Using riak-js

Count keys using key streaming

Setup:
npm install riak-js@latest

Usage:
node -e "require('riak-js').getClient({ host: 'hostname', port: 8098 }).count('bucket');"

(More here: https://github.com/frank06/riak-js)

Count keys using MR

var c = require('riak-js').getClient({ host: 'hostname', port: 8098 });
var mr = c.add('bucket').map(function m(v){return [1]}).reduce(function(v) { return [v.reduce(function(t, val) { return t + val; }, 0)]});
mr.run({timeout: 10000000});