feat: expose event log via debug

Author: gajus

README.md

@@ -6,6 +6,7 @@
 * [Usage](#usage)
     * [Events](#events)
 * [Examples](#examples)
+* [Debugging](#debugging)
 * [Download](#download)
 * [Running the Examples](#running-the-examples)
 
@@ -89,13 +90,16 @@ player
 player.on('stateChange', (event) => {
     // event.data
 });
- ```
- 
+
+```
+
 `player.off` removes a previously added event listener, e.g.
 
 ```js
 var listener = player.on(/* ... */);
-player.off(listener)
+
+player.off(listener);
+
 ```
 
 ## Examples
@@ -104,6 +108,19 @@ player.off(listener)
 * [Multiple players](./examples/src/multiple-players/index.html).
 * [Registering events handlers](./examples/src/registering-event-handlers/index.html).
 
+## Debugging
+
+`youtube-player` is using [`debug`](https://www.npmjs.com/package/debug) module to expose debugging information.
+
+The `debug` namespace is "youtube-player".
+
+To display `youtube-player` logs configure `localStorage.debug`, e.g.
+
+```js
+localStorage.debug = 'youtube-player:*';
+
+```
+
 ## Download
 
 Using [NPM](https://www.npmjs.org/):

package.json

@@ -12,6 +12,7 @@
   },
   "dependencies": {
     "babel-runtime": "^6.23.0",
+    "debug": "^2.6.6",
     "load-script": "^1.0.0",
     "lodash": "^4.17.4",
     "sister": "^3.0.0"

src/YouTubePlayer.js

@@ -1,6 +1,7 @@
 // @flow
 
 import _ from 'lodash';
+import createDebug from 'debug';
 import functionNames from './functionNames';
 import eventNames from './eventNames';
 import FunctionStateMap from './FunctionStateMap';
@@ -9,6 +10,8 @@ import type {
   YouTubePlayerType
 } from './types';
 
+const debug = createDebug('youtube-player');
+
 const YouTubePlayer = {};
 
 type EventHandlerMapType = {
@@ -29,6 +32,8 @@ YouTubePlayer.proxyEvents = (emitter: EmitterType): EventHandlerMapType => {
     const onEventName = 'on' + _.upperFirst(eventName);
 
     events[onEventName] = (event) => {
+      debug('event "%s"', onEventName, event);
+
       emitter.trigger(eventName, event);
     };
   }