Gun Constructor

Initialize a GUN database instance

Gun()

The Gun constructor initializes a new GUN database instance. You can create a local database or connect to peers for distributed synchronization.

Signature

var gun = Gun(options)

Parameters

options · object | string | array

Configuration options for the GUN instance. Can be an object with options, a peer URL string, or an array of peer URLs.

Show properties

peers · object | array | string

WebSocket or HTTP peers to synchronize with. Can be:

• A string URL: 'http://localhost:8765/gun'
• An array of URLs: ['ws://peer1.com/gun', 'ws://peer2.com/gun']
• An object mapping URLs to peer configurations

localStorage · boolean · default: "true"

Enable persistence to browser localStorage (browser only)

radisk · boolean

Enable RAD (Radix) disk storage adapter (Node.js)

uuid · function

Custom UUID generator function for creating unique node IDs

Return Value

Returns a GUN chain reference that can be used to read and write data.

Examples

Local Database

// Create a local-only database
var gun = Gun()

Single Peer

// Connect to a single peer
var gun = Gun('https://gunjs.herokuapp.com/gun')

// Or with options object
var gun = Gun({
  peers: 'https://gunjs.herokuapp.com/gun'
})

Multiple Peers

// Connect to multiple peers for redundancy
var gun = Gun([
  'https://peer1.example.com/gun',
  'https://peer2.example.com/gun',
  'wss://peer3.example.com/gun'
])

// Or with options object
var gun = Gun({
  peers: {
    'https://peer1.example.com/gun': {},
    'https://peer2.example.com/gun': {}
  },
  localStorage: true
})

Node.js with RAD Storage

var Gun = require('gun')
require('gun/lib/radix')
require('gun/lib/radisk')
require('gun/lib/store')
require('gun/lib/rindexed')

var gun = Gun({
  radisk: true,
  peers: ['http://localhost:8765/gun']
})

Implementation Details

From the source code (root.js:4-8):

function Gun(o){
  if(o instanceof Gun){ return (this._ = {$: this}).$ }
  if(!(this instanceof Gun)){ return new Gun(o) }
  return Gun.create(this._ = {$: this, opt: o});
}

The constructor:

1. Returns existing Gun instance if one is passed
2. Handles being called without new keyword
3. Initializes the internal state graph and event system
4. Sets up peer connections if specified

Notes

• GUN can be called with or without the new keyword
• All data is automatically synchronized across connected peers
• The constructor returns immediately; peer connections are established asynchronously
• Each Gun instance maintains an in-memory graph for fast reads