`RedisKvStore.set()` rejects any TTL that is not a whole number of seconds

[heeoneie]

RedisKvStore.set() passes options.ttl.total("second") straight to Redis SETEX, which requires a whole number of seconds. Any Temporal.Duration that is not an exact number of seconds is rejected by the server, so the write fails instead of storing the value with a rounded expiry.

This is reachable from application code: KvStoreSetOptions.ttl is public API and accepts any Temporal.Duration. It also became easier to hit in 2.4, where FederationOptions.publicKeyTtl and FederationOptions.httpMessageSignaturesSpecTtl let an application choose the cache lifetimes directly (#1027). Fedify's own defaults are all whole seconds, so nothing in the library trips it today.

Environment

• @fedify/redis 2.4.0 (main, commit 621958b)
• Deno 2.9.5, macOS 26.6.2 (aarch64)
• Redis 7 (redis:7-alpine in Docker)

Steps to reproduce

import { RedisKvStore } from "@fedify/redis/kv";
import { Redis } from "ioredis";

const store = new RedisKvStore(new Redis("redis://127.0.0.1:6379"));

await store.set(["k"], "v", { ttl: Temporal.Duration.from({ seconds: 1 }) });
await store.set(["k"], "v", { ttl: Temporal.Duration.from({ milliseconds: 500 }) });

Expected behavior

Both writes store the value. A sub-second TTL is expected to be normalized to the smallest expiry Redis can express rather than rejected.

Actual behavior

The first write succeeds. The second throws ReplyError: ERR value is not an integer or out of range.

The failure is not limited to sub-second durations. Every duration whose total is not an integer number of seconds fails the same way, and a zero duration fails with a different message:

TTL	ttl.total("second")	Result
1 second	1	stored
1500 milliseconds	1.5	ERR value is not an integer or out of range
500 milliseconds	0.5	ERR value is not an integer or out of range
1 millisecond	0.001	ERR value is not an integer or out of range
0	0	ERR invalid expire time in 'setex' command

Suggested fix

Normalize the argument to a positive integer before calling SETEX, so that a sub-second TTL becomes one second rather than an error. RedisKvStore has no cas() method, so set() is the only affected call site.

The adapter tests are gated on REDIS_URL and skip entirely without a live server, so a regression test for this needs a Redis instance to be meaningful.

AI usage disclosure

Per AI_POLICY.md: this report was AI-assisted. The problem was first raised by CodeRabbit on #1027; Claude Code drafted this report and ran the reproduction above against a local Redis 7 container. I checked the reproduction output and edited the text before filing.

[dahlia]

Confirmed that this reproduces in 2.0.x. Since this is a bug fix, please target 2.0-maintenance rather than main. We can then forward-port the fix to the newer branches.