post/post.js

Emitter-like component to create safe cross origin communication

;(function(){

/**
 * Require the given path.
 *
 * @param {String} path
 * @return {Object} exports
 * @api public
 */

function require(path, parent, orig) {
  var resolved = require.resolve(path);

  // lookup failed
  if (null == resolved) {
    orig = orig || path;
    parent = parent || 'root';
    var err = new Error('Failed to require "' + orig + '" from "' + parent + '"');
    err.path = orig;
    err.parent = parent;
    err.require = true;
    throw err;
  }

  var module = require.modules[resolved];

  // perform real require()
  // by invoking the module's
  // registered function
  if (!module._resolving && !module.exports) {
    var mod = {};
    mod.exports = {};
    mod.client = mod.component = true;
    module._resolving = true;
    module.call(this, mod.exports, require.relative(resolved), mod);
    delete module._resolving;
    module.exports = mod.exports;
  }

  return module.exports;
}

/**
 * Registered modules.
 */

require.modules = {};

/**
 * Registered aliases.
 */

require.aliases = {};

/**
 * Resolve `path`.
 *
 * Lookup:
 *
 *   - PATH/index.js
 *   - PATH.js
 *   - PATH
 *
 * @param {String} path
 * @return {String} path or null
 * @api private
 */

require.resolve = function(path) {
  if (path.charAt(0) === '/') path = path.slice(1);

  var paths = [
    path,
    path + '.js',
    path + '.json',
    path + '/index.js',
    path + '/index.json'
  ];

  for (var i = 0; i < paths.length; i++) {
    var path = paths[i];
    if (require.modules.hasOwnProperty(path)) return path;
    if (require.aliases.hasOwnProperty(path)) return require.aliases[path];
  }
};

/**
 * Normalize `path` relative to the current path.
 *
 * @param {String} curr
 * @param {String} path
 * @return {String}
 * @api private
 */

require.normalize = function(curr, path) {
  var segs = [];

  if ('.' != path.charAt(0)) return path;

  curr = curr.split('/');
  path = path.split('/');

  for (var i = 0; i < path.length; ++i) {
    if ('..' == path[i]) {
      curr.pop();
    } else if ('.' != path[i] && '' != path[i]) {
      segs.push(path[i]);
    }
  }

  return curr.concat(segs).join('/');
};

/**
 * Register module at `path` with callback `definition`.
 *
 * @param {String} path
 * @param {Function} definition
 * @api private
 */

require.register = function(path, definition) {
  require.modules[path] = definition;
};

/**
 * Alias a module definition.
 *
 * @param {String} from
 * @param {String} to
 * @api private
 */

require.alias = function(from, to) {
  if (!require.modules.hasOwnProperty(from)) {
    throw new Error('Failed to alias "' + from + '", it does not exist');
  }
  require.aliases[to] = from;
};

/**
 * Return a require function relative to the `parent` path.
 *
 * @param {String} parent
 * @return {Function}
 * @api private
 */

require.relative = function(parent) {
  var p = require.normalize(parent, '..');

  /**
   * lastIndexOf helper.
   */

  function lastIndexOf(arr, obj) {
    var i = arr.length;
    while (i--) {
      if (arr[i] === obj) return i;
    }
    return -1;
  }

  /**
   * The relative require() itself.
   */

  function localRequire(path) {
    var resolved = localRequire.resolve(path);
    return require(resolved, parent, path);
  }

  /**
   * Resolve relative to the parent.
   */

  localRequire.resolve = function(path) {
    var c = path.charAt(0);
    if ('/' == c) return path.slice(1);
    if ('.' == c) return require.normalize(p, path);

    // resolve deps by returning
    // the dep in the nearest "deps"
    // directory
    var segs = parent.split('/');
    var i = lastIndexOf(segs, 'deps') + 1;
    if (!i) i = 0;
    path = segs.slice(0, i + 1).join('/') + '/deps/' + path;
    return path;
  };

  /**
   * Check if module is defined at `path`.
   */

  localRequire.exists = function(path) {
    return require.modules.hasOwnProperty(localRequire.resolve(path));
  };

  return localRequire;
};
require.register("component-emitter/index.js", function(exports, require, module){

/**
 * Expose `Emitter`.
 */

module.exports = Emitter;

/**
 * Initialize a new `Emitter`.
 *
 * @api public
 */

function Emitter(obj) {
  if (obj) return mixin(obj);
};

/**
 * Mixin the emitter properties.
 *
 * @param {Object} obj
 * @return {Object}
 * @api private
 */

function mixin(obj) {
  for (var key in Emitter.prototype) {
    obj[key] = Emitter.prototype[key];
  }
  return obj;
}

/**
 * Listen on the given `event` with `fn`.
 *
 * @param {String} event
 * @param {Function} fn
 * @return {Emitter}
 * @api public
 */

Emitter.prototype.on =
Emitter.prototype.addEventListener = function(event, fn){
  this._callbacks = this._callbacks || {};
  (this._callbacks[event] = this._callbacks[event] || [])
    .push(fn);
  return this;
};

/**
 * Adds an `event` listener that will be invoked a single
 * time then automatically removed.
 *
 * @param {String} event
 * @param {Function} fn
 * @return {Emitter}
 * @api public
 */

Emitter.prototype.once = function(event, fn){
  var self = this;
  this._callbacks = this._callbacks || {};

  function on() {
    self.off(event, on);
    fn.apply(this, arguments);
  }

  on.fn = fn;
  this.on(event, on);
  return this;
};

/**
 * Remove the given callback for `event` or all
 * registered callbacks.
 *
 * @param {String} event
 * @param {Function} fn
 * @return {Emitter}
 * @api public
 */

Emitter.prototype.off =
Emitter.prototype.removeListener =
Emitter.prototype.removeAllListeners =
Emitter.prototype.removeEventListener = function(event, fn){
  this._callbacks = this._callbacks || {};

  // all
  if (0 == arguments.length) {
    this._callbacks = {};
    return this;
  }

  // specific event
  var callbacks = this._callbacks[event];
  if (!callbacks) return this;

  // remove all handlers
  if (1 == arguments.length) {
    delete this._callbacks[event];
    return this;
  }

  // remove specific handler
  var cb;
  for (var i = 0; i < callbacks.length; i++) {
    cb = callbacks[i];
    if (cb === fn || cb.fn === fn) {
      callbacks.splice(i, 1);
      break;
    }
  }
  return this;
};

/**
 * Emit `event` with the given args.
 *
 * @param {String} event
 * @param {Mixed} ...
 * @return {Emitter}
 */

Emitter.prototype.emit = function(event){
  this._callbacks = this._callbacks || {};
  var args = [].slice.call(arguments, 1)
    , callbacks = this._callbacks[event];

  if (callbacks) {
    callbacks = callbacks.slice(0);
    for (var i = 0, len = callbacks.length; i < len; ++i) {
      callbacks[i].apply(this, args);
    }
  }

  return this;
};

/**
 * Return array of callbacks for `event`.
 *
 * @param {String} event
 * @return {Array}
 * @api public
 */

Emitter.prototype.listeners = function(event){
  this._callbacks = this._callbacks || {};
  return this._callbacks[event] || [];
};

/**
 * Check if this emitter has `event` handlers.
 *
 * @param {String} event
 * @return {Boolean}
 * @api public
 */

Emitter.prototype.hasListeners = function(event){
  return !! this.listeners(event).length;
};

});
require.register("post/index.js", function(exports, require, module){
var Emitter = require('emitter'),
		attach = window.addEventListener ? 'addEventListener' : 'attachEvent',
		detach = window.removeEventListener ? 'removeEventListener' : 'detachEvent',
		prefix = attach !== 'addEventListener' ? 'on' : '';

//TODO: we could encapsulte an id into the postMessage message
//Example
//  message = [...];
//  message._id = "...";
//  
// but it'd mean that it could only receive messages from an other post component.

/**
 * Expose 'PostEmitter'
 */

module.exports = PostEmitter;


/**
 * PostEmitter constructor.
 * Listen local and remote messages.
 * 
 * @api public
 */

function PostEmitter() {
	var _this = this;
	//might be global
	this._listener = function(ev) {
		//check origin
		//then
		var data = ev.data;
		_this.emit.apply(_this, data instanceof Array ? data : [data]);
	};
	window[attach](prefix + 'message', this._listener);
}


Emitter(PostEmitter.prototype);


/**
 * Emit local or cross-origin messages.
 * @param {String} topic
 * @param {Amy}  
 * @return {Function}
 * @api public
 */

PostEmitter.prototype.emit = function() {
	var args = arguments;
	Emitter.prototype.emit.apply(this, args);
	return function(domain) {
		window.postMessage([].slice.call(args), domain || window.location.href);
	};
};


/**
 * Remove post message listener.
 * @api public
 */

PostEmitter.prototype.dispose = function() {
	window[detach](prefix + 'message', this._listener);
	this.off();
};

});
require.alias("component-emitter/index.js", "post/deps/emitter/index.js");
require.alias("component-emitter/index.js", "emitter/index.js");

require.alias("post/index.js", "post/index.js");if (typeof exports == "object") {
  module.exports = require("post");
} else if (typeof define == "function" && define.amd) {
  define([], function(){ return require("post"); });
} else {
  this["post"] = require("post");
}})();