Wordpress: Open Graph Tags

og.php

/*
	Open Graph Tags

	@author Kevin Jantzer
	@since 2014-12-13

	orginal code: https://wordpress.org/plugins/facebook-featured-image-and-open-graph-meta-tags/

	Info
	- http://ogp.me/
	- https://developers.facebook.com/tools/debug/og/object/
*/

// Allow for Facebooks's markup language
add_filter('language_attributes', 'add_og_xml_ns');
function add_og_xml_ns($content) {
	return ' xmlns:og="http://ogp.me/ns#" ' . $content;
}

add_filter('language_attributes', 'add_fb_xml_ns');
function add_fb_xml_ns($content) {
	return ' xmlns:fb="https://www.facebook.com/2008/fbml" ' . $content;
}

// Set your Open Graph Meta Tags
function fb_ogmeta_header() {

	global $post;

	$tags = array(
		'title' => get_the_title(),
		'description' => strip_tags(do_shortcode($post->post_content)),
		'url' => get_the_permalink(),
		'imgs' => get_post_img_urls(),
		'video' => null,
		'type' => (is_single() || is_page()) ? "article" : "website",
		'site' => get_bloginfo('name')
	);

	global $youtube_thumbnail;
	global $youtube_url;
	global $youtube_url_secure;

	if( $youtube_thumbnail )
		array_unshift($tags['imgs'], $youtube_thumbnail);

	if( $youtube_url ){
		$tags['video'] = array(
			'url' => $youtube_url,
			'url_secure' => $youtube_url_secure,
			'width' => '640',
			'height' => '360'
		);
	}

	?>
	<!-- Open Graph Meta Tags for Facebook and LinkedIn Sharing !-->
	<meta property="og:title" content="<?php echo $tags['title']; ?>"/>
	<meta property="og:description" content="<?php echo $tags['description']; ?>" />
	<meta property="og:url" content="<?php echo $tags['url']; ?>"/>

	<?php foreach($tags['imgs'] as $img ): ?>
	<meta property="og:image" content="<?php echo $img; ?>" />
	<?php endforeach; ?>

	<?php if( $tags['video'] ): ?>
	<meta property="og:video" content="<?php echo $tags['video']['url']; ?>">
	<meta property="og:video:secure_url" content="<?php echo $tags['video']['url_secure']; ?>">
	<meta property="og:video:width" content="<?php echo $tags['video']['width']; ?>" />
	<meta property="og:video:height" content="<?php echo $tags['video']['height']; ?>" />
	<?php endif; ?>

	<meta property="og:type" content="<?php echo $tags['type']; ?>" />
	<meta property="og:site_name" content="<?php echo $tags['site']; ?>"/>

	<?php
}
add_action('wp_head', 'fb_ogmeta_header');


/*
	Post Images - returns array of img urls used in post
*/
function get_post_img_urls($post_id=null) {

	global $post;
	$post_id = $post_id ? $post_id : $post->ID;
	$imgs = array();

	$feature_img = wp_get_attachment_image_src(get_post_thumbnail_id ($post_id), 'full');

	if( $feature_img )
		$imgs[] = $feature_img[0];

	$attachments = get_children(array(
		'post_parent' => $post_id,
		'post_type' => 'attachment',
		'post_mime_type' => 'image'
	));

	if (is_array($attachments)) foreach ($attachments as $a)
		$imgs[] = $a->guid;

	return $imgs;
}