Merge 4fd803fb7d48372cffe2adb9f4916327ed090bbe into 6b4c24c2e55b5b4013277bd799525086f6a0c40f

src/agents/pi-embedded-runner/session-manager-cache.test.ts

@@ -0,0 +1,97 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+
+// The module reads process.env and Date.now() at call time, so we
+// dynamically re-import after setting up fakes / env vars.
+type Mod = typeof import("./session-manager-cache.js");
+
+describe("session-manager-cache", () => {
+  let mod: Mod;
+
+  beforeEach(async () => {
+    vi.useFakeTimers();
+    // Ensure caching is enabled (default TTL > 0).
+    delete process.env.OPENCLAW_SESSION_MANAGER_CACHE_TTL_MS;
+    vi.resetModules();
+    mod = await import("./session-manager-cache.js");
+  });
+
+  afterEach(() => {
+    vi.useRealTimers();
+    vi.restoreAllMocks();
+    delete process.env.OPENCLAW_SESSION_MANAGER_CACHE_TTL_MS;
+  });
+
+  // ── Max-size cap ──────────────────────────────────────────────
+
+  it("enforces max-size cap of 500 entries", () => {
+    for (let i = 0; i < 510; i++) {
+      mod.trackSessionManagerAccess(`/sessions/s-${i}.json`);
+    }
+    expect(mod.sessionManagerCacheSize()).toBeLessThanOrEqual(500);
+  });
+
+  // ── LRU ordering via delete+set ───────────────────────────────
+
+  it("re-access refreshes LRU position — recently used entry survives eviction", () => {
+    // Fill cache to 499 entries (s-0 … s-498).
+    for (let i = 0; i < 499; i++) {
+      mod.trackSessionManagerAccess(`/sessions/s-${i}.json`);
+    }
+    expect(mod.sessionManagerCacheSize()).toBe(499);
+
+    // Re-access s-0 → moves it to the end of insertion order.
+    mod.trackSessionManagerAccess("/sessions/s-0.json");
+    expect(mod.sessionManagerCacheSize()).toBe(499); // no growth, same key
+
+    // Add two new entries to push past 500.
+    mod.trackSessionManagerAccess("/sessions/s-500.json"); // size → 500
+    mod.trackSessionManagerAccess("/sessions/s-501.json"); // evicts oldest (s-1)
+
+    // s-0 was refreshed so it should still be present (500 entries, s-0 near end).
+    // The evicted entry should be s-1 (oldest after s-0 was refreshed).
+    expect(mod.sessionManagerCacheSize()).toBe(500);
+
+    // After eviction, the refreshed entry (s-0) must survive, oldest untouched (s-1) must be evicted
+    expect(mod.isSessionManagerCached("/sessions/s-0.json")).toBe(true);
+    expect(mod.isSessionManagerCached("/sessions/s-1.json")).toBe(false);
+  });
+
+  // ── Lazy TTL eviction ─────────────────────────────────────────
+
+  it("lazy TTL eviction removes expired entry on cache check", async () => {
+    // Insert an entry directly.
+    mod.trackSessionManagerAccess("/sessions/a.json");
+    expect(mod.sessionManagerCacheSize()).toBe(1);
+
+    // Advance time past the 45 s default TTL.
+    vi.advanceTimersByTime(46_000);
+
+    // prewarmSessionFile calls isSessionManagerCached internally, which
+    // should now delete the stale entry and return false.  The subsequent
+    // fs.open will fail (file doesn't exist) so the entry is NOT re-added.
+    await mod.prewarmSessionFile("/sessions/a.json");
+    expect(mod.sessionManagerCacheSize()).toBe(0); // expired entry was evicted
+  });
+
+  // ── clearSessionManagerCache ──────────────────────────────────
+
+  it("clearSessionManagerCache empties the cache", () => {
+    mod.trackSessionManagerAccess("/sessions/a.json");
+    mod.trackSessionManagerAccess("/sessions/b.json");
+    expect(mod.sessionManagerCacheSize()).toBe(2);
+
+    mod.clearSessionManagerCache();
+    expect(mod.sessionManagerCacheSize()).toBe(0);
+  });
+
+  // ── Disabled cache (TTL=0) ────────────────────────────────────
+
+  it("skips tracking when cache is disabled via TTL=0", async () => {
+    process.env.OPENCLAW_SESSION_MANAGER_CACHE_TTL_MS = "0";
+    vi.resetModules();
+    const disabled = await import("./session-manager-cache.js");
+
+    disabled.trackSessionManagerAccess("/sessions/a.json");
+    expect(disabled.sessionManagerCacheSize()).toBe(0);
+  });
+});

src/agents/pi-embedded-runner/session-manager-cache.ts

@@ -9,6 +9,9 @@ type SessionManagerCacheEntry = {
 
 const SESSION_MANAGER_CACHE = new Map<string, SessionManagerCacheEntry>();
 const DEFAULT_SESSION_MANAGER_TTL_MS = 45_000; // 45 seconds
+// Safety-net cap. Working set is far smaller (entries live ≤45 s);
+// env override is intentionally not exposed — 500 >> realistic working set.
+const SESSION_MANAGER_CACHE_MAX_SIZE = 500;
 
 function getSessionManagerTtl(): number {
   return resolveCacheTtlMs({
@@ -25,6 +28,20 @@ export function trackSessionManagerAccess(sessionFile: string): void {
   if (!isSessionManagerCacheEnabled()) {
     return;
   }
+  // Refresh insertion order for existing keys so FIFO eviction is LRU-like.
+  // Map.set() on an existing key does NOT update insertion order (MDN), so
+  // we delete first to move it to the end.
+  if (SESSION_MANAGER_CACHE.has(sessionFile)) {
+    SESSION_MANAGER_CACHE.delete(sessionFile);
+  }
+  // Evict oldest entry when the cache is at its size limit.
+  // Map iteration order is insertion-order, so the first key is the oldest.
+  if (SESSION_MANAGER_CACHE.size >= SESSION_MANAGER_CACHE_MAX_SIZE) {
+    const oldest = SESSION_MANAGER_CACHE.keys().next();
+    if (!oldest.done) {
+      SESSION_MANAGER_CACHE.delete(oldest.value);
+    }
+  }
   const now = Date.now();
   SESSION_MANAGER_CACHE.set(sessionFile, {
     sessionFile,
@@ -32,7 +49,11 @@ export function trackSessionManagerAccess(sessionFile: string): void {
   });
 }
 
-function isSessionManagerCached(sessionFile: string): boolean {
+/**
+ * Check whether a session file is present and non-expired in the cache.
+ * @internal Visible for testing only.
+ */
+export function isSessionManagerCached(sessionFile: string): boolean {
   if (!isSessionManagerCacheEnabled()) {
     return false;
   }
@@ -42,7 +63,11 @@ function isSessionManagerCached(sessionFile: string): boolean {
   }
   const now = Date.now();
   const ttl = getSessionManagerTtl();
-  return now - entry.loadedAt <= ttl;
+  if (now - entry.loadedAt > ttl) {
+    SESSION_MANAGER_CACHE.delete(sessionFile);
+    return false;
+  }
+  return true;
 }
 
 export async function prewarmSessionFile(sessionFile: string): Promise<void> {
@@ -67,3 +92,18 @@ export async function prewarmSessionFile(sessionFile: string): Promise<void> {
     // File doesn't exist yet, SessionManager will create it
   }
 }
+
+/**
+ * Clear all cached entries.  Exported for tests and graceful-shutdown hooks.
+ */
+export function clearSessionManagerCache(): void {
+  SESSION_MANAGER_CACHE.clear();
+}
+
+/**
+ * Return the current number of entries in the cache.
+ * @internal Visible for testing only.
+ */
+export function sessionManagerCacheSize(): number {
+  return SESSION_MANAGER_CACHE.size;
+}