cabal-core

cabal-core

Core database, replication, 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.

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

cabal.getLocalKey(cb)

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

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

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!'
  }
}

swarm

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

swarm(cabal)

Join the P2P swarm for a cabal, start connecting to peers and replicating messages.

Returns a discovery-swarm.

License

AGPLv3

Changelog

[4.0.1] - 2019-05-08

Added

• Add an option to set the .maxFeeds option of hypercore-protocol when replicating (#33) (@nikolaiwarner)

Fixed

• Allow options for messages.read() to take priority over defaults (#29) (@telamon)
• Fix error propagation bug in topics view (#30) (@telamon)