Duplcatet masters in RedisClusterSlots

[maciomen]

Description

Hi,

Thanks for the great work on this library!

I believe there might be an issue with how the masters array is populated in RedisClusterSlots. Consider this scenario:

Let’s assume I have a cluster with 300 max slots. If:

• node-1 owns slots 0–100 and 200–300

• node-2 owns slots 101–199

Then client.clusterSlots() will return three entries—two of them for node-1 with different from/to ranges.

When iterating over this result to populate the masters array, node-1 appears twice. This leads to the masters array having 3 entries instead of the expected 2 (i.e., node-1 and node-2 only once each).

Here’s a minimal example:

const cluster = createCluster(...);
await cluster.connect();
console.log(cluster.masters.length); // Outputs 3 instead of 2

Is this the expected behavior? Or should masters deduplicate entries by host/port or id?

Thanks in advance for clarifying!

Node.js Version

v22.14.0

Redis Server Version

7.2.4

Node Redis Version

4.7.1

Platform

Linux

Logs

[nkaradzhov]

Hi @maciomen, this issue is fixed in the latest version. There is the check.