Code for Adding Twitter Cards

twitter-card-genesis.php

//Code for Adding Twitter Cards
 add_action('wp_head', 'add_twitter_cards');
 function add_twitter_cards() {
 if(is_single()) {
 $tc_url = get_permalink();
 $tc_title = get_the_title();
 $tc_description = get_the_excerpt();
 $tc_image = wp_get_attachment_image_src( get_post_thumbnail_id($post->ID), full );
 $tc_image_thumb = $tc_image[0];
 $tc_author = str_replace('@', '', get_the_author_meta('twitter'));
 ?>
 <meta name="twitter:card" value="summary_large_image" />
 <meta name="twitter:site" value="@league_wp" />
 <meta name="twitter:title" value="<?php echo $tc_title; ?>" />
 <meta name="twitter:description" value="<?php echo $tc_description; ?>" />
 <meta name="twitter:url" value="<?php echo $tc_url; ?>" />
 <?php if($tc_image) { ?>
 <meta name="twitter:image" value="<?php echo $tc_image_thumb; ?>" />
 <?php } if($tc_author) { ?>
 <meta name="twitter:creator" value="@<?php echo $tc_author; ?>" />
 <?
 }
 }
 }