Redis command to get all available keys on Redis Cluster?

Question

I am using this

redisManager.redisClient.keys('*example*', function (err, keys) {
})

But it only gives keys from only one of the redis cluster. How can I get keys from all cluster?

Respiratory

Shouldn't all nodes of a cluster share the same data and give the same result? Or are we talking multiple clusters here? – Karlin

node-redis-cluster can do this. You can check it here: npmjs.com/package/node-redis-cluster – Kadner

@john Siu, all nodes giving separate data – Respiratory

can you show how you are setting the cluster value ? – Aramaic

Or you can use redisClient.zrange("example", 0, -1, function(err, replies) { – Aramaic

Which package are you using? – Protectionist

Answer 1

You can't get keys for all nodes using a single command. You have to get keys for all nodes and merge them. Reference - https://github.com/antirez/redis/issues/1962

You can do something like.

var redis = require('redis');

redisConfig = new Array(
    {"port": 1234, "host": "192.168.1.2"},
    {"port": 5678, "host": "192.168.1.3"}
);

keys    = new Array();
allKeys = new Array();

for(i = 0; i < redisConfig.length; i++){
    redisClient = redis.createClient(redisConfig[i].port, redisConfig[i].host);    
      keys[i] = redisClient.keys('*example*', function (err, keys) {
      allkeys = [...new Set([...allKeys ,...keys[i]])];
    })
}

Nellynelms

@Albin Mathew Does it help? – Nellynelms

keys command is slower in redis and not recommend. Warning: consider KEYS as a command that should only be used in production environments with extreme care. It may ruin performance when it is executed against large databases. This command is intended for debugging and special operations, such as changing your keyspace layout. Don't use KEYS in your regular application code. If you're looking for a way to find keys in a subset of your keyspace, consider using SCAN or sets. – Earphone

Answer 2

Have you tried using the node-redisscan package? It allows you to use SCAN commands on Redis clusters.

You'd have to collect each matching key with the callback. Here's how you'd do it (directly lifted from the README file) -

var redisScan = require('redisscan');
var redis = require('redis').createClient();

redisScan({
    redis: redis,
    each_callback: function (type, key, subKey, value, done) {
        console.log(type, key, subKey, value);
        done();
    },
    done_callback: function (err) {
        if (err) throw err;
        redis.quit();
    }
});

Heterocercal

Answer 3

You can use this code inorder to find keys from all cluster. Please refer to link for more info.

    var RedisCluster = require('node-redis-cluster').RedisCluster;

    var rcluster = RedisCluster.create([
        { port: 6379, host: '10.0.0.1' },
        { port: 6379, host: '10.0.0.2' },
        { port: 6379, host: '10.0.0.3' },
    ]);
    rcluster.execAll('keys', ['*'], function(err, results) {
    /* results will be
    {
        '10.0.0.1:6379': [ // keys],
        '10.0.0.2:6379': [ // keys],
        '10.0.0.3:6379': [ // keys]
    }
    */
    });

Jalisajalisco

Answer 4

Keys command not recommended to be used in productions mode.

From redis docs Warning: consider KEYS as a command that should only be used in production environments with extreme care. It may ruin performance when it is executed against large databases. This command is intended for debugging and special operations, such as changing your keyspace layout. Don't use KEYS in your regular application code. If you're looking for a way to find keys in a subset of your keyspace, consider using SCAN or sets.

Use scanStream Instead

            redisConnection = redisConnectionObject;

            const slaves = redisConnection.nodes("slave");

            config.info('number of slaves', slaves.length)


            let keys = [];
            let slavePromises = [];

            slaves.forEach((slave) => {
                let slaveCreate = new Promise((resolve) => {

                    const stream = slave.scanStream({
                        match: prefix
                    });

                    stream.on("data", (resultKeys) => {
                        keys = [...keys, ...resultKeys];
                    });
                    stream.on("end", () => {
                        resolve();
                    });
                });

                slavePromises.push(slaveCreate);
            });

            Promise.all(slavePromises).then(([slaveOneData, slaveTwoData]) => {

                keys = _.uniq(keys);

                resolveOne(keys);
            });

Earphone

Answer 5

I converted this from my C# code. You need to query across all servers and build your list of keys.

const Redis = require('ioredis');

async function getKeyList(servers, pattern) {
    const keyList = [];

    for (const server of servers) {
        if (!server.isConnected) continue;

        const keys = await server.keys(pattern);

        if (keys.length === 0) continue;

        keyList.push(...keys);
    }

    return keyList;
}

// Example usage:
const servers = [
    new Redis({ host: 'server1', port: 6379 }),
    new Redis({ host: 'server2', port: 6379 }),
    // Add more server configurations as needed
];

const pattern = 'your_pattern_here';

getKeyList(servers, pattern)
    .then((keyList) => {
        console.log('Keys:', keyList);
    })
    .catch((error) => {
        console.error('Error:', error);
    });

Rebeckarebeka

Answer 6

Run command $ npm install redis to install redis.

var redis = require('redis'),
    client = redis.createClient();

client.keys('*', function (err, keys) {
  if (err) return console.log(err);

  for(var i = 0, len = keys.length; i < len; i++) {
    console.log(keys[i]);
  }
});  

Inherent

this is a solution for a standalone redis server, not for a redis cluster as the question states. – Aorist