Build SimplePie object based on RSS or Atom feed from URL.

Signature

fetch_feed( $url )
url
 (mixed) URL of feed to retrieve. If an array of URLs, the feeds are merged using SimplePie's multifeed feature. See also {@link ​http://simplepie.org/wiki/faq/typical_multifeed_gotchas

Return

(WP_Error|SimplePie) WP_Error object on failure or SimplePie object on success

Source

function fetch_feed( $url ) {
	if ( ! class_exists( 'SimplePie', false ) ) {
		require_once( ABSPATH . WPINC . '/class-simplepie.php' );
	}

	require_once( ABSPATH . WPINC . '/class-wp-feed-cache.php' );
	require_once( ABSPATH . WPINC . '/class-wp-feed-cache-transient.php' );
	require_once( ABSPATH . WPINC . '/class-wp-simplepie-file.php' );
	require_once( ABSPATH . WPINC . '/class-wp-simplepie-sanitize-kses.php' );

	$feed = new SimplePie();

	$feed->set_sanitize_class( 'WP_SimplePie_Sanitize_KSES' );
	// We must manually overwrite $feed->sanitize because SimplePie's
	// constructor sets it before we have a chance to set the sanitization class
	$feed->sanitize = new WP_SimplePie_Sanitize_KSES();

	$feed->set_cache_class( 'WP_Feed_Cache' );
	$feed->set_file_class( 'WP_SimplePie_File' );

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