Essence

Essence is a simple PHP library to extract media informations from websites, like youtube videos, twitter statuses or blog articles.

If you were already using Essence 1.x.x, you should take a look at the migration guide.

• Example
• What you get
• Advanced usage
• Configuration
• Customization
• Third-party libraries

Example

Essence is designed to be really easy to use. Using the main class of the library, you can retrieve informations in just those few lines:

require_once 'path/to/essence/bootstrap.php';

$Essence = Essence\Essence::instance( );

$Media = $Essence->embed( 'http://www.youtube.com/watch?v=39e3KYAmXK4' );

if ( $Media ) {
	// That's all, you're good to go !
}

Then, just do anything you want with the data:

<article>
	<header>
		<h1><?php echo $Media->title; ?></h1>
		<p>By <?php echo $Media->authorName; ?></p>
	</header>

	<div class="player">
		<?php echo $Media->html; ?>
	</div>
</article>

What you get

Using Essence, you will mainly interact with Media objects. Media is a simple container for all the informations that are fetched from an URL.

Here are the default properties it provides:

• type
• version
• url
• title
• description
• authorName
• authorUrl
• providerName
• providerUrl
• cacheAge
• thumbnailUrl
• thumbnailWidth
• thumbnailHeight
• html
• width
• height

These properties were gathered from the OEmbed and OpenGraph specifications, and merged together in a united interface. Based on such standards, these properties should be a solid starting point.

However, "non-standard" properties can and will also be setted.

Here is how you can manipulate the Media properties:

// through dedicated methods
if ( !$Media->has( 'foo' )) {
	$Media->set( 'foo', 'bar' );
}

$value = $Media->get( 'foo' );

// or directly like a class attribute
$Media->customValue = 12;

Note that Essence will always try to fill the html property when it is not available.

Advanced usage

The Essence class provides some useful utility function to ensure you will get some informations.

Extracting URLs

The extract( ) method lets you extract embeddable URLs from a web page.

For example, here is how you could get the URL of all videos in a blog post:

$urls = $Essence->extract( 'http://www.blog.com/article' );

//	array(
//		'http://www.youtube.com/watch?v=123456'
//		'http://www.dailymotion.com/video/a1b2c_lolcat-fun'
//	)

You can then get informations from all the extracted URLs:

$medias = $Essence->embedAll( $urls );

//	array(
//		'http://www.youtube.com/watch?v=123456' => Media( ... )
//		'http://www.dailymotion.com/video/a1b2c_lolcat-fun' => Media( ... )
//	)

Replacing URLs in text

Essence can replace any embeddable URL in a text by informations about it. By default, any URL will be replaced by the html property of the found Media.

$text = 'Check out this awesome video: http://www.youtube.com/watch?v=123456'

echo $Essence->replace( $text );

//	Check out this awesome video: <iframe src="http://www.youtube.com/embed/123456"></iframe>

But you can do more by passing a callback to control which informations will replace the URL:

echo $Essence->replace( $text, function( $Media ) {
	return sprintf(
		'<p class="title">%s</p><div class="player">%s</div>',
		$Media->title,
		$Media->html
	);
});

//	Check out this awesome video:
//	<p class="title">Video title</p>
//	<div class="player">
//		<iframe src="http://www.youtube.com/embed/123456"></iframe>
//	<div>

This makes it easy to build rich templates or even to integrate a templating engine:

echo $Essence->replace( $text, function( $Media ) use ( $TwigTemplate ) {
	return $TwigTemplate->render( $Media->properties( ));
});

Configuring providers

It is possible to pass some options to the providers.

For example, OEmbed providers accepts the maxwidth and maxheight parameters, as specified in the OEmbed spec.

$Media = $Essence->embed(
	$url,
	array(
		'maxwidth' => 800,
		'maxheight' => 600
	)
);

$medias = $Essence->embedAll(
	$urls,
	array(
		'maxwidth' => 800,
		'maxheight' => 600
	)
);

$Media = $Essence->extract(
	$text,
	null,
	array(
		'maxwidth' => 800,
		'maxheight' => 600
	)
);

Other providers will just ignore the options they don't handle.

Configuration

Essence currently supports 36 specialized providers:

23hq, Bandcamp, Blip.tv, Cacoo, CanalPlus, Chirb.it, Clikthrough, CollegeHumour,
Dailymotion, Deviantart, Dipity, Flickr, Funnyordie, Howcast, Huffduffer, Hulu,
Ifixit, Imgur, Instagram, Mobypicture, Official.fm, Polldaddy, Qik, Revision3,
Scribd, Shoudio, Sketchfab, Slideshare, SoundCloud, Ted, Twitter, Vhx, Viddler,
Vimeo, Yfrog and Youtube.

You can configure these providers by passing a configuration array:

$Essence = Essence\Essence::instance( array(
	'providers' => array(

		// the OpenGraph provider will try to embed any URL that matches
		// the filter
		'Ted' => array(
			'class' => 'OpenGraph',
			'filter' => '#ted\.com/talks/.*#i'
		),

		// the OEmbed provider will query the endpoint, %s beeing replaced
		// by the requested URL.
		'Youtube' => array(
			'class' => 'OEmbed',
			'filter' => '#youtube\.com/.*#',
			'endpoint' => 'http://www.youtube.com/oembed?format=json&url=%s'
		)
	)
));

// you can also load a configuration array from a file
$Essence = Essence\Essence::instance( array(
	'providers' => 'path/to/config/file.php'
));

You can use custom providers by specifying a fully-qualified class name in the 'class' option.

If no configuration is provided, the default configuration will be loaded from the lib/providers.php file.

Customization

Almost everything in Essence can be configured through dependency injection. Under the hoods, the instance( ) method uses a dependency injection container to return a fully configured instance of Essence.

To customize the Essence behavior, the easiest way is to configure injection settings when building Essence:

$Essence = Essence\Essence::instance( array(

	// the container will return a new CustomCacheEngine each time a cache
	// engine is needed
	'Cache' => function( ) {
		return new CustomCacheEngine( );
	},

	// the container will return a unique instance of CustomHttpClient
	// each time an HTTP client is needed
	'Http' => Essence\Di\Container::unique( function( ) {
		return new CustomHttpClient( );
	})
));

The default injection settings are defined in the Standard container class.

Third-party libraries

• Interfaces to integrate other libraries: https://github.com/felixgirault/essence-interfaces
• CakePHP plugin: https://github.com/felixgirault/cakephp-essence
• Demo framework by Sean Steindl: https://github.com/laughingwithu/Essence_demo
• Symfony bundle by Ka Yue Yeung: https://github.com/kayue/KayueEssenceBundle

If you're interested in embedding videos, you should take a look at the Multiplayer lib. It allows you to build customizable embed codes painlessly:

$Multiplayer = new Multiplayer\Multiplayer( );

if ( $Media->type === 'video' ) {
	echo $Multiplayer->html(
		$Media->url,
		array(
			'autoPlay' => true,
			'highlightColor' => 'BADA55'
		)
	);
}