faas.js

// Connection info, a URI with this shape:
// [redis[s]:]//[[user][:password@]][host][:port][/db-number][?db=db-number[&password=bar[&option=value]]]
const REDIS_URI = process.env.REDIS_URI;

// Redis client library
const redis = require('redis');

// Client instance
const r = redis.createClient(REDIS_URI);

// Promisify get and set
const { promisify } = require('util');
const setAsync = promisify(r.set).bind(r);
const getAsync = promisify(r.get).bind(r);

// This is the lambda function:
exports.handler =  async function(event, context) {
  console.log("EVENT: \n" + JSON.stringify(event, null, 2))
  
  // Set a key
  await setAsync("mykey", "hello world");
  
  // Return the value to the caller
  return getAsync("mykey");
}