I use Redis in my Next.js project. It works good but it seems in built time (next build) it tries to connect to Redis and since Redis connection is not available it throws this error:

Collecting page data  ..[ioredis] Unhandled error event: Error: connect ECONNREFUSED 127.0.0.1:6379
    at TCPConnectWrap.afterConnect [as oncomplete] (node:net:1495:16)

My Redis singleton client is:

import Redis from 'ioredis';

export const redis: Redis =
  global.redis ||
  new Redis({
    host: process.env.REDIS_HOST || 'localhost',
    port: Number.parseInt(process.env.REDIS_PORT ?? '6379', 10),
    db: Number.parseInt(process.env.REDIS_DB ?? '6', 10),
    keyPrefix: process.env.REDIS_PREFIX ?? ''
  });

/** This prevents creating multiple instance of redis client in development mode */
if (process.env.NODE_ENV === 'development') {
  global.redis = redis;
}

As Redis connection shouldn’t be used in build time. How can I fix this?