An very basic example usage of k-bucket to route requests on a dht

dht.js

var KBucket = require('k-bucket');
var crypto = require('crypto');

// Number of nodes
var NUM_NODES = 5;
var NUM_ITEMS = 100;

// Make the routing table
var router = new KBucket();

// Make nodes in the k-bucket
for (var i = 0; i < NUM_NODES; i++) {
	router.add(createNode(i));
}

// Make some items and store them
for (var i = 0; i < NUM_ITEMS; i++) {
	saveItem('item' + i);
}

// Get some items and describe them
describeItem('item1');
describeItem('item123');
describeItem('item345');
describeItem('item567');

// Desribe a node and the data in it
describeNode('Bucket0');

// A node is a little in memory k/v store
function createNode(i) {
	var name = 'Bucket' + i;
	return {
		id: new Buffer(sha1(name)),
		name: name,
		_data: {},
		length: 0,
		put: function(hash, d) {
			if (!this._data[hash]) this.length++;
			this._data[hash] = d;
		},
		get: function(hash) {
			return this._data[hash];
		}
	};
}

// To save an item, pick the closest node, and put it there
function saveItem(item) {
	var hash = sha1(item);
	whichNode(hash).put(hash, item);
}

// Get an item is to find the closes node and get from it
function getItem(item) {
	var hash = sha1(item);
	return whichNode(hash).get(hash);
}

// Use the k-bucket router to find the closes node to an item
function whichNode(hash) {
	return router.closest({
		id: new Buffer(hash)
	}, 1)[0];
}

// helper to sha1 things
function sha1(d) {
	return crypto.createHash('sha1').update(d).digest('hex');
};

function describeItem(item) {
	var hash = sha1(item);
	var node = whichNode(hash);

	console.log('========================');
	console.log('Item Conent: ', node.get(hash));
	console.log('Node Name: ', node.name);
	console.log('Item Hash: ', hash);
}

function describeNode(name) {
	var hash = sha1(name);
	var node = whichNode(hash);
	var items = [];
	for (var i in node._data) {
		items.push(node._data[i]);
	}

	console.log('========================');
	console.log('Node Name: ', node.name);
	console.log('Items Stored In Node: ', node.length);
	console.log('Items In Node: \n', items);
}

out.txt

> $ node index.js
========================
Item Conent:  item1
Node Name:  Bucket3
Item Hash:  4e702d8dacb758a70499bd7a1cd4259087b743df
========================
Item Conent:  undefined
Node Name:  Bucket3
Item Hash:  41857183a56ba0402914ad20df39a464879fd484
========================
Item Conent:  undefined
Node Name:  Bucket0
Item Hash:  7c54e0c538c60d07c52a04f477048e86722e7f09
========================
Item Conent:  undefined
Node Name:  Bucket1
Item Hash:  10f0bb1c0607d715e313f558769a4bc3b432e0b9
========================
Node Name:  Bucket0
Items Stored In Node:  36
Items In Node:
 [ 'item2',
  'item3',
  'item8',
  'item11',
  'item17',
  'item19',
  'item20',
  'item22',
  'item26',
  'item27',
  'item29',
  'item31',
  'item33',
  'item36',
  'item37',
  'item38',
  'item40',
  'item41',
  'item42',
  'item44',
  'item50',
  'item52',
  'item58',
  'item59',
  'item61',
  'item69',
  'item73',
  'item75',
  'item77',
  'item78',
  'item79',
  'item81',
  'item84',
  'item89',
  'item91',
  'item92' ]