "https://remote.instance/users/someone_else/inbox"]
+  end
+
+  test "public address in cc parameter is preserved" do
+    user = insert(:user)
+
+    cc_with_public = [@as_public, "https://example.org/users/other"]
+
+    activity =
+      insert(:note_activity,
+        user: user,
+        data_attrs: %{
+          "cc" => cc_with_public,
+          "to" => [user.follower_address]
+        }
+      )
+
+    assert @as_public in activity.data["cc"]
+
+    prepared =
+      Publisher.prepare_one(%{
+        inbox: "https://remote.instance/users/someone/inbox",
+        activity_id: activity.id,
+        cc: cc_with_public
+      })
+
+    {:ok, decoded} = Jason.decode(prepared.json)
+
+    assert cc_with_public == decoded["cc"]
+  end
+
+  test "cc parameter is preserved" do
+    user = insert(:user)
+
+    activity =
+      insert(:note_activity,
+        user: user,
+        data_attrs: %{
+          "cc" => ["https://example.com/specific/user"],
+          "to" => [user.follower_address]
+        }
+      )
+
+    prepared =
+      Publisher.prepare_one(%{
+        inbox: "https://remote.instance/users/someone/inbox",
+        activity_id: activity.id,
+        cc: ["https://example.com/specific/user"]
+      })
+
+    {:ok, decoded} = Jason.decode(prepared.json)
+
+    assert decoded["cc"] == ["https://example.com/specific/user"]
+  end
 end