pubsub.js

pubsub.js

Dependency free JavaScript pubsub implementation with wildcards, inheritance and multisubscriptions.

Working smoothly both on frontend and backend side.

Read documentation, check tests file, be inspired and feel free to use it and/or contribute.

Web page

NPM pubsub.js link

Features

• Currently it is the most advanced dependency-free pub/sub library on npm
• Very fast
• Easy to understand
• Dependency free = using native JavaScript code
• Configurable link
• Works on server and browser side smoothly link
• Event inheritance link
• Wildcards publish wildcard subscribe wildcard
• subscribeOnce method link
• Multiple subscriptions link
• Possibility to make new instances of pubsub with private namespaces scope link
• Possibility to publish async events link
• Possibility to define context for all callbacks by providing pubsub|newInstance "context" param link
• Possibility to define context for each callback link
• Controll under event bubbling depth
• Works with require.js library
• Written with TDD
• Compiled + gzipped weighs only 1kB, less than 320 lines of code
• Works also on IE 6+

Installation

• download from Github
• npm: npm install pubsub.js
• bower: bower install pubsub-advanced

Default pubsub.js configuration:

	separator : '/' // defined namespace separator
	context         // has dynamic value - when not defined it will be always reference to used callback in subscribe method
	recurrent : false // defines inheritance of publish event
	async 	  : false // if true - publish events will be asynchronous
	log       : false // set to true will log unsubscribed namespaces to which You publish event

Using pubsub inside node.js

	var pubsub = require('pubsub.js');

	pubsub.subscribe('hello/world', function(text) {
		console.log(text);
	});
	pubsub.publish('hello/world', ['my text']);

Examples

Basic example

	//subscribe to 'hello/world' namespace
	pubsub.subscribe('hello/world', function() {
		console.log('hello world!');
	});
	//publish event on 'hello/world' namespace
	pubsub.publish('hello/world');
	//prints "hello world" inside console

Publish with param

	//subscribe to 'hello/world' namespace
	pubsub.subscribe('hello/world', function(data) {
		console.log(data);
	});
	//publish event on 'hello/world' namespace
	pubsub.publish('hello/world', ['hello!']); // second parameter is an array of arguments
	//prints "hello!" inside console

Unsubscribe

	//subscribe to 'hello/world' namespace
	var subscription = pubsub.subscribe('hello/world', function() {
		console.log('hello world!');
	});
	//publish event on 'hello/world' namespace
	pubsub.publish('hello/world');
	//prints "hello world" inside console

	//unsubscribe
	pubsub.unsubscribe(subscription);
	//publish event on 'hello/world' namespace
	pubsub.publish('hello/world');
	//nothing happen - we've previously unsubscribed that subscription

Changing default configuration

Browser

Before pubsub script loader - make global variable named "pubsub" with your default configuration

	pubsub = {
		separator : '.'
		context : referenceToContext
	}

After pubsub load - use it with your configuration, pubsub.js will replace that previous "pubsub" global variable with its own instance

	//subscribe to 'hello.world' namespace
	var subscription = pubsub.subscribe('hello.world', function() {
		console.log('hello world!');
	});
	//publish event on 'hello.world' namespace
	pubsub.publish('hello.world');
	//prints "hello world" inside console

	//unsubscribe
	pubsub.unsubscribe(subscription);
	//publish event on 'hello.world' namespace
	pubsub.publish('hello.world');
	//nothing happen - we've previously unsubscribed that subscription

Node.js

Before pubsub require execution - set global.pubsubConfig variable

	global.pubsubConfig = {
		separator : '.'
	}

After pubsub load, it'll have your configuration as in browser example

Event inheritance

	//subscribe to 'hello' namespace
	var subscription = pubsub.subscribe('hello', function() {
		console.log('hello world!');
	});
	//publish event on 'hello/world' namespace
	pubsub.publish('hello/world', [], {
		recurrent : true
	});
	//prints "hello world" inside console
	//first event goes to "hello" namespace
	//then it tries to execute on "hello/world" but nothing is listening on it

Method: subscribeOnce

	var iterator = 0;
	var data = null;

	pubsub.subscribeOnce('hello/world', function(param) {
		data = param;
		iterator++;
	});
	pubsub.publish('hello/world', ['hello']);
	pubsub.publish('hello/world', ['world']);
	console.log(iterator); //1
	console.log(data); //'hello'

Publish wildcard "*"

	var number = 0;

	//subscribe to "hello/world" namespace
	pubsub.subscribe('hello/world', function() {
		number++;
	});
	//subscribe to "hello/earth" namespace
	pubsub.subscribe('hello/earth', function() {
		number++;
	});
	//subscribe to "hello/galaxy" namespace
	pubsub.subscribe('hello/galaxy', function() {
		number++;
	});
	//subscribe to "hello/world/inner" namespace
	pubsub.subscribe('hello/world/inner', function() {
		number++;
	});

	pubsub.publish('hello/*');
	//hello/* executes:
	//	hello/world, hello/earth, hello/galaxy
	//	namespace, hello/world/inner is not executed
	//
	//	"*" goes only one namespace deeper
	console.log(number); //3

Subscribe wildcard "*"

	var number = 0;

	var subscription = pubsub.subscribe('hello/*/world', function() {
		number += 1;
	});

	pubsub.publish('hello'); // won't handle
	pubsub.publish('hello/my'); // won't handle
	pubsub.publish('hello/great/galaxy'); // won't handle

	pubsub.publish('hello/my/world'); // handles
	pubsub.publish('hello/huge/world'); // handles
	pubsub.publish('hello/great/world'); // handles

	console.log(number); // 3

Multiple subscriptions

many namespaces, one callback

	var number = 0;

	var subscription = pubsub.subscribe(['hello/world', 'goodbye/world'], function() {
		number++;
	});

	pubsub.publish('hello/world');
	console.log(number); //1
	pubsub.publish('goodbye/world');
	console.log(number); //2
	pubsub.unsubscribe(subscription);

	pubsub.publish('hello/world');
	console.log(number); //2
	pubsub.publish('goodbye/world');
	console.log(number); //2

one namespace, many callbacks

	var number1 = 0;
	var number2 = 0;

	var subscription = pubsub.subscribe('hello/world', [function() {
		number1++;
	}, function() {
		number2 += 2;
	}]);

	pubsub.publish('hello/world');
	console.log(number1 + ',' + number2); //1,2
	pubsub.unsubscribe(subscription);

	pubsub.publish('hello/world');
	console.log(number1 + ',' + number2); //2,4

many namespaces, many callbacks

	var number1 = 0;
	var number2 = 0;

	var subscription = pubsub.subscribe(['hello/world', 'goodbye/world'], [function() {
		number1++;
	}, function() {
		number2 += 2;
	}]);

	pubsub.publish('hello/world');
	console.log(number1 + ',' + number2); //1,2
	pubsub.publish('goodbye/world');
	console.log(number1 + ',' + number2); //2,4
	pubsub.unsubscribe(subscription);

	pubsub.publish('hello/world');
	console.log(number1 + ',' + number2); //2,4
	pubsub.publish('goodbye/world');
	console.log(number1 + ',' + number2); //2,4

###making new instances with own namespaces scope

	var number1 = 0;
	var number2 = 0;

	var privatePubsub = pubsub.newInstance();

	pubsub.subscribe('hello/world', function() {
		number1++;
	});

	privatePubsub.subscribe('hello/world', function() {
		number2++;
	});

	pubsub.publish('hello/world');
	console.log(number1 + ',' + number2); //1,0

	privatePubsub.publish('hello/world');
	console.log(number1 + ',' + number2); //1,1

making new instances with own context

	var contextArgument = ["object"];
	var privatePubsub = pubsub.newInstance({
		context : contextArgument
	});

	privatePubsub.subscribe('hello/context', function() {
		var that = this;

		console.log(that === contextArgument); //true
	});
	privatePubsub.publish('hello/context');

###Using pubsub asynchronously

	var number1 = 0;

	var asyncPubsub = pubsub.newInstance({
		async : true
	});

	asyncPubsub.subscribeOnce('hello/world', function() {
		number1++;
		console.log(number1); //2
	});

	asyncPubsub.publish('hello/world'); // asynchronous call to 'hello/world'

	number1++;
	console.log(number1); //1

###Using context param in subscribe method

	var contextArgument = ["object"];
	var privatePubsub = pubsub.newInstance();

	function callbackFirst() {
		var that = this;

		console.log(that === callbackFirst); // true
	}
	function callbackSecond() {
		var that = this;

		console.log(that === contextArgument); // true
	}

	var privateSubscribtion1 = privatePubsub.subscribe('hello/context', callbackFirst);
	var privateSubscribtion2 = privatePubsub.subscribe('hello/that', callbackSecond, {
		context : contextArgument
	});

Changelog

• v1.5.2
  • Fixed IE11 cross frames communication (isArray)
• v1.5.1
  • Fix "context" option for subscribeOnce
  • .eslintrc style guide added + code stylistic fixes
• v1.5.0
  • Fix issue #8 - "context" option, new test cases
• v1.4.3
  • Fix issue #7 - "recurrent" option, new test cases
• v1.4.2
  • Documentation changes
• v1.4.1
  • Travis integration
• v1.4.0
  • Added subscription wildcard "*"
• v1.3.1
  • Fixed problem with "window reference error" in node.js environment
• v1.3.0
  • Changed the way of using context parameter in subscribe method - API changes to subscribe method!
• v1.2.0
  • Changed the way of using event inheritance - API changes to publish method!
  • Added possibility to use "publish" asynchronously
• v1.1.0
  • reworked core
  • changed the way of setting own config
  • implemented "newInstance" method
• v1.0.6
  • Fixed bug with unsubscription - subscription during publish of the same namespace (test case 3)
• v1.0.5
  • Added multisubscription possibilities
• v1.0.4
  • Added subscribeOnce method
• v1.0.3
  • Changed scope binding in pubsub
• v1.0.2
  • Publish wildcard "*" added
• v1.0.1
  • Improved performance - about 350% on chrome, 20% on firefox
• v1.0.0
  • Every basic test passing

License

MIT