fix: improve file lock fallback

- Remove retries from sync lock (not supported)
- Handle Windows path for tmp directory
- Ignore ENOENT when releasing
- Add fallback unit tests

Author: jlin53882

src/redis-lock.ts

@@ -8,7 +8,16 @@
 import Redis from 'ioredis';
 import path from 'node:path';
 import fs from 'node:fs';
-import proper-lockfile from 'proper-lockfile';
+
+// 用 lazy import 避免 ESM 問題
+let properLockfile: any = null;
+
+async function loadProperLockfile(): Promise<any> {
+  if (!properLockfile) {
+    properLockfile = await import('proper-lockfile');
+  }
+  return properLockfile;
+}
 
 // 生成唯一 token
 function generateToken(): string {
@@ -135,7 +144,9 @@ export class RedisLockManager {
    * 建立 file lock（Redis 不可用時的 fallback）
    */
   private createFileLock(key: string, ttl?: number): () => Promise<void> {
-    const lockPath = path.join('/tmp', `.memory-lock-${key}.lock`);
+    // Windows tmp 目錄
+    const tmpDir = process.platform === 'win32' ? 'C:\\tmp' : '/tmp';
+    const lockPath = path.join(tmpDir, `.memory-lock-${key}.lock`);
     const lockTTL = (ttl || this.defaultTTL) / 1000; // proper-lockfile 用秒
 
     // 確保目錄存在
@@ -144,14 +155,10 @@ export class RedisLockManager {
       fs.mkdirSync(dir, { recursive: true });
     }
 
-    // 同步取得 file lock
+    // 同步取得 file lock（不支援 retries）
     try {
-      proper_lockfile.lockSync(lockPath, {
-        retries: {
-          retries: 10,
-          minTimeout: 1000,
-          maxTimeout: 30000,
-        },
+      const lockfile = require('proper-lockfile');
+      lockfile.lockSync(lockPath, {
         stale: lockTTL,
       });
       console.log(`[RedisLock] Acquired file lock for ${key}`);
@@ -162,10 +169,14 @@ export class RedisLockManager {
     // 回傳 release function
     return async () => {
       try {
-        await proper_lockfile.unlock(lockPath);
+        const lockfile = require('proper-lockfile');
+        await lockfile.unlock(lockPath);
         console.log(`[RedisLock] Released file lock for ${key}`);
       } catch (err) {
-        console.warn(`[RedisLock] Failed to release file lock: ${err}`);
+        // 忽略 ENOENT（檔案不存在）
+        if (!err.message.includes('ENOENT')) {
+          console.warn(`[RedisLock] Failed to release file lock: ${err}`);
+        }
       }
     };
   }

test/redis-lock-fallback.test.mjs

@@ -0,0 +1,87 @@
+// test/redis-lock-fallback.test.mjs
+/**
+ * Redis Lock Fallback 測試
+ * 
+ * 測試當 Redis 不可用時，是否會正確 fallback 到 file lock
+ */
+
+import { describe, it } from "node:test";
+import assert from "node:assert/strict";
+import { mkdtempSync, rmSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import jitiFactory from "jiti";
+
+const jiti = jitiFactory(import.meta.url, { interopDefault: true });
+const { RedisLockManager } = jiti("../src/redis-lock.ts");
+
+describe("Redis Lock Fallback", () => {
+  // 測試 1：Redis 不可用時使用 file lock
+  it("should fallback to file lock when Redis unavailable", async () => {
+    // 故意用一個不會有 Redis 的 URL
+    const manager = new RedisLockManager({
+      redisUrl: 'redis://localhost:9999', // 不存在的 Redis
+      ttl: 5000,
+      maxWait: 5000,
+    });
+    
+    const release = await manager.acquire("fallback-test-key");
+    
+    // 應該成功取得 lock（file lock fallback）
+    assert.ok(release, "Should return a release function");
+    
+    // 執行 release
+    await release();
+    
+    console.log("[Fallback test] Successfully used file lock fallback");
+  });
+
+  // 測試 2：多次取得不同 key 的 lock
+  it("should handle multiple locks with fallback", async () => {
+    const manager = new RedisLockManager({
+      redisUrl: 'redis://localhost:9999',
+      ttl: 3000,
+    });
+    
+    const locks = [];
+    for (let i = 0; i < 3; i++) {
+      const release = await manager.acquire(`fallback-multi-${i}`);
+      locks.push(release);
+    }
+    
+    // 應該成功取得 3 個 lock
+    assert.strictEqual(locks.length, 3, "Should acquire 3 locks");
+    
+    // 全部 release
+    for (const release of locks) {
+      await release();
+    }
+    
+    console.log("[Fallback test] Multiple locks handled successfully");
+  });
+
+  // 測試 3：file lock 的 TTL 行為
+  it("should respect TTL in file lock fallback", async () => {
+    const shortTTL = 1000; // 1 秒
+    
+    const manager = new RedisLockManager({
+      redisUrl: 'redis://localhost:9999',
+      ttl: shortTTL,
+    });
+    
+    const release = await manager.acquire("fallback-ttl-test");
+    
+    // 等待 TTL 過期
+    await new Promise(r => setTimeout(r, shortTTL + 500));
+    
+    // 應該可以再次取得同一個 key（因為 TTL 過期了）
+    const release2 = await manager.acquire("fallback-ttl-test");
+    
+    await release();
+    await release2();
+    
+    console.log("[Fallback test] TTL respected in file lock");
+  });
+});
+
+console.log("=== Redis Lock Fallback Tests ===");