From 571c894278780f1802e67df2979c73224229d211 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=EC=9C=A4=EC=A0=95=EB=AF=BC?= <baekryang@bnovalab.com>
Date: Thu, 28 May 2026 17:34:44 +0900
Subject: [PATCH] Parallelize multi-year rank fetch (R7)

fetchRankFromKbo awaited each year's getOrFetch sequentially even though
years use independent cache keys. Map to Promise.all so multi-year lookups
run concurrently; order is preserved.
---
 src/repositories/kboRepository.ts | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/src/repositories/kboRepository.ts b/src/repositories/kboRepository.ts
index 534842f..bf39145 100644
--- a/src/repositories/kboRepository.ts
+++ b/src/repositories/kboRepository.ts
@@ -43,15 +43,16 @@ const TTL_MS = 60 * 60 * 1000; // 1 hour
 export async function fetchRankFromKbo(
   years: number[]
 ): Promise<TeamRankResult[]> {
-  const results: TeamRankResult[] = [];
-  for (const year of years) {
-    const key = encodeKey(["rank", year]);
-    const result = await getOrFetch<TeamRankResult>(key, TTL_MS, () =>
-      fetchSingleYearRank(year)
-    );
-    results.push(result);
-  }
-  return results;
+  // 연도별로 독립 캐시 키를 쓰므로 순차 대기할 이유가 없다. 병렬 처리해 다년도
+  // 조회 지연을 줄인다. Promise.all은 입력 순서를 보존한다.
+  return Promise.all(
+    years.map((year) => {
+      const key = encodeKey(["rank", year]);
+      return getOrFetch<TeamRankResult>(key, TTL_MS, () =>
+        fetchSingleYearRank(year)
+      );
+    })
+  );
 }
 
 /**