1 files changed, 24 insertions, 12 deletions
diff --git a/lib/pleroma/ecto_type/activity_pub/object_validators/recipients.ex b/lib/pleroma/ecto_type/activity_pub/object_validators/recipients.ex
index af4b0e527..06fed8fb3 100644
--- a/lib/pleroma/ecto_type/activity_pub/object_validators/recipients.ex
+++ b/lib/pleroma/ecto_type/activity_pub/object_validators/recipients.ex
@@ -13,21 +13,33 @@ defmodule Pleroma.EctoType.ActivityPub.ObjectValidators.Recipients do
     cast([object])
   end
 
+  def cast(object) when is_map(object) do
+    case ObjectID.cast(object) do
+      {:ok, data} -> {:ok, [data]}
+      _ -> :error
+    end
+  end
+
   def cast(data) when is_list(data) do
-    data
-    |> Enum.reduce_while({:ok, []}, fn element, {:ok, list} ->
-      case ObjectID.cast(element) do
-        {:ok, id} ->
-          {:cont, {:ok, [id | list]}}
-
-        _ ->
-          {:halt, :error}
-      end
-    end)
+    data =
+      data
+      |> Enum.reduce_while([], fn element, list ->
+        case ObjectID.cast(element) do
+          {:ok, id} ->
+            {:cont, [id | list]}
+
+          _ ->
+            {:cont, list}
+        end
+      end)
+      |> Enum.sort()
+      |> Enum.uniq()
+
+    {:ok, data}
   end
 
-  def cast(_) do
-    :error
+  def cast(data) do
+    {:error, data}
   end
 
   def dump(data) do