In this article we are going to add caching to our Node.js application using Redis.

We will install the recommended client for node.js as mentioned on the official Redis page.

npm install redis --save

Next we shall create our client connection

var redis = require('redis')

var hostname = '127.0.0.1'
var port = '6379'
var password = 'yourpassword'

var client = redis.createClient(port,hostname,{no_ready_check: true})

client.auth(password)

client.on('connect', function() {
        console.log('Client was connected')
})

The password provided on auth will be stashed and used on every connect.

Let’s see some basic actions:

SMEMBERS actions

client.sadd('aset', 2)
client.sadd('aset', 1)
client.sadd('aset', 5)

client.smembers('aset',function(err,reply) {
    console.log(reply)
})

Get and Set actions

client.set('akey', "This is the value")

client.get('akey',function(err,reply) {
    console.log(reply)
})

Hash value actions

client.hset('hashone', 'fieldone', 'some value');
client.hset('hashone', 'fieldtwo', 'another value');

var hash = 'hashone'

client.hkeys(hash, function (err, fields) {

    fields.forEach(function(field,i) {

        console.log('The field is '+field)

        client.hget(hash,field,function (err, value) {
            console.log('The content is '+value)
        })
    })

});

List actions

client.rpush(['mylist', 'firstItem', 'secondItem'], function(err, listsize) {
    console.log(listsize)
});

client.lrange('mylist',0,-1,function(err,values) {
    console.log(values)
})

client.lpop('mylist',function(err,value) {
    console.log('Got '+value)
})

 Conclusion

The Redis client for Node.js is pretty straightforward and easy to get started.

Keep in mind that one connection is adequate. Redis is single threaded therefore there is no need for opening multiple connections.

You can refer to the github page for more examples and usage showcases.