From 31a420cf5c446249ba52e0ddcb2937e99f6e3e84 Mon Sep 17 00:00:00 2001
From: Geert Rademakes <g26107@eon.com>
Date: Fri, 8 Aug 2025 09:18:48 +0200
Subject: [PATCH] perf(backend): reduce projection for playlist total duration
 calculation; fewer fields fetched

---
 packages/backend/src/routes/songs.ts | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/packages/backend/src/routes/songs.ts b/packages/backend/src/routes/songs.ts
index d4c0e96..d674ce4 100644
--- a/packages/backend/src/routes/songs.ts
+++ b/packages/backend/src/routes/songs.ts
@@ -153,8 +153,7 @@ router.get('/playlist/*', async (req: Request, res: Response) => {
     const totalPages = Math.ceil(totalSongs / limit);
 
     // Calculate total duration for the entire playlist
-    const allPlaylistSongs = await Song.find({ id: { $in: trackIds } }).lean();
-    const totalDuration = allPlaylistSongs.reduce((total, song: any) => {
+    const totalDuration = (await Song.find({ id: { $in: trackIds } }, { totalTime: 1 }).lean()).reduce((total, song: any) => {
       if (!song.totalTime) return total;
       const totalTimeStr = String(song.totalTime);
       const seconds = Math.floor(Number(totalTimeStr) / (totalTimeStr.length > 4 ? 1000 : 1));