Performance updates

app/api/files/[...key]/route.ts

@@ -2,6 +2,32 @@ import { NextRequest, NextResponse } from "next/server";
 import fs from "fs";
 import path from "path";
 
+// ── Tuning constants ──────────────────────────────────────────────────────────
+//
+// CHUNK_SIZE — maximum bytes returned per Range response.
+//
+// Target workload: 2–20 s H.264 MP4 clips at 30–50 Mbps = ~7–125 MB per file,
+// 1–3 concurrent reviewers on a LAN/office network.
+//
+// At 8 MB each chunk:
+//   • A 7 MB clip (2 s @ 30 Mbps) arrives in a single request.
+//   • A 75 MB clip (20 s @ 30 Mbps) needs ~10 requests total.
+//   • A 125 MB clip (20 s @ 50 Mbps) needs ~16 requests total.
+//
+// The previous 2 MB cap produced 4× as many HTTP round-trips and 4× as many
+// file-open/stat operations for the same content, with no benefit for this
+// workload. Larger values (16 MB+) offer diminishing returns and increase
+// per-request heap pressure.
+const CHUNK_SIZE = 8 * 1024 * 1024; // 8 MB
+
+// READ_HIGH_WATER_MARK — libuv/Node.js internal read-buffer size per stream.
+//
+// Default is 64 KB, meaning an 8 MB chunk requires ~128 kernel→userspace copy
+// iterations. 512 KB reduces that to ~16 iterations, lowering V8 GC pressure
+// and improving throughput for large sequential reads. Still small enough that
+// 3 concurrent streams only hold ~1.5 MB of read buffers in total.
+const READ_HIGH_WATER_MARK = 512 * 1024; // 512 KB
+
 export async function GET(
   req: NextRequest,
   { params }: { params: Promise<{ key: string[] }> }
@@ -10,19 +36,31 @@ export async function GET(
   // key is a catch-all segment array, e.g. ["videos", "uuid-filename.mp4"]
   const relativePath = key.join("/");
 
-  // Sanitize: prevent path traversal
+  // ── Path traversal sanitisation ───────────────────────────────────────────
   const uploadDir = path.resolve(process.env.LOCAL_UPLOAD_DIR ?? "./uploads");
   const filePath = path.resolve(path.join(uploadDir, relativePath));
 
-  if (!filePath.startsWith(uploadDir)) {
+  // Append path.sep so "/uploads2/evil.mp4".startsWith("/uploads") cannot
+  // pass — the resolved path must be strictly inside the upload directory.
+  if (!filePath.startsWith(uploadDir + path.sep)) {
     return new NextResponse("Forbidden", { status: 403 });
   }
 
-  if (!fs.existsSync(filePath)) {
+  // Single stat() replaces the previous existsSync() + statSync() (2 → 1
+  // syscall). The try/catch also catches ENOENT, EACCES, ENAMETOOLONG, etc.
+  let stat: fs.Stats;
+  try {
+    stat = fs.statSync(filePath);
+  } catch {
     return new NextResponse("Not found", { status: 404 });
   }
 
-  const stat = fs.statSync(filePath);
+  // Guard against directory traversal that resolves to a directory
+  if (!stat.isFile()) {
+    return new NextResponse("Not found", { status: 404 });
+  }
+
+  // ── Content-Type ──────────────────────────────────────────────────────────
   const ext = path.extname(filePath).toLowerCase();
   const mimeMap: Record<string, string> = {
     ".mp4": "video/mp4",
@@ -33,35 +71,93 @@ export async function GET(
   };
   const contentType = mimeMap[ext] ?? "application/octet-stream";
 
-  // Support range requests so the HTML5 video player can seek
+  // ── Caching headers ───────────────────────────────────────────────────────
+  // ETag: stable because uploaded files are immutable — re-uploads produce
+  // a new UUID filename, so mtime and size never change for a given path.
+  const etag = `"${stat.size.toString(36)}-${stat.mtimeMs.toString(36)}"`;
+  const lastModified = stat.mtime.toUTCString();
+
+  const sharedHeaders = {
+    "Content-Type": contentType,
+    "Accept-Ranges": "bytes",
+    "Cache-Control": "public, max-age=3600, immutable",
+    "ETag": etag,
+    "Last-Modified": lastModified,
+  };
+
   const rangeHeader = req.headers.get("range");
 
+  // ── Range request path (RFC 7233) ─────────────────────────────────────────
   if (rangeHeader) {
-    const [startStr, endStr] = rangeHeader.replace("bytes=", "").split("-");
-    const start = parseInt(startStr, 10);
-    const end = endStr ? parseInt(endStr, 10) : stat.size - 1;
-    const chunkSize = end - start + 1;
+    // RFC 7233 §3.2 — If-Range: only honour Range if the representation is
+    // unchanged. If the validator doesn't match, fall through to a full 200.
+    const ifRange = req.headers.get("if-range");
+    const rangeIsValid = !ifRange || ifRange === etag || ifRange === lastModified;
 
-    const stream = fs.createReadStream(filePath, { start, end });
-    const nodeStream = stream as unknown as ReadableStream;
-
-    return new NextResponse(nodeStream, {
-      status: 206,
-      headers: {
-        "Content-Range": `bytes ${start}-${end}/${stat.size}`,
-        "Accept-Ranges": "bytes",
-        "Content-Length": String(chunkSize),
-        "Content-Type": contentType,
-      },
+    if (rangeIsValid) {
+      // Parse "bytes=<start>-<end>" with regex to handle surrounding whitespace
+      const rangeMatch = /bytes\s*=\s*(\d*)-(\d*)/i.exec(rangeHeader);
+      if (!rangeMatch) {
+        // Malformed Range header → 416 Range Not Satisfiable
+        return new NextResponse(null, {
+          status: 416,
+          headers: { ...sharedHeaders, "Content-Range": `bytes */${stat.size}` },
         });
       }
 
-  const stream = fs.createReadStream(filePath) as unknown as ReadableStream;
+      const start = rangeMatch[1] ? parseInt(rangeMatch[1], 10) : 0;
+
+      // RFC 7233 §2.1: start byte past EOF → 416
+      if (start >= stat.size) {
+        return new NextResponse(null, {
+          status: 416,
+          headers: { ...sharedHeaders, "Content-Range": `bytes */${stat.size}` },
+        });
+      }
+
+      // Cap end: honour explicit client requests but never exceed CHUNK_SIZE
+      // beyond start, and never past EOF.
+      const requestedEnd = rangeMatch[2] ? parseInt(rangeMatch[2], 10) : stat.size - 1;
+      const end = Math.min(requestedEnd, start + CHUNK_SIZE - 1, stat.size - 1);
+      const chunkSize = end - start + 1;
+
+      const stream = fs.createReadStream(filePath, {
+        start,
+        end,
+        highWaterMark: READ_HIGH_WATER_MARK,
+      }) as unknown as ReadableStream;
+
+      return new NextResponse(stream, {
+        status: 206,
+        headers: {
+          ...sharedHeaders,
+          "Content-Range": `bytes ${start}-${end}/${stat.size}`,
+          "Content-Length": String(chunkSize),
+        },
+      });
+    }
+    // If-Range mismatch: fall through to full-file response below
+  }
+
+  // ── Full-file response (no Range header, or If-Range mismatch) ────────────
+  // RFC 7232: 304 Not Modified applies only to full-file (non-range) requests
+  const ifNoneMatch = req.headers.get("if-none-match");
+  const ifModifiedSince = req.headers.get("if-modified-since");
+  if (
+    (ifNoneMatch && ifNoneMatch === etag) ||
+    (!ifNoneMatch && ifModifiedSince && new Date(ifModifiedSince) >= stat.mtime)
+  ) {
+    return new NextResponse(null, { status: 304 });
+  }
+
+  const stream = fs.createReadStream(filePath, {
+    highWaterMark: READ_HIGH_WATER_MARK,
+  }) as unknown as ReadableStream;
+
   return new NextResponse(stream, {
     headers: {
+      ...sharedHeaders,
       "Content-Length": String(stat.size),
-      "Content-Type": contentType,
-      "Accept-Ranges": "bytes",
     },
   });
 }

components/player/ReviewPlayer.tsx

@@ -81,6 +81,16 @@ export const ReviewPlayer = forwardRef<ReviewPlayerRef, ReviewPlayerProps>(
       setFps(fps);
     }, [fps, setFps]);
 
+    // Reset playback state when the source changes so the timeline and
+    // timecode don't briefly show the previous clip's values while the new
+    // video is loading its metadata.
+    useEffect(() => {
+      setCurrentFrame(0);
+      setCurrentTime(0);
+      setDuration(0);
+      setTotalFrames(0);
+    }, [videoUrl, setCurrentFrame, setCurrentTime, setDuration, setTotalFrames]);
+
     // ── Playback state sync ──────────────────────────────────────────────────
     const handleTimeUpdate = useCallback(() => {
       const video = videoRef.current;
@@ -269,7 +279,7 @@ export const ReviewPlayer = forwardRef<ReviewPlayerRef, ReviewPlayerProps>(
             onLoadedMetadata={handleLoadedMetadata}
             onPlay={handlePlay}
             onPause={handlePause}
-            preload="metadata"
+            preload="auto"
             playsInline
           />