From 232894cd86a8d7ff5a4be39a0cd9bfec851df77b Mon Sep 17 00:00:00 2001
From: Hazelnoot <acomputerdog@gmail.com>
Date: Thu, 5 Jun 2025 00:35:22 -0400
Subject: [PATCH] fix performance regression in home timeline

---
 .../server/api/endpoints/notes/timeline.ts    | 73 +++++--------------
 1 file changed, 18 insertions(+), 55 deletions(-)

diff --git a/packages/backend/src/server/api/endpoints/notes/timeline.ts b/packages/backend/src/server/api/endpoints/notes/timeline.ts
index a23a61373e..d898748ac7 100644
--- a/packages/backend/src/server/api/endpoints/notes/timeline.ts
+++ b/packages/backend/src/server/api/endpoints/notes/timeline.ts
@@ -140,64 +140,27 @@ export default class extends Endpoint<typeof meta, typeof paramDef> { // eslint-
 	}
 
 	private async getFromDb(ps: { untilId: string | null; sinceId: string | null; limit: number; withFiles: boolean; withRenotes: boolean; withBots: boolean; }, me: MiLocalUser) {
-		const followees = await this.userFollowingService.getFollowees(me.id);
-		const followingChannels = await this.channelFollowingsRepository.find({
-			where: {
-				followerId: me.id,
-			},
-		});
-
 		//#region Construct query
 		const query = this.queryService.makePaginationQuery(this.notesRepository.createQueryBuilder('note'), ps.sinceId, ps.untilId)
 			.innerJoinAndSelect('note.user', 'user')
 			.leftJoinAndSelect('note.reply', 'reply')
 			.leftJoinAndSelect('note.renote', 'renote')
-			.leftJoinAndSelect('reply.user', 'replyUser', 'replyUser.id = note.replyUserId')
-			.leftJoinAndSelect('renote.user', 'renoteUser', 'renoteUser.id = note.renoteUserId');
-
-		if (followees.length > 0 && followingChannels.length > 0) {
-			// ユーザー・チャンネルともにフォローあり
-			const meOrFolloweeIds = [me.id, ...followees.map(f => f.followeeId)];
-			const followingChannelIds = followingChannels.map(x => x.followeeId);
-			query.andWhere(new Brackets(qb => {
-				qb
-					.where(new Brackets(qb2 => {
-						qb2
-							.where('note.userId IN (:...meOrFolloweeIds)', { meOrFolloweeIds: meOrFolloweeIds })
-							.andWhere('note.channelId IS NULL');
-					}))
-					.orWhere('note.channelId IN (:...followingChannelIds)', { followingChannelIds });
-			}));
-		} else if (followees.length > 0) {
-			// ユーザーフォローのみ（チャンネルフォローなし）
-			const meOrFolloweeIds = [me.id, ...followees.map(f => f.followeeId)];
-			query
-				.andWhere('note.channelId IS NULL')
-				.andWhere('note.userId IN (:...meOrFolloweeIds)', { meOrFolloweeIds: meOrFolloweeIds });
-		} else if (followingChannels.length > 0) {
-			// チャンネルフォローのみ（ユーザーフォローなし）
-			const followingChannelIds = followingChannels.map(x => x.followeeId);
-			query.andWhere(new Brackets(qb => {
-				qb
-					.where('note.channelId IN (:...followingChannelIds)', { followingChannelIds })
-					.orWhere('note.userId = :meId', { meId: me.id });
-			}));
-		} else {
-			// フォローなし
-			query
-				.andWhere('note.channelId IS NULL')
-				.andWhere('note.userId = :meId', { meId: me.id });
-		}
-
-		query.andWhere(new Brackets(qb => {
-			qb
-				.where('note.replyId IS NULL') // 返信ではない
-				.orWhere(new Brackets(qb => {
-					qb // 返信だけど投稿者自身への返信
-						.where('note.replyId IS NOT NULL')
-						.andWhere('note.replyUserId = note.userId');
-				}));
-		}));
+			.leftJoinAndSelect('reply.user', 'replyUser')
+			.leftJoinAndSelect('renote.user', 'renoteUser')
+			// 1. in a channel I follow, 2. my own post, 3. by a user I follow
+			.andWhere(new Brackets(qb => this.queryService
+				.orFollowingChannel(qb, ':meId', 'note.channelId')
+				.orWhere(':meId = note.userId')
+				.orWhere(new Brackets(qb2 => this.queryService
+					.andFollowingUser(qb2, ':meId', 'note.userId')
+					.andWhere('note.channelId IS NULL'))),
+			))
+			// 1. Not a reply, 2. a self-reply
+			.andWhere(new Brackets(qb => qb
+				.orWhere('note.replyId IS NULL') // 返信ではない
+				.orWhere('note.replyUserId = note.userId')))
+			.setParameters({ meId: me.id })
+			.limit(ps.limit);
 
 		this.queryService.generateVisibilityQuery(query, me);
 		this.queryService.generateBlockedHostQueryForNote(query);
@@ -212,11 +175,11 @@ export default class extends Endpoint<typeof meta, typeof paramDef> { // eslint-
 
 		if (!ps.withRenotes) {
 			this.queryService.generateExcludedRenotesQueryForNotes(query);
-		} else if (me) {
+		} else {
 			this.queryService.generateMutedUserRenotesQueryForNotes(query, me);
 		}
 		//#endregion
 
-		return await query.limit(ps.limit).getMany();
+		return await query.getMany();
 	}
 }