Realtime Service

Status: Usable, but a work in progress. Feedback encouraged!

An open standard describing a mix of client and server-side code designed to communicate over a persistent connection. This will usually be a WebSocket connection, but any Realtime Transport module is compatible.

Realtime Services are designed to be very easy to understand, write, test and share on npm.

Each service is defined in the simplest possible way: as a plain old JavaScript object. Here's a simple example:

var service = {
  client: function(client) {
    client.onmessage = function(msg) {
      console.log('Message in from server:', msg);
    }
  },
 
  server: function(server) {
    setInterval(function(){
      server.broadcast('Hello!');  
    }, 1000);
  }
}

Examples Services

(all alpha quality for now)

rts-rpc
rts-pubsub
rts-livereload

Features

• super-simple: services are just JavaScript objects
• client and server code can expose APIs to be called by the app
• easy to write tests
• the realtime-service-client can run in a browser or separate node process
• each service has it's own directory to store files (e.g. model definitions)
• efficiently handles callbacks, even for non-JSON messages
• services can optionally use Sessions (provided by the server)
• server is notified when a client connect/disconnect (allowing cleanup)
• services can send JavaScript assets to the browser
• optionally handles JSON encoding/decoding for you
• provides a standard logging API
• ultra light weight client-side code (for sending to browser)

Realtime Services do not care about:

• the underlying transport layer (abstracted away by Realtime Transport)
• how code is delivered to the browser (left to the framework or app to implement)

Implementations

Realtime Services are currently implemented in Prism, the realtime server component of SocketStream 0.4.

As other frameworks / toolkits implement them, they will be listed here.

Contents

Realtime Services consist of

1. This - the server-side library
2. The realtime-service-client module
3. The Realtime Server Spec (Coming soon!)

API

Coming soon!

History

Realtime Services are the evolution of an idea called "Request Responders" which first appeared in SocketStream 0.3. Despite a horribly clunky API, the idea proved to be popular with third-party modules for Backbone and Angular soon appearing.

Realtime Services will be one of the key features of SocketStream 0.4. However, I hope by ensuring the spec is a simple as possible (with minimal dependencies), other frameworks will support Realtime Services in the future. The ultimate goal is an ecosystem of reusable components using 100% standard npm packages.

Licence

MIT