object: add support for preloading objects when walking an activity graph in normal form

lib/pleroma/object.ex

@@ -14,6 +14,8 @@ defmodule Pleroma.Object do
   import Ecto.Query
   import Ecto.Changeset
 
+  require Logger
+
   schema "objects" do
     field(:data, :map)
 
@@ -38,6 +40,29 @@ defmodule Pleroma.Object do
     Repo.one(from(object in Object, where: fragment("(?)->>'id' = ?", object.data, ^ap_id)))
   end
 
+  # If we pass an Activity to Object.normalize(), we can try to use the preloaded object.
+  # Use this whenever possible, especially when walking graphs in an O(N) loop!
+  def normalize(%Activity{object: %Object{} = object}), do: object
+
+  # Catch and log Object.normalize() calls where the Activity's child object is not
+  # preloaded.
+  def normalize(%Activity{data: %{"object" => %{"id" => ap_id}}}) do
+    Logger.info(
+      "Object.normalize() called without preloaded object (#{ap_id}).  Consider preloading the object!"
+    )
+
+    normalize(ap_id)
+  end
+
+  def normalize(%Activity{data: %{"object" => ap_id}}) do
+    Logger.info(
+      "Object.normalize() called without preloaded object (#{ap_id}).  Consider preloading the object!"
+    )
+
+    normalize(ap_id)
+  end
+
+  # Old way, try fetching the object through cache.
   def normalize(%{"id" => ap_id}), do: normalize(ap_id)
   def normalize(ap_id) when is_binary(ap_id), do: get_cached_by_ap_id(ap_id)
   def normalize(_), do: nil