How can I use PHP to dynamically publish an ical file to be read by Google Calendar?
This should be very simple if Google Calendar does not require the *.ics
-extension (which will require some URL rewriting in the server).
$ical = "BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//hacksw/handcal//NONSGML v1.0//EN
BEGIN:VEVENT
UID:" . md5(uniqid(mt_rand(), true)) . "@yourhost.test
DTSTAMP:" . gmdate('Ymd').'T'. gmdate('His') . "Z
DTSTART:19970714T170000Z
DTEND:19970715T035959Z
SUMMARY:Bastille Day Party
END:VEVENT
END:VCALENDAR";
//set correct content-type-header
header('Content-type: text/calendar; charset=utf-8');
header('Content-Disposition: inline; filename=calendar.ics');
echo $ical;
exit;
That's essentially all you need to make a client think that you're serving a iCalendar file, even though there might be some issues regarding caching, text encoding and so on. But you can start experimenting with this simple code.
A note of personal experience in addition to both Stefan Gehrig's answer and Dave None's answer (and mmmshuddup's reply):
I was having validation problems using both \n and PHP_EOL when I used the ICS validator at http://severinghaus.org/projects/icv/
I learned I had to use \r\n in order to get it to validate properly, so this was my solution:
function dateToCal($timestamp) {
return date('Ymd\Tgis\Z', $timestamp);
}
function escapeString($string) {
return preg_replace('/([\,;])/','\\\$1', $string);
}
$eol = "\r\n";
$load = "BEGIN:VCALENDAR" . $eol .
"VERSION:2.0" . $eol .
"PRODID:-//project/author//NONSGML v1.0//EN" . $eol .
"CALSCALE:GREGORIAN" . $eol .
"BEGIN:VEVENT" . $eol .
"DTEND:" . dateToCal($end) . $eol .
"UID:" . $id . $eol .
"DTSTAMP:" . dateToCal(time()) . $eol .
"DESCRIPTION:" . htmlspecialchars($title) . $eol .
"URL;VALUE=URI:" . htmlspecialchars($url) . $eol .
"SUMMARY:" . htmlspecialchars($description) . $eol .
"DTSTART:" . dateToCal($start) . $eol .
"END:VEVENT" . $eol .
"END:VCALENDAR";
$filename="Event-".$id;
// Set the headers
header('Content-type: text/calendar; charset=utf-8');
header('Content-Disposition: attachment; filename=' . $filename);
// Dump load
echo $load;
That stopped my parse errors and made my ICS files validate properly.
There is an excellent eluceo/ical package that allows you to easily create ics files.
Here is an example usage from docs:
// 1. Create new calendar
$vCalendar = new \Eluceo\iCal\Component\Calendar('www.example.com');
// 2. Create an event
$vEvent = new \Eluceo\iCal\Component\Event();
$vEvent->setDtStart(new \DateTime('2012-12-24'));
$vEvent->setDtEnd(new \DateTime('2012-12-24'));
$vEvent->setNoTime(true);
$vEvent->setSummary('Christmas');
// Adding Timezone (optional)
$vEvent->setUseTimezone(true);
// 3. Add event to calendar
$vCalendar->addComponent($vEvent);
// 4. Set headers
header('Content-Type: text/calendar; charset=utf-8');
header('Content-Disposition: attachment; filename="cal.ics"');
// 5. Output
echo $vCalendar->render();