Galaxya

embeddable peer 2 peer service discovery and configuration service

• Galaxya helps one process or machine discover another, using gossip
• Galaxya helps one process prepare for discovery of processes that do not exist yet.

Example

start galaxya from command line (starts on port 25120)

seed

npm install -g galaxya

> galaxya

service1.js

var galaxya = require('galaxya')({ seeds: [ '127.0.0.1:25120' ] })
galaxya.start(function () {
    galaxya.registerService({
        port: 12345,
        name: 'foo',
        version: '1.0.0',
        data: {
            my: 'service',
            data: 1
        }
    })
})

service2.js

var galaxya = require('galaxya')({ port: 25121, seeds: [ '127.0.0.1:25120' ] }})
galaxya.start(function () {
    galaxya.registerService({
        port: 1234,
        name: 'foo',
        version: '0.0.6',
        data: {
            my: 'service',
            data: 1
        }
    })
})

client.js

var galaxya = require('galaxya')({port: 25123, seeds: [ '127.0.0.1:25122' ]})

galaxya.start(function () {

    var services = galaxya.lookupService('foo', '0.0.5')

    //services might be
    // [
    //      { port: 12345, name: 'foo', version: '1.0.0', data: { my: 'service', data: 1 }},
    //      { port: 12345, name: 'foo', version: '0.0.6', data: { my: 'service', data: 1 }}
    // ]

    // discover new foo services (in the future!)
    var discovery = galaxya.discoverService('foo')

    discovery.on('available', function (service) {
        // notify on all foo services
    })

    discovery.on('available', '0.0.3', function (service) {
        // notify on versions equal or higher than 0.0.3
        service.on('fail', function () {    })
        service.on('alive', function () { })
    })

    // this also works
    galaxya.discoverService('foo', function(err, service) {
        // will be fired EACH TIME a 'foo' service will be discovered
        // as this might be unconventional, in the future we might change this so it will be called 
        // only in the first discovery.
    })
})

namespacing

    // service1.js
    galaxya.registerService({
        name: 'foo/bar/moo',
        port: 1234
    })

    galaxya.registerService({
        name: 'foo/bar',
        port: 1234
    })

    // serviceClient.js
    var discovery = galaxya.discoverService('foo/bar')

    discovery.on('available', function(service) {
        // fires twice, once for foo/bar and once for foo/bar/moo
    })

Availability

    // serviceClient.js
    var discovery = galaxya.discoverService('foo/bar')

    discovery.on('available', function(service) {
        service.on('fail', function () {

        })

        service.on('alive', function () {

        })
    })

TODO

• document the 1 to many mapping between gossiper to services topology
• add auto network space assignment
• is trie really the right structure for the underlying index?
• allow for gossiper per machine architecture
• discoverService callback, first time only or always?
• add consensus algorithm