rtc-mesh

NOTE: From version 0.5 onwards rtc-mesh is now an rtc-quickconnect plugin (which is heaps better and cleaner).

The rtc-mesh module provides a way of sharing data between clients using scuttlebutt.

Simple Example

var quickconnect = require('rtc-quickconnect');
var mesh = require('rtc-mesh');

// initialise the connection
var qc = quickconnect('http://rtc.io/switchboard', {
  room: 'meshdemo-simple'
});

// create the model
var model = mesh(qc);

// report data change events
model.on('change', function(key, value) {
  console.log('captured change key: "' + key + '" set to ', value);
});

model.set('lastjoin', Date.now());

Using Scuttlebutt Subclasses

In the case that you would like to use one of the Scuttlebutt subclasses, this can be done quite easily be providing a model instance in the model option in the opts argument. Here's an example using CRDT:

var quickconnect = require('rtc-quickconnect');
var mesh = require('rtc-mesh');
var Doc = require('crdt').Doc;
var uuid = require('uuid');

// initialise the connection
var qc = quickconnect('http://rtc.io/switchboard', {
  room: 'meshdemo-crdt'
});

// create the model
var model = mesh(qc, { model: new Doc() });

model.on('add', function(row) {
  console.log('new row created: ', row);
});

model.add({ id: uuid.v4(), name: 'Fred' });

Synchronizing Multiple Datasets

It's also possible to create invoke multiple meshes on a single data channel using custom channel names (by default the a channel is created with the name of mesh).

var quickconnect = require('rtc-quickconnect');
var mesh = require('rtc-mesh');

// initialise the connection
var qc = quickconnect('http://rtc.io/switchboard', {
  room: 'meshdemo-multichannel'
});

// create the models
var modelA = mesh(qc, { channelName: 'm1' });
var modelB = mesh(qc, { channelName: 'm2' });

// report data change events
modelA.on('change', function(key, value) {
  console.log('captured change for item in a: ', arguments);
});

modelB.on('change', function(key, value) {
  console.log('captured change for item in b: ', arguments);
})

// update some keys
modelA.set('lastjoin', Date.now());
modelB.set('lastRandom', (Math.random() * 10000) | 0);

Reference

mesh

mesh(qc, opts?) => Model

As displayed in the examples, the mesh function expects to be passed a quickconnect created signaller. Using this object, it will create a data channel that will be responsible for sharing scuttlebutt model information with peers.

In addition to the functions exposed by a scuttlebutt Model, the following helpers have also been added:

retrieve

retrieve(key, callback)

Get the value of the specified key and pass the result back through the provided callback (node error first style). If the value is already available in the local Model, then the callback will be triggered immediately. If not, the callback will be triggered once the value has been set in the local Model.

License(s)

Apache 2.0

Copyright 2014 National ICT Australia Limited (NICTA)

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

 http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.