Connecting to elastiCache cluster with node.js

Question

I am struggling to find node examples in connecting to my Elasticache cluster via node.js lambda using node-redis.

```
const { createCluster }= require('redis');
const redisClient = require('redis');

function createRedisClient() {
    const client = createCluster({
        rootNodes: [
            {
                host: process.env.redis_endpoint // This is the configuration endpoint given for the cluster plus port
            }
        ]      
    });
    return client;
}
```
I get an invalid protocol when I try to connect.  I have tried adding 3 of the shard endpoints to the above code with the same result.  I have tried just creating a redis client( rather than cluster) and get the same results.  How is this done?

Answer

Hello,

as per [node-redis source code](https://github.com/redis/node-redis/blob/c473c5fcce3009dac6819ab50044f0dfed014041/packages/client/lib/client/index.ts#L130) , the error is thrown when `ParseURL()` finds an invalid configuration:

```
if (protocol === 'rediss:') {
	(parsed.socket as RedisTlsSocketOptions).tls = true;
} else if (protocol !== 'redis:') {
	throw new TypeError('Invalid protocol');
}
```

I could not find "host" as a valid parameter for [CreateCluster().rootNodes configuration](https://github.com/redis/node-redis/blob/master/docs/clustering.md#createcluster-configuration).

You probably want to replace `host` by `url` and make sure that `process.env.redis_endpoint` expands to a valid URL like:

> `redis[s]://[[username][:password]@][host][:port][/db-number]`

Example:
- no in-transit encryption
```
const client = createCluster({
    rootNodes: [
      {
        url: 'redis://Elasticache_Cluster_Endpoint_here:6379'
      }
    ]
  });
```

- in-transit encryption without authentication:
```
const client = createCluster({
    rootNodes: [
      {
        url: 'rediss://Elasticache_Cluster_Endpoint_here:6379'
      }
    ]
  });

```

- in-transit encryption and RBAC/ACL authentication:
```
const client = createCluster({
    rootNodes: [
      {
        url: 'rediss://user_name:password@Elasticache_Cluster_Endpoint_here:6379'
      }
    ]
  });

```

Connecting to elastiCache cluster with node.js

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