fix: persist topic session files

src/config/cache-utils.ts

@@ -0,0 +1,27 @@
+import fs from "node:fs";
+
+export function resolveCacheTtlMs(params: {
+  envValue: string | undefined;
+  defaultTtlMs: number;
+}): number {
+  const { envValue, defaultTtlMs } = params;
+  if (envValue) {
+    const parsed = Number.parseInt(envValue, 10);
+    if (Number.isFinite(parsed) && parsed >= 0) {
+      return parsed;
+    }
+  }
+  return defaultTtlMs;
+}
+
+export function isCacheEnabled(ttlMs: number): boolean {
+  return ttlMs > 0;
+}
+
+export function getFileMtimeMs(filePath: string): number | undefined {
+  try {
+    return fs.statSync(filePath).mtimeMs;
+  } catch {
+    return undefined;
+  }
+}

src/config/sessions.ts

@@ -14,6 +14,11 @@ import {
   parseAgentSessionKey,
 } from "../routing/session-key.js";
 import { normalizeE164 } from "../utils.js";
+import {
+  getFileMtimeMs,
+  isCacheEnabled,
+  resolveCacheTtlMs,
+} from "./cache-utils.js";
 import { resolveStateDir } from "./paths.js";
 
 // ============================================================================
@@ -31,20 +36,14 @@ const SESSION_STORE_CACHE = new Map<string, SessionStoreCacheEntry>();
 const DEFAULT_SESSION_STORE_TTL_MS = 45_000; // 45 seconds (between 30-60s)
 
 function getSessionStoreTtl(): number {
-  // Allow runtime override via environment variable
-  const envTtl = process.env.CLAWDBOT_SESSION_CACHE_TTL_MS;
-  if (envTtl) {
-    const parsed = Number.parseInt(envTtl, 10);
-    if (Number.isFinite(parsed) && parsed >= 0) {
-      return parsed;
-    }
-  }
-  return DEFAULT_SESSION_STORE_TTL_MS;
+  return resolveCacheTtlMs({
+    envValue: process.env.CLAWDBOT_SESSION_CACHE_TTL_MS,
+    defaultTtlMs: DEFAULT_SESSION_STORE_TTL_MS,
+  });
 }
 
 function isSessionStoreCacheEnabled(): boolean {
-  const ttl = getSessionStoreTtl();
-  return ttl > 0;
+  return isCacheEnabled(getSessionStoreTtl());
 }
 
 function isSessionStoreCacheValid(entry: SessionStoreCacheEntry): boolean {
@@ -53,14 +52,6 @@ function isSessionStoreCacheValid(entry: SessionStoreCacheEntry): boolean {
   return now - entry.loadedAt <= ttl;
 }
 
-function getSessionStoreMtimeMs(storePath: string): number | undefined {
-  try {
-    return fs.statSync(storePath).mtimeMs;
-  } catch {
-    return undefined;
-  }
-}
-
 function invalidateSessionStoreCache(storePath: string): void {
   SESSION_STORE_CACHE.delete(storePath);
 }
@@ -199,12 +190,12 @@ export function resolveSessionTranscriptPath(
 export function resolveSessionFilePath(
   sessionId: string,
   entry?: SessionEntry,
-  opts?: { agentId?: string; topicId?: number },
+  opts?: { agentId?: string },
 ): string {
   const candidate = entry?.sessionFile?.trim();
   return candidate
     ? candidate
-    : resolveSessionTranscriptPath(sessionId, opts?.agentId, opts?.topicId);
+    : resolveSessionTranscriptPath(sessionId, opts?.agentId);
 }
 
 export function resolveStorePath(store?: string, opts?: { agentId?: string }) {
@@ -402,7 +393,7 @@ export function loadSessionStore(
   if (isSessionStoreCacheEnabled()) {
     const cached = SESSION_STORE_CACHE.get(storePath);
     if (cached && isSessionStoreCacheValid(cached)) {
-      const currentMtimeMs = getSessionStoreMtimeMs(storePath);
+      const currentMtimeMs = getFileMtimeMs(storePath);
       if (currentMtimeMs === cached.mtimeMs) {
         // Return a shallow copy to prevent external mutations affecting cache
         return { ...cached.store };
@@ -413,14 +404,14 @@ export function loadSessionStore(
 
   // Cache miss or disabled - load from disk
   let store: Record<string, SessionEntry> = {};
-  let mtimeMs = getSessionStoreMtimeMs(storePath);
+  let mtimeMs = getFileMtimeMs(storePath);
   try {
     const raw = fs.readFileSync(storePath, "utf-8");
     const parsed = JSON5.parse(raw);
     if (parsed && typeof parsed === "object") {
       store = parsed as Record<string, SessionEntry>;
     }
-    mtimeMs = getSessionStoreMtimeMs(storePath) ?? mtimeMs;
+    mtimeMs = getFileMtimeMs(storePath) ?? mtimeMs;
   } catch {
     // ignore missing/invalid store; we'll recreate it
   }