feat(beatmap): implement GET /beatmaps

app/router/beatmap.py

@@ -10,8 +10,9 @@ from app.dependencies.user import get_current_user
 
 from .api_router import router
 
-from fastapi import Depends, HTTPException
-from sqlmodel import Session, select
+from fastapi import Depends, HTTPException, Query
+from pydantic import BaseModel
+from sqlmodel import Session, col, select
 
 
 @router.get("/beatmaps/{bid}", tags=["beatmap"], response_model=BeatmapResp)
@@ -24,3 +25,27 @@ async def get_beatmap(
     if not beatmap:
         raise HTTPException(status_code=404, detail="Beatmap not found")
     return BeatmapResp.from_db(beatmap)
+
+
+class BatchGetResp(BaseModel):
+    beatmaps: list[BeatmapResp]
+
+
+@router.get("/beatmaps", tags=["beatmap"], response_model=BatchGetResp)
+@router.get("/beatmaps/", tags=["beatmap"], response_model=BatchGetResp)
+async def batch_get_beatmaps(
+    b_ids: list[int] = Query(alias="id", default_factory=list),
+    current_user: DBUser = Depends(get_current_user),
+    db: Session = Depends(get_db),
+):
+    if not b_ids:
+        # select 50 beatmaps by last_updated
+        beatmaps = db.exec(
+            select(Beatmap).order_by(col(Beatmap.last_updated).desc()).limit(50)
+        ).all()
+    else:
+        beatmaps = db.exec(
+            select(Beatmap).where(col(Beatmap.id).in_(b_ids)).limit(50)
+        ).all()
+
+    return BatchGetResp(beatmaps=[BeatmapResp.from_db(bm) for bm in beatmaps])