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I am programming in Express.js, running within an AWS Elastic Beanstalk instance, trying to connect to an AWS ElastiCache instance with Redis. I get this error:

web: Error connecting to Redis Error: connect ECONNREFUSED 127.0.0.1:6379
web: at TCPConnectWrap.afterConnect [as oncomplete] (node:net:1494:16) {
web: errno: -111,
web: code: 'ECONNREFUSED',
web: syscall: 'connect',
web: address: '127.0.0.1',
web: port: 6379
web: }

What is interesting is that I can PING Redis within the same program (and I get back a PONG), but I cannot connect using "createClient".

Here is the relevant code:

import * as dotenv from "dotenv";
dotenv.config();
import express from "express";
import { createClient } from "redis";
import net from "net";

const app = express();

console.log("NOTE: Pre createClient");
console.log("*** HOST = ", process.env.REDIS_HOST);
console.log("*** PORT = ", process.env.REDIS_PORT);

//----------------------------------------
// Pinging Redis Server
//----------------------------------------

const client = new net.Socket();
client.setTimeout(5000);
client.connect(process.env.REDIS_PORT, process.env.REDIS_HOST, () => {
    client.write("PING\r\n");
});
client.on("data", (data) => {
    console.log("PING TEST: Reply: ", data.toString());
    client.destroy();
});
client.on("error", (err) => {
    console.error("PING TEST: Error connecting to Redis server:", err);
    client.destroy();
});
client.on("timeout", () => {
    console.error("PING TEST: Connection timed out.");
    client.destroy();
});

//----------------------------------------
// Connecting to Redis
//----------------------------------------

let redisClient = createClient({
    host: process.env.REDIS_HOST,
    port: process.env.REDIS_PORT || 6379,
});
redisClient.on("connect", () => {
    console.log("Connected to Redis");
});
redisClient.on("error", (error) => {
    console.error("Error connecting to Redis", error);
});

console.log("NOTE: Pre connect");
console.log("*** redisClient = ", JSON.stringify(redisClient));

try {
    await redisClient.connect();
} catch (error) {
    console.error("Error connecting to Redis CLIENT:", err);
}
console.log("NOTE: Post connect");

Above the error listed above, I get this output

web:> *<name-of-app>*@1.0.0 start
web: > node index.js
web: NOTE: Pre createClient
web: *** HOST =  aia-elasti-redis.*<6 digits>*.clustercfg.euw1.cache.amazonaws.com
web: *** PORT =  6379
web: NOTE: Pre connect
web: *** redisClient =  {"_events":{},"_eventsCount":2,"bf":{},"cms":{},"cf":{},"tDigest":{},"topK":{},"graph":{},"json":{},"ft":{},"ts":{}}
web: PING TEST: Reply:  +PONG

Because I get back the "PONG", I know that: (a) the Redis Server is running, and (b) I can reach it from the Elastic Beanstalk server using the AWS Configuration Endpoint.

There is no username or password set up. So, I cannot think of any other way to format the createClient

I find it odd that I do not see the "NOTE: Post connect" even though the redisClient.connect() is within a try/ catch.

EricF
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  • Are you *sure* you're [passing in the arguments correctly](https://docs.redis.com/latest/rs/references/client_references/client_nodejs/)? – tadman Apr 30 '23 at 22:41
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    That worked! Thanks. I implemented the TLS format instead of the ACL format. – EricF May 01 '23 at 00:06

1 Answers1

2

Two solutions:

const client = redis.createClient({
    socket: {
        host: '<hostname>',
        port: '<port>'
    }
});

And:

createClient({
    url: 'redis://alice:foobared@awesome.redis.server:6380'
});

See: https://redis.io/docs/clients/nodejs/

EricF
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