feat(server): redis session storage and ttl helper

Made-with: Cursor

server/utils/session-redis.ts

@@ -0,0 +1,37 @@
+import { getRedis } from "./redis";
+import { sessionTtlSeconds } from "./session-ttl";
+
+export type SessionPayload = {
+  userId: number;
+  sessionVersion: number;
+  createdAt: string;
+};
+
+const sessionKey = (id: string) => `sess:${id}`;
+
+export async function createSession(
+  sessionId: string,
+  payload: SessionPayload,
+): Promise<void> {
+  const redis = getRedis();
+  const ttl = sessionTtlSeconds();
+  await redis.set(sessionKey(sessionId), JSON.stringify(payload), "EX", ttl);
+}
+
+export async function readSession(
+  sessionId: string,
+): Promise<SessionPayload | null> {
+  const redis = getRedis();
+  const raw = await redis.get(sessionKey(sessionId));
+  if (!raw) return null;
+  try {
+    return JSON.parse(raw) as SessionPayload;
+  } catch {
+    return null;
+  }
+}
+
+export async function deleteSession(sessionId: string): Promise<void> {
+  const redis = getRedis();
+  await redis.del(sessionKey(sessionId));
+}

server/utils/session-ttl.ts

@@ -0,0 +1,5 @@
+export function sessionTtlSeconds(): number {
+  const raw = process.env.SESSION_TTL_SECONDS;
+  const n = raw ? Number(raw) : NaN;
+  return Number.isFinite(n) && n > 0 ? n : 604800;
+}

test/unit/session-ttl.test.ts

@@ -0,0 +1,17 @@
+import { describe, expect, it, beforeEach } from "bun:test";
+import { sessionTtlSeconds } from "../../server/utils/session-ttl";
+
+describe("sessionTtlSeconds", () => {
+  beforeEach(() => {
+    delete process.env.SESSION_TTL_SECONDS;
+  });
+
+  it("defaults to 7d", () => {
+    expect(sessionTtlSeconds()).toBe(604800);
+  });
+
+  it("respects env", () => {
+    process.env.SESSION_TTL_SECONDS = "120";
+    expect(sessionTtlSeconds()).toBe(120);
+  });
+});