Node.js and Redis: async GET/SET

redis.js

const redis = require("redis")
const { promisify } = require("util")
const {
  redis: { clientOptions, expire },
} = require("../config/get-config")

let client

/**
 * Asynchronous version of `client.get`
 * @param {string} key a Redis key
 * @returns {Promise} the corresponding value of `key` or null if it doesn't exist
 */
function get(key) {
  if (!client) {
    client = redis.createClient(clientOptions)
  }

  const getAsync = promisify(client.get).bind(client)
  return getAsync(key)
}

/**
 * Sets a value inside Redis. Expiration is taken from the main configuration
 * @param {string} key Redis key
 * @param {string} val Redis value
 * @returns {Promise} a reply string
 * @see https://redis.io/commands/set
 * @see https://redis.io/topics/protocol#simple-string-reply
 */
function set(key, val) {
  if (!client) {
    client = redis.createClient(clientOptions)
  }
  const setAsync = promisify(client.set).bind(client)
  return setAsync(key, val, "EX", expire)
}

module.exports = {
  get,
  set,
}