rss-event.php

<?php
/**
 * Template Name: Event RSS
 *
 * This template is used to display
 * RSS feed for Event posts.
 *
 * @package MITLibraries-News
 * @since 1.0
 * @link https://yoast.com/custom-rss-feeds-wordpress/ Source
 */

$numposts = 5;

/**
 * This outputs a formatted timestamp.
 *
 * @param string $timestamp A provided timestamp.
 * @link https://yoast.com/custom-rss-feeds-wordpress/ Source
 */
function yoast_rss_date( $timestamp = null ) {
	$timestamp = ( null == $timestamp ) ? time() : $timestamp;
	echo date( DATE_RSS, $timestamp );
}

/**
 * This outputs an excerpt of a source string with ellipsis on a word boundary.
 *
 * @param string $string The string to be trimmed.
 * @param int    $length The desired length of excerpt.
 * @param string $replacer The ellipsis or continuation string to indicate truncation.
 * @link https://yoast.com/custom-rss-feeds-wordpress/ Source
 */
function yoast_rss_text_limit( $string, $length, $replacer = '...' ) {
	$string = strip_tags( $string );
	if ( strlen( $string ) > $length ) {
	return (preg_match( '/^(.*)\W.*$/', substr( $string, 0, $length + 1 ), $matches ) ? $matches[1] : substr( $string, 0, $length )) . $replacer; }
	return $string;
}



$args = array(
	'post__not_in' => get_option( 'sticky_posts' ),
	'meta_key' => 'is_event',
	'orderby' => 'meta_value_num',
	'order' => 'DESC',
	'posts_per_page' => -1,


);
$the_query = new WP_Query( $args );
$lastpost = $numposts - 1;
header( 'Content-Type: application/rss+xml; charset=UTF-8' );
echo '<?xml version="1.0"?>';
?>

<rss version="2.0">
<channel>
	<title>MIT Libraries Events</title>
	<link>//libraries.mit.edu/news/events/</link>
	<description>The latest events from the MIT Libraries</description>
	<language>en-us</language>
	<pubDate><?php yoast_rss_date( strtotime( $ps[ $lastpost ]->post_date_gmt ) ); ?></pubDate>
	<lastBuildDate><?php yoast_rss_date( strtotime( $ps[ $lastpost ]->post_date_gmt ) ); ?></lastBuildDate>
	<managingEditor>hartman@mit.edu (Stephanie Hartman)</managingEditor>
<?php while ( $the_query->have_posts() ) : $the_query->the_post(); ?>

	<item>
	<title><?php echo get_the_title( $post->ID ); ?></title>
	<link><?php the_permalink_rss( $post->ID ); ?></link>
	<description><?php echo '<![CDATA[' . yoast_rss_text_limit( $post->post_content, 500 ) . '<br/><br/>Keep on reading: <a href="' . get_permalink( $post->ID ) . '">' . get_the_title( $post->ID ) . '</a>' . ']]>';  ?></description>
	<pubDate><?php yoast_rss_date( strtotime( $post->post_date_gmt ) ); ?></pubDate>
	<guid><?php echo get_permalink( $post->ID ); ?></guid>
	</item>
<?php endwhile; ?>
</channel>
</rss>