Retrieving and parsing RSS feed with SimplePie in WordPress

gistfile1.php

<?php
class Sample_WP_Feed_Parser {
	var $source = 'http://www.example.com/feed/'; 
	var $feed = null; 
	var $items = array(); 

	/**
	 * Retrieve the appropriate items from the requested feed
	 */
	function fetch_feed() {
		if ( ! $this->test_feed() )
			return new WP_Error( 'feed-not-found', __( 'The requested feed could not be retrieved' ) );
		
		if ( ! class_exists( 'SimplePie' ) )
			require_once( ABSPATH . WPINC . '/class-feed.php' );
		
		$this->feed = new SimplePie();
		$this->feed->set_feed_url( $this->source );
		$this->feed->set_cache_class( 'WP_Feed_Cache' );
		$this->feed->set_file_class( 'WP_SimplePie_File' );
		$this->feed->set_cache_duration( apply_filters( 'wp_feed_cache_transient_lifetime', 43200, $this->source ) );
		do_action_ref_array( 'wp_feed_options', array( &$this->feed, $this->source ) );
		$this->feed->init();
		$this->feed->handle_content_type();
	
		if ( $this->feed->error() ) {
			return $this->feed = new WP_Error( 'simplepie-error', $this->feed->error() );
		}
		
		return $this->feed;
	}
	
	/**
	 * Process the requested feed items and turn them into slides
	 */
	function process_feed() {
		$this->fetch_feed();
		if ( is_wp_error( $this->feed ) )
			return;
		
		foreach( $this->feed->get_items( 0, 10 ) as $item ) {
			$tmpimg = $item->get_enclosure();
			if ( empty( $tmpimg ) || ! is_object( $tmpimg ) )
				continue;
			
			$img = array( 'src' => $tmpimg->get_link(), 'alt' => null );
			$caption = array( 'title' => $item->get_title(), 'text' => $item->get_description() );
			$link = array( 'url' => $item->get_permalink() );
			
			$this->slides[] = new UMW_Home_Slide( $img, $caption, $link );
		}
	}
	
}