Fix ICS generator
continuous-integration/drone/pr Build encountered an error Details

Specifically, adds DTSTAMP properties to all of the objects (the calendar and
the events), terminates lines in CRLF, and splits the UID over 2 lines so the
validator is happy with me.
This commit is contained in:
Robert Miles 2020-07-02 22:30:22 -04:00
parent 9a928f4a39
commit f409367cfe
1 changed files with 28 additions and 15 deletions

View File

@ -11,8 +11,8 @@ $context = stream_context_create([
]
]);
$from = gmdate("Y-m-d\TH:i:s\Z", strtotime("now + 1 day"));
$to = gmdate("Y-m-d\TH:i:s\Z", strtotime("now + 8 days"));
$from = gmdate("Y-m-d\T00:00:00\Z", strtotime(date("w") ? "last sunday" : "sunday"));
$to = gmdate("Y-m-d\T00:00:00\Z", strtotime(date("w") ? "sunday" : "next sunday"));
$schedule = json_decode(
file_get_contents(
@ -31,35 +31,48 @@ function formatdate($date) {
return gmdate("Ymd\THis\Z", strtotime($date));
}
header("Content-Type: text/calendar");
// ICS generation. Here be dragons.
// I created the file using a Python script and reverse-engineered it to figure this out.
header("Content-Type: text/calendar");
// the iCalendar Validator throws a hissy fit if lines aren't CRLF terminated
define("ICS_EOL","\r\n");
// Header.
echo "BEGIN:VCALENDAR".PHP_EOL;
echo "VERSION:2.0".PHP_EOL;
echo "PRODID:tilderadio schedule".PHP_EOL;
echo "BEGIN:VCALENDAR".ICS_EOL;
echo "VERSION:2.0".ICS_EOL;
echo "PRODID:tilderadio schedule".ICS_EOL;
echo "DTSTAMP:".formatdate("now").ICS_EOL;
foreach ($schedule as $event) {
// The VEVENT structure's pretty easy to generate, especially since we're already in UTC.
echo "BEGIN:VEVENT".PHP_EOL;
// First, the event start and end.
echo "DTEND:".formatdate($event["end"]).PHP_EOL;
echo "DTSTART:".formatdate($event["start"]).PHP_EOL;
echo "BEGIN:VEVENT".ICS_EOL;
// First, we need a creation date.
// Just go with now.
echo "DTSTAMP:".formatdate("now").ICS_EOL;
// Next, the event start and end.
echo "DTEND:".formatdate($event["end"]).ICS_EOL;
echo "DTSTART:".formatdate($event["start"]).ICS_EOL;
// Next, the recurrence rule.
// We assume the format is weekly. (No DJs have requested any other frequency yet.)
echo "RRULE:FREQ=WEEKLY".ICS_EOL;
// Next, the event title, or "summary" as the spec calls it.
echo "SUMMARY:DJ ".$event["title"].PHP_EOL;
echo "SUMMARY:DJ ".$event["title"].ICS_EOL;
// Finally, a unique ID for this event.
// To make absolutely certain we don't repeat the same event ID, I decided to use a SHA256 hash of the event structure.
echo "UID:";
echo hash("sha256",json_encode($event));
echo "@tilderadio.org".PHP_EOL;
// to avoid the validator complaining about lines longer than 75 characters, split after the hash
echo ICS_EOL." ";
// Now finish the address UID
echo "@tilderadio.org".ICS_EOL;
// Finally, close the VEVENT structure.
echo "END:VEVENT".PHP_EOL;
echo "END:VEVENT".ICS_EOL;
// Next event?
}
// Finally, close out the VCALENDAR structure.
echo "END:VCALENDAR".PHP_EOL;
echo "END:VCALENDAR".ICS_EOL;
?>