Join on preloads to avoid N+1 queries

lib/pleroma/notification.ex

@@ -35,7 +35,8 @@ defmodule Pleroma.Notification do
         n in Notification,
         where: n.user_id == ^user.id,
         order_by: [desc: n.id],
-        preload: [:activity],
+        join: activity in assoc(n, :activity),
+        preload: [activity: activity],
         limit: 20
       )
 
@@ -66,7 +67,8 @@ defmodule Pleroma.Notification do
       from(
         n in Notification,
         where: n.id == ^id,
-        preload: [:activity]
+        join: activity in assoc(n, :activity),
+        preload: [activity: activity]
       )
 
     notification = Repo.one(query)

lib/pleroma/plugs/oauth_plug.ex

@@ -33,7 +33,12 @@ defmodule Pleroma.Plugs.OAuthPlug do
   #
   @spec fetch_user_and_token(String.t()) :: {:ok, User.t(), Token.t()} | nil
   defp fetch_user_and_token(token) do
-    query = from(q in Token, where: q.token == ^token, preload: [:user])
+    query =
+      from(t in Token,
+        where: t.token == ^token,
+        join: user in assoc(t, :user),
+        preload: [user: user]
+      )
 
     with %Token{user: %{info: %{deactivated: false} = _} = user} = token_record <- Repo.one(query) do
       {:ok, user, token_record}