How to properly connect to Redis from node app

I’m trying to use Redis as a cache for my node app.

My app looks as follows:

–redisClient.ts–

import redis = require('redis');

const client = redis.createClient({url: 'myRedisURL'});
export default client;

–myRoute.ts–

import client from 'redisClient';
...
let redisValue: string;
await client.connect();
redisValue = await client.get(key);
if(!redisValue) redisValue = await some_external_api_call(key); 
client.set(key, value, {EX: 3600 * 24});

Done this way, I get the error "Socket already opened" on RedisSocket.connect.
If I omit the line async client.connect(); then I get the error "The client is closed" at Commander._RedisClient_sendCommand.

Any clues to what I’m doing wrong would be much appreciated.