We are using Redis at Hashnode. If you turn on disk persistence, Redis will save the data on disk periodically. And in case of a restart, it'll read the data from disk and populate the cache. If you are working with JSON, you can simply stringify the object and store it in a key. Another option is to use hmset and hmget to directly store and retrieve hashes.
Since you are using Node.js, node_redis is a great library for interacting with Redis.