sock-channels

Small wrapper around sockjs that handels objects and arrays and adds multiplexing

Usage no npm install needed!

<script type="module">
  import sockChannels from 'https://cdn.skypack.dev/sock-channels';
</script>

README

Build Status Dependency Status rethink.js js-standard-style

sock-channels

Allows to create channels on top of socket connection based on sock.js.

Installation

npm install sock-channels

Basic usage

Usage is really simple. Just create an sock.js connection on client and server side and create a channel with the same socket connection and the same prefix.

Establish a connection on the client

var SockjsClient = require('sockjs-client')
var createClientChannel = require('sock-channels')

clientRootChannel = createClientChannel(new SockjsClient('/ws'))

On the server side simply do

var http = require('http')
var sockjsServer = require('sockjs')
var createServerChannel = require('sock-channels')

socketServer = sockjsServer.createServer()
var httpServer = http.createServer()
socketServer.installHandlers(httpServer, {prefix: '/ws'})
httpServer.listen(9999, '0.0.0.0')
serverRootChannel = createServerChannel(socketServer)

In both cases, there has to be an active Sock.js connection on the /ws route.

You know have one root channel to communitcate through. Objects are serialized to JSON.

//client -> server
clientRootChannel.write({my: 'things', are: [1,2]});

//server -> all clients (broadcast)
serverRootChannel.write({my: 'things', are: [1,2]});

//server -> specific client
serverRootChannel.onConnect.push(function (connection) {
  serverRootChannel.write({my: 'things', are: [1,2]}, { only: connection });
  // ... or
  connection.write(serverRootChannel, {my: 'things', are: [1,2]});
})

//server -> all but specific client
serverRootChannel.onConnect.push(function (connection) {
  serverRootChannel.write({my: 'things', are: [1,2]}, { exclude: connection });
})

Listening on data also is really easy

//client
channel.onData.push(function(data) {
  data.my == 'things' // true
});

//server
channel.onData.push(function(data, connection) {
  data.my == 'things' // true
}
// ... or
channel.onData.push(function(data, channel) {
  data.my == 'things' // true
  channel.id == 'root' // true
}

Note that you there are also two possibilities to listen on data on server side, one is channel centric the other connection related. You always get the other object as parameter in the callback function.

This hopefully offers great flexibility in using this module.

Channel multiplexing

It's the same on client and on server side:

var fooCh = existingChannel.sub('foo');
var barCh = fooCh.sub('bar');

This can be done to any depth you want. Internaly sock-channels store the channels by concatenating the channel id's together:

fooCh.id == 'root:foo'; //true
barCh.id == 'root:foo:bar'; //true

All messages are marked according the channel id, but you don't have to care about this.

Events

Events are done with a minimal event-observer lib called smoke-signal

you can attach to events by calling once or push. Detach with pause.

On the client channel there are the following events

  • channel.onOpen: calles if the connection to the server is established
  • channel.onData: calles if there is some incomming data, data is first argument

On the server channel there are the following events

  • channel.onConnect: calles if the connection to the client is established, connection is first argument
  • channel.onData: calles if there is some incomming data, data is first argument, connection is second

On the server connection there are the following events

  • channel.onData: calles if there is some incomming data, data is first * argument, channel is second

License

(The MIT License)

Copyright (c) 2016 Stephan Hoyer ste.hoyer@gmail.com

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.