ataraxia

ataraxia

Mesh networking with peer-to-peer messaging for NodeJS. Ataraxia connects different NodeJS instances together and allows messages to be passed between these instances. Some instances may act as routers for other instances to create a mesh network.

For support for services with RPC and events see ataraxia-services.

Installation

npm install ataraxia

Also install one or more transports:

• ataraxia-local provides a machine-local transport
• ataraxia-tcp provides a TCP-based transport with local network discovery
• ataraxia-ws-client and ataraxia-ws-server for websockets

Example with TCP transport

const Network = require('ataraxia');
const TCPTransport = require('ataraxia-tcp');

const net = new Network({ name: 'name-of-your-app-or-network' });
net.addTransport(new TCPTransport());

net.on('node:available', node => {
  console.log('A new node is available:', node.id);
  node.send('hello');
});

net.on('message', msg => {
  console.log('A message was received', msg.type, 'with data', msg.data, 'from', msg.returnPath.id);
});

net.start()
  .then(...)
  .catch(...);

Example with machine-local transport and TCP transport

This example creates a network where instances on the same machine connect to each other locally first and then elects one instance to handle connections to other machines on the same network.

const Network = require('ataraxia');
const LocalTransport = require('ataraxia-local');
const TCPTransport = require('ataraxia-tcp');

const net = new Network({ name: 'name-of-your-app-or-network' });

const local = new LocalTransport();
local.on('leader', () => {
  /*
   * The leader event is emitted when this instance becomes the leader
   * of the machine-local network. This instance will now handle
   * connections to other machines in the network.
   */
  net.addTransport(new TCPTransport());
});
net.addTransport(local);

net.start()
  .then(...)
  .catch(...);

API

Network

• new Network(options) - create a new network using the given options. Options may be:
  • name - Required. The name of the network, should be short and describe the app or library.
  • endpoint - Request that the local node is an endpoint that should not perform routing.
• start() - start the network and its transports
• stop() - stop the network and its transports
• addTransport(transport) - add a transport that should be used
• on('node:available', node => ...) - a node has been found and messages can now be sent and received to/from it
• on('node:unavailable', node => ...) - a node is no longer available
• on('message', ({ returnPath, type, data }) => ...) - a message has been received from a node

Node

• id - get the id of the node
• available - get if the node is reachable
• on('unavailable', () => ...) - node is no longer available
• send(type, data) - send a message of the given type with the specified data to the node
• on('message', ({ returnPath, type, data }) => ...) - a message has been received from this node