actor-emitter v0.1.8

ActorEmitter.js

Actoremitter.js is lightweight, independent, event emitter library which provides the observer pattern to javascript objects. It works on node.js and browser. It is a single .js file.

Why

This package is meant to be single instance, lightweight, async and scope-full event emitter, in order to provide communication between objects in different scopes. Binding on an event, maintains the worker scope, so they can continue to process the call in a non blocking way, with the next() method.

How to Use It

Actor emitter is single instance, so it listens and emits the same events all across your app.

var emitter = require('actor-emitter');

Check this websocket implementation with actor-emitter!

var WebSocketClient = require('websocket').client,
    emitter = require('actor-emitter'),
    client = new WebSocketClient();

var _connection = null;

var _wsSend = function (data) {

    try {

	    _connection.sendUTF(data);
	    console.log('-> ', data);

    } catch (err) {

	    console.error(err);
    }
}

var wsSend = function (data) {

    data = JSON.stringify(data);

    // declare next function call, with scope and non blocking
    emitter.next(_wsSend, data);
};

var wsOnMessage = function (data) {

    var key = data.header + ':' + data.action + (data.__code__ ? ':' + data.__code__ : '');

    emitter.trigger(key, data);
};

emitter.bind('socket:send', wsSend);

client.on('connectFailed', function(error) {

    console.log('Connect Error: ' + error.toString());
});

client.on('connect', function(connection) {

    console.log('WebSocket Client Connected');

    connection.on('error', function(error) {

	    console.log("Connection Error: " + error.toString());
    });

    connection.on('close', function() {

	    console.log('Connection Closed');
    });

    connection.on('message', function(message) {

	    if (message.type === 'utf8') {

	        console.log('<- ',  message.utf8Data);

	        emitter.next(wsOnMessage, JSON.parse(message.utf8Data));
	        emitter.trigger('socket:onmessage', JSON.parse(message.utf8Data));
	    }
    });

    _connection = connection;

    emitter.trigger('socket:onopen', connection);
});

client.connect('ws://someserver:8888/');

Its all assync, non-block and easy

Then, a worker should be like:

var emitter = require('actor-emitter'),
uuid     = require('node-uuid');

var worker = (function() {

    var _id;

    var onAuthenticationRequested = function (data) {

	    _id = uuid();
	    data._id = _id;
	    data.appKey = 'myapp';

        // send authentication request!
	    emitter.trigger('socket:send', data);
    };

    var requestUserPublicProfile = function () {

        var data = {
            header: 'myapp',
            action: 'user_get_public',
            nick: 'mynick'
        }

        emitter.trigger('socket.send', data);
    }

    emitter.bind('authentication:announce', onAuthenticationRequested);
    emitter.bind('authentication:announce:200', requestUserPublicProfile);
}

That example outputs something like this, assuming your server requests an authentication when connected

<-  {"action":"announce","header":"authentication"}
->  {"action":"announce","header":"authentication","_id":"77e5b21e-4494-481c-9591-621680bf0772","appKey":"myapp"}
<-  {"action":"announce","header":"authentication","__code__":200}
->  {"header":"myapp","action":"user_get_public","nick":"mynick"}
<-  ...

Thats it.

You need a single file "actoremitter.js". Include it in a webpage via the usual script tag.

<script src="actoremitter.js"></script>

To include it in a nodejs code isnt much harder

var aEmitter = require('actor-emitter.js')

MIT license. If you hit bugs, fill issues on github. Feel free to fork, modify and have fun with it :)