cabal-core

cabal-core

Core database, replication, swarming, and chat APIs for cabal.

Usage

npm install cabal-core

API

var Cabal = require('cabal-node')

var cabal = Cabal([storage][, key][, opts])

Create a cabal p2p database using storage storage, which must be either a string (filepath to directory on disk) or an instance of random-access-storage.

key is a hex string of the key, without any prefixes (like cabal://).

If this is a new database, key can be omitted and will be generated.

You can pass opts.db as a levelup or leveldown instance to use persistent storage for indexing instead of using memory. For example:

var level = require('level')
var cabal = Cabal(storage, key, { db: level('/tmp/bot.db') })

cabal.getLocalKey(cb)

Returns the local user's key (as a hex string).

var ds = cabal.replicate()

Creates a new, live replication stream. This duplex stream can be piped into any transport expressed as a node stream (tcp, websockets, udp, utp, etc).

cabal.ready(cb)

Call cb() when the underlying indexes are caught up.

Channels

cabal.channels.get(function (error, channels) {})

Retrieve a list of all channel names that exist in this cabal.

cabal.channels.events.on('add', function (channel) {})

Emitted when a new channel is added to the cabal.

Messages

var rs = cabal.messages.read(channel, opts)

Returns a readable stream of messages (most recent first) from a channel.

Pass opts.limit to set a maximum number of messages to read.

cabal.messages.events.on('message', fn)

Calls fn with every new message that arrives, regardless of channel.

cabal.messages.events.on(channel, fn)

Calls fn with every new message that arrives in channel.

Network

var swarm = require('cabal-core/swarm')

cabal.swarm(cb)

Joins the P2P swarm for a cabal. This seeks out peers who are also part of this cabal by various means (internet, local network), connects to them, and replicates cabal messages between them.

The returned object is an instance of discovery-swarm.

cabal.on('peer-added', function (key) {})

Emitted when you connect to a peer. key is a hex string of their public key.

cabal.on('peer-dropped', function (key) {})

Emitted when you lose a connection to a peer. key is a hex string of their public key.

Publishing

cabal.publish(message, opts, cb)

Publish message to your feed. message must have a type field set. If not, it defaults to chat/text. In general, a message is formatted as

{
  type: 'chat/text',
  content: {
    text: 'hello world',
    channel: 'cabal-dev'
  }
}

A timestamp field is set automatically with the current system time.

type is an unrestricted field: you can make up new message types and clients will happily ignore them until someone implements support for them. Well documented types include

chat/text

{
  type: 'chat/text',
  content: {
    text: 'whatever the user wants to say',
    channel: 'some channel name. if it didnt exist before, it does now!'
  }
}

License

AGPLv3

Changelog

[7.0.1] - 2019-08-04

Changed

• Use the same cabal key consistently (@hackergrrl)