This is entirely based on Event Organiser (a plug-in I’ve developed). The code is lifted almost straight from the source but with alterations. As such I’ve not tested the code as given.
Step 1: Create a feed
This is simple:
add_action('init','wpse63611_add_events_feed');
function wpse63611_add_events_feed(){
add_feed('my-events','wpse63611_events_feed_output');
}
This adds a feed to your site: www.site.com?feed=my-events
or www.site.com/feed/my-events
if you have pretty permalinks. The wpse63611_events_feed_output()
callback will output the contents of the ICAL file. But first…
Step 2: Alter the query
WordPress doesn’t know what this feed is meant to contain. Here we use the pre_get_posts
to tell WordPress, that for this feed we want posts of post type ‘wr_event’. We could get events from a particular category, venue or between certain dates too.
By separating out the query from the output, you can have multiple feeds which use the same output function – but query different events (based on time, location, category etc).
add_action( 'pre_get_posts', 'wpse63611_event_feed_query' );
function wpse63611_event_feed_query( $query ) {
$yesterday = current_time('timestamp') - 24*60*60;
$compare = $latest ? '>' : '<';
if( $query->is_feed('eo-events') ){
$query->set('post_type', 'wr_event');
$query->set('posts_per_page', -1);
$query->set('meta_key', 'event_date');
$query->set('orderby', 'meta_value_num');
$query->set('order', 'ASC');
$query->set('meta_compare', $compare);
$query->set('meta_value', $value);
}
}
Step 3: The contents of the ICS file
As mentioned earlier, wpse63611_events_feed_output()
is responsible for printing the output of our feed.
function wpse63611_events_feed_output(){
//Let's give it a name;
$filename = urlencode( 'my_events' . date('Y-m-d') . '.ics' );
//Collect output
ob_start();
// File header
header( 'Content-Description: File Transfer' );
header( 'Content-Disposition: attachment; filename=" . $filename );
header("Content-type: text/calendar');
header("Pragma: 0");
header("Expires: 0");
?>
BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//<?php get_bloginfo('name'); ?>//NONSGML Events //EN
CALSCALE:GREGORIAN
X-WR-CALNAME:<?php echo get_bloginfo('name');?> - Events
<?php
// Loop through events
if ( have_posts() ):
$now = new DateTime();
$datestamp =$now->format('Ymd\THis\Z');
while( have_posts() ): the_post();
global $post;
$uid = md5(uniqid(mt_rand(), true))."@mysite.com";
$start = unixToiCal(get_event_date($post), get_event_time($post));
$end = unixToiCal(get_event_end_date($post), get_event_end_time($post));
$summary = wpse63611_escape_icalText(get_the_title())
$description = apply_filters('the_excerpt_rss', get_the_content());
$description = wpse63611_escape_icalText($description);
BEGIN:VEVENT
UID:<?php echo $uid;?>
DTSTAMP:<?php echo $datestamp;?>
DTSTART:<?php echo $start; ?>
DTEND:<?php echo $end; ?>
SUMMARY:<?php echo wpse63611_esc_ical_text($summary);?>
DESCRIPTION:<?php echo wpse63611_esc_ical_text($description);?>
END:VEVENT
endwhile;
endif;
?>
END:VCALENDAR
<?php
//Collect output and echo
$eventsical = ob_get_contents();
ob_end_clean();
echo $eventsical;
exit();
}
I’ve used the unixToiCal
function you’ve defined in your question. I’ve also used the following to remove anything that might upset an ICAL parser:
function wpse63611_esc_ical_text( $text="" ){
$text = str_replace("\\", "\\\\", $text);
$text = str_replace(",", "\,", $text);
$text = str_replace(";", "\;", $text);
$text = str_replace("\n", "\n ", $text);
return $text;
}