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 ) {
	require_once( ABSPATH . WPINC . '/class-feed.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' );

	$feed->set_feed_url( $url );
	/** This filter is documented in wp-includes/class-feed.php */
	$feed->set_cache_duration( apply_filters( 'wp_feed_cache_transient_lifetime', 12 * HOUR_IN_SECONDS, $url ) );
	/**
	 * Fires just before processing the SimplePie feed object.
	 *
	 * @since 3.0.0
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