Redis driver instanceof check fails across ioredis majors and silently falls back to 127.0.0.1:6379

[sakib412]

Summary

RedisDriver and redisBusDriver decide whether config.connection is an existing client via instanceof IoRedis || instanceof IoRedisCluster (redis.ts#L38, #L63). That check uses bentocache's own ioredis copy. When the host app resolves a different ioredis major, the check is false for a perfectly valid client and the driver silently does new IoRedis(connection) with a Redis instance as the options object. ioredis ignores the unknown shape and connects to 127.0.0.1:6379.

This just happened via @adonisjs/cache@2.1.0 (passes redis.connection(name).ioConnection) after @adonisjs/redis@10.0.1 bumped ioredis to ^6.0.0 while bentocache still peers on ^5.3.2. pnpm installs both 5.11.1 and 6.0.0, and production ended up with:

[ioredis] Unhandled error event: Error: connect ECONNREFUSED 127.0.0.1:6379

repeated every ~2s indefinitely (ioredis 5 default retry, since the app's retryStrategy never reached the stray client).

Suggestions

1. Duck-type instead of instanceof: e.g. typeof connection.duplicate === 'function' && typeof connection.sendCommand === 'function' (or check for status/options), so any ioredis major works when handed an instance.
2. Widen the peer range to ^5.3.2 || ^6.0.0 once verified against RESP3 defaults.
3. At minimum, throw when config.connection looks like a client but fails the instanceof check, instead of falling back to localhost. A loud failure would have made this a 5 minute diagnosis rather than a production incident.

Same pattern exists in @boringnode/bus RedisTransport (options instanceof Redis), though @adonisjs/cache passes plain options to the bus so that path was not hit here.

Related upstream report on adonisjs/redis: adonisjs/redis#77

Env

• bentocache 1.6.1, @adonisjs/cache 2.1.0, @adonisjs/redis 10.0.1 (ioredis 6.0.0) alongside bentocache's ioredis 5.11.1
• pnpm 10, Node 24