Add public method subscribers() to get a readonly object of the curre…

…nt subscribers.

.eslintrc.json

@@ -6,7 +6,9 @@
     "commonjs": true,
     "amd": true
   },
-  "globals": {},
+  "globals": {
+    "PubSub": false
+  },
   "rules": {
     /* Possible Errors */
 

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ## v3.1.0
 - `hasSubscribers` checks if there is at least one subscriber, no matter its name, if no argument is passed.
+- Add public method `subscribers()` to get a readonly object of the current subscribers.
 
 ## v3.0.0
 

README.md

@@ -40,6 +40,7 @@ For API updates and breaking changes, check the [CHANGELOG](https://github.com/g
     * [.unsubscribe(topic)](#PubSub+unsubscribe) ⇒ <code>boolean</code> &#124; <code>string</code>
     * [.unsubscribeAll()](#PubSub+unsubscribeAll) ⇒ <code>[PubSub](#PubSub)</code>
     * [.hasSubscribers([topic])](#PubSub+hasSubscribers) ⇒ <code>Boolean</code>
+    * [.subscribers()](#PubSub+subscribers) ⇒ <code>object</code>
     * [.alias(aliasMap)](#PubSub+alias) ⇒ <code>[PubSub](#PubSub)</code>
 
 <a name="new_PubSub_new"></a>
@@ -199,6 +200,25 @@ pubsub.on('message', function (data) {
 pubsub.hasSubscribers('message');
 // -> true
 ```
+<a name="PubSub+subscribers"></a>
+
+### pubSub.subscribers() ⇒ <code>object</code>
+Gets all the subscribers as a key value pair of topic's name and event listener bound.
+
+**Kind**: instance method of <code>[PubSub](#PubSub)</code>  
+**Returns**: <code>object</code> - A readonly object with all subscribers.  
+**this**: <code>{PubSub}</code>  
+**Example**  
+```js
+var pubsub = new PubSub();
+
+pubsub.subscribe('message', listener);
+pubsub.subscribe('message', listener);
+pubsub.subscribe('another_message', listener);
+
+pubsub.subscribers();
+// -> Object { message: Array[2], another_message: Array[1] }
+```
 <a name="PubSub+alias"></a>
 
 ### pubSub.alias(aliasMap) ⇒ <code>[PubSub](#PubSub)</code>

src/pubsub.js

@@ -20,6 +20,26 @@
 }('PubSub', this, function () {
   'use strict';
 
+  function extend() {
+    var i, l, key;
+
+    for (i = 1, l = arguments.length; i < l; i++) {
+      for (key in arguments[i]) {
+        if (Object.prototype.hasOwnProperty.call(arguments[i], key)) {
+          if (arguments[i][key] && arguments[i][key].constructor &&
+              arguments[i][key].constructor === Object) {
+            arguments[0][key] = arguments[0][key] || {};
+            extend(arguments[0][key], arguments[i][key]);
+          } else {
+            arguments[0][key] = arguments[i][key];
+          }
+        }
+      }
+    }
+
+    return arguments[0];
+  }
+
   function forOwn(obj, callback, thisArg) {
     var key;
 
@@ -308,6 +328,27 @@
     return false;
   };
 
+  /**
+   * Gets all the subscribers as a key value pair of topic's name and event listener bound.
+   *
+   * @memberof PubSub
+   * @this {PubSub}
+   * @return {object} A readonly object with all subscribers.
+   * @example
+   *
+   * var pubsub = new PubSub();
+   *
+   * pubsub.subscribe('message', listener);
+   * pubsub.subscribe('message', listener);
+   * pubsub.subscribe('another_message', listener);
+   *
+   * pubsub.subscribers();
+   * // -> Object { message: Array[2], another_message: Array[1] }
+   */
+  PubSub.prototype.subscribers = function () {
+    return extend({}, this._pubsub_topics);
+  };
+
   /**
    * Creates aliases for public methods.
    *

tests/pubsub.specs.js

@@ -1,25 +1,26 @@
+/* eslint-disable strict, no-unused-vars, no-use-before-define */
+
 describe('new PubSub', function () {
   it('Creates a new instance of PubSub.', function () {
     expect(new PubSub()).not.toBeNull();
   });
 });
 
-
 // Subscribe scenarios.
 describe('Subscribe to an event.', function () {
   it('Subscribes to an event called: "example-event".', function () {
+    var ps = new PubSub();
+
     function listener() {}
 
-    var ps = new PubSub();
     expect(ps.subscribe('example-event', listener)).toBe(0);
   });
 });
 
-
 // Publish scenarios.
 describe('Publish/Emmit an event.', function () {
-  function listener() {}
   var ps = new PubSub();
+  function listener() {}
   ps.subscribe('example-event', listener);
 
   it('Publishes "example-event" passing data: "{ dummyKey : \'dummyValue\' }".', function () {
@@ -29,7 +30,7 @@ describe('Publish/Emmit an event.', function () {
       dummyKey: 'dummyValue'
     });
 
-    expect(ps.publish).toHaveBeenCalledWith('example-event', { dummyKey: 'dummyValue' });
+    expect(ps.publish).toHaveBeenCalledWith('example-event', {dummyKey: 'dummyValue'});
   });
 
   it('Publishes "example-event".', function () {
@@ -45,30 +46,31 @@ describe('Publish/Emmit an event.', function () {
   });
 });
 
-
 // Unsubscribe scenarios.
 describe('Unsubscribe from event.', function () {
   it('Unsubscribes from event using the event name ("example-event").', function () {
+    var ps = new PubSub();
+    var unsub;
+
     function listener() {}
 
-    var ps = new PubSub();
     ps.subscribe('example-event', listener);
-    var unsub = ps.unsubscribe('example-event');
+    unsub = ps.unsubscribe('example-event');
 
     expect(unsub).toBe('example-event');
-    expect(ps._pubsub_topics['example-event'].length).toBe(0);
+    expect(ps.hasSubscribers('example-event')).toBe(false);
   });
 
   it('Unsubscribes from event using tokenized reference to the subscription.', function () {
-    function listener() {}
-
     var ps = new PubSub(),
       sub = ps.subscribe('example-event', listener),
       sub2 = ps.subscribe('example-event', listener),
       sub3 = ps.subscribe('example-event', listener);
 
+    function listener() {}
+
     expect(ps.unsubscribe(sub)).toBe(0);
-    expect(ps._pubsub_topics['example-event'].length).toBe(2);
+    expect(ps.subscribers()['example-event'].length).toBe(2);
   });
 
   it('Unsubscribes from an event that was not subscribed before.', function () {
@@ -79,7 +81,6 @@ describe('Unsubscribe from event.', function () {
   });
 });
 
-
 // Check if there are subscribers for a specific topic.
 describe('Check if there are subscribers for a specific topic.', function () {
   it('Should return true when checking if there are subscribers for "message" event.', function () {
@@ -109,7 +110,7 @@ describe('Check if there are subscribers for a specific topic.', function () {
 describe('Clears all subscriptions at once', function () {
   it('Should unsubscribe from all subscriptions', function () {
     var ps = new PubSub();
-    var listener = function listener() {}
+    var listener = function listener() {};
 
     // Subscribe to some events
     ps.subscribe('eventA', listener);