feat(api): add compact hydraulic playback endpoints

2026-11-15 23:36:29 +08:00
parent dd31f7c159
commit f5f972bbec
5 changed files with 427 additions and 0 deletions
@@ -0,0 +1,69 @@
+"""Project-authorized compact hydraulic playback transport."""
+
+from collections import OrderedDict
+import asyncio
+import time
+
+from fastapi import APIRouter, Depends, HTTPException, Query, Response
+from psycopg import AsyncConnection
+
+from app.auth.project_dependencies import ProjectContext, get_project_context, get_project_pg_connection
+from app.services.hydraulic_playback import MAX_FRAME_COUNT, PlaybackGeometry, read_frames, read_geometry
+from app.domain.time import parse_utc_time
+from .dependencies import get_timescale_connection
+
+router = APIRouter(prefix="/timeseries/realtime/playback")
+# Bounded per-process cache, private to the authorized project and database route.
+_cache: OrderedDict[tuple, tuple[float, PlaybackGeometry]] = OrderedDict()
+_load_lock = asyncio.Lock()
+
+
+async def geometry_for_project(ctx: ProjectContext, conn: AsyncConnection) -> PlaybackGeometry:
+    key = (str(ctx.project_id), conn.info.host, conn.info.port, conn.info.dbname)
+    cached = _cache.get(key)
+    if cached and time.monotonic() - cached[0] < 60:
+        _cache.move_to_end(key)
+        return cached[1]
+    async with _load_lock:
+        cached = _cache.get(key)
+        if cached and time.monotonic() - cached[0] < 60:
+            return cached[1]
+        geometry = await read_geometry(conn)
+        _cache[key] = (time.monotonic(), geometry)
+        _cache.move_to_end(key)
+        while len(_cache) > 4:
+            _cache.popitem(last=False)
+        return geometry
+
+
+@router.get("/geometry", summary="读取带版本的水力专题层静态几何")
+async def playback_geometry(ctx: ProjectContext = Depends(get_project_context),
+                            conn: AsyncConnection = Depends(get_project_pg_connection)):
+    try:
+        geometry = await geometry_for_project(ctx, conn)
+    except ValueError as exc:
+        raise HTTPException(422, str(exc)) from exc
+    return Response(geometry.content, media_type="application/octet-stream",
+                    headers={"Cache-Control": "private, no-store", "ETag": f'"{geometry.version}"'})
+
+
+@router.get("/frames", summary="读取索引一致的 Float32 水力时间块")
+async def playback_frames(
+    start_time: str,
+    model_version: str = Query(min_length=24, max_length=24),
+    frame_count: int = Query(default=4, ge=1, le=MAX_FRAME_COUNT),
+    step_seconds: int = Query(default=900, ge=60, le=3600),
+    ctx: ProjectContext = Depends(get_project_context),
+    pg_conn: AsyncConnection = Depends(get_project_pg_connection),
+    ts_conn: AsyncConnection = Depends(get_timescale_connection),
+):
+    try:
+        start = parse_utc_time(start_time, field_name="start_time")
+        geometry = await geometry_for_project(ctx, pg_conn)
+        if geometry.version != model_version:
+            raise HTTPException(409, "管网模型已更新，请重新加载专题层")
+        content = await read_frames(ts_conn, geometry, start, frame_count, step_seconds)
+    except ValueError as exc:
+        raise HTTPException(422, str(exc)) from exc
+    return Response(content, media_type="application/octet-stream",
+                    headers={"Cache-Control": "private, no-store"})