looking for efficient way to use redis with node.js

Question

I've coded up some examples for a chat room using redis and node.js, but before I continue on this path, I want to know if this is the best way to be doing it:

var redis = require('redis')
, cache = redis.createClient(cfg.redis_port, cfg.redis_host)


function getUsers(cb){
    cache.select(cfg.redis_db, function(err, status){
        cache.get('chat.users', function(err, data){
            var users = data && JSON.parse(data) || [];

            c.log('get users', users);
            cb(users);
        });
    });
}

function addUser(user, cb){
    getUsers(function(users){
        users.push(user);

        cache.select(cfg.redis_db, function(err, status){
            cache.set('chat.users', JSON.stringify(users), function(){
                c.log('cache set', arguments);

                c.log('add user', user, users);
                cb(users);
            });
        });
    });
}

function removeUser(user, cb){
    getUsers(function(users){
        users = _.reject(users, function(val){
            return user.nick === val.nick;
        });

        cache.select(cfg.redis_db, function(err, status){
            cache.set('chat.users', JSON.stringify(users), function(){
                c.log('cache set', arguments);

                c.log('remove user', user, users);

                cb(users);
            });
        });
    });
}

The reason I ask is it seems rather cumbersome to have to do cache.select all over the place then cache.get.

Nate · Accepted Answer · 2013-12-12 04:52:05Z

1

In Redis, once the DB is selected, it remains selected until another SELECT is issued. And because the Node Redis client queues commands that are issued before the client is ready, you can do something like this:

var redis = require('redis')
, cache = redis.createClient(cfg.redis_port, cfg.redis_host);

cache.select(cfg.redis_db);

// the rest of your code

It doesn’t look very Node-ish, but it works and is shown (as a comment; easy to miss) in one of the examples on the node-redis home page.

answered Dec 12, 2013 at 4:52

Nate

19.1k9 gold badges51 silver badges54 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

looking for efficient way to use redis with node.js

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related