how to get notifiction if any changes/transaction happen in redis using nodejs

Question

I'am new to redis, i need help to get notify to my running server if any chages/transaction happen in redis(either from bakend also). The server which is in running state is created using node.js

Answer 1

Use the keyspace notification system. This uses the pub sub layer of redis

Steps : Set this parameter -notify-keyspace-events in redis.conf file By default its empty

This will enable capture of almost all DML events

Answer 2

I'm not sure about how to get notification about transaction, but here is a working code (using ioredis ) to get notified about any change in redis:

const redisClient = const redisClient = new Redis({
    host: 'localhost',
    port: 20000,
    lazyConnect: true, // because i will try to connect manually in the next line
    connectTimeout: 1000,
  })
await redisClient.connect()

// "AKE" === listen to all events of all redis-operations
await redisClient.config('SET', 'notify-keyspace-events', 'AKE')
await redisClient.psubscribe([`__key*__:*`])

redisClient.on(`pmessage`, (_pattern, redisKey, redisOpeation) => {
   const redisKey = redisKey.replace('__keyspace@0__:', '')
   if(redisKey === 'cool-redis-key' && redisOpeation === 'set'){
      console.log(`there was a "set" operation on "cool-redis-key" key`)
   }
})

Addtional info:

• example: https://stackoverflow.com/a/58687129/806963
• activate notifications: https://redis.io/topics/notifications