Support for DST in RRULES

[SSzretter]

I am downloading ics data from Google calendar and non-recurring events appear ok with the correct time, but recurring events are off by 1 hour. I am setting the timezone in my php and turning on $useTimeZoneWithRRules at least puts my times within 1 hour (with this set to false it was 6 hours off). Changing the time zones between EST and EST5EDT and America/New York makes no difference to the output (I tried passing false to the iCalDateToUnixTimestamp).

So I am thinking either something is broken with the parsing of this Google calendar RRULES, or it needs a way to account for DST, or possibly I have to change a setting?

date_default_timezone_set('EST5EDT');  // I have tried America/New York also
ini_set("date.timezone", "EST5EDT");
if (date('I', time()))
    echo 'We’re in DST!';  // **** WE ARE IN DST
else
    echo 'We’re not in DST!';

$ical = new ICal();
$ical->useTimeZoneWithRRules=true;
$ical->initURL('google calendar ics url');
$events = $ical->sortEventsWithOrder($ical->eventsFromInterval('3 days'));`
foreach ($events as $event)
{
    $start = date("Y-m-d h:i:s",$ical->iCalDateToUnixTimestamp($event->dtstart, true));  
    $end = date("Y-m-d h:i:s",$ical->iCalDateToUnixTimestamp($event->dtend, true)); 
    echo $start;
    echo $end;
}

BEGIN:VCALENDAR
PRODID:-//Google Inc//Google Calendar 70.9054//EN
VERSION:2.0
CALSCALE:GREGORIAN
METHOD:PUBLISH
X-WR-CALNAME:XXXTEST
X-WR-TIMEZONE:America/New_York
X-WR-CALDESC:
BEGIN:VTIMEZONE
TZID:America/New_York
X-LIC-LOCATION:America/New_York
BEGIN:DAYLIGHT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
DTSTART:19700308T020000
RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=2SU
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
DTSTART:19701101T020000
RRULE:FREQ=YEARLY;BYMONTH=11;BYDAY=1SU
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20170313T080000
DTEND;TZID=America/New_York:20170313T110000
RRULE:FREQ=WEEKLY;BYDAY=MO,WE,FR
DTSTAMP:20170319T130024Z
UID:XXXptseqtmp07al34@google.com
CREATED:20170318T203731Z
DESCRIPTION:
LAST-MODIFIED:20170318T223849Z
LOCATION:
SEQUENCE:2
STATUS:CONFIRMED
SUMMARY:Scott recur mwf
TRANSP:OPAQUE
END:VEVENT
BEGIN:VEVENT
DTSTART:20170318T120000Z
DTEND:20170318T130000Z
DTSTAMP:20170319T130024Z
UID:XXXkctlj90qg8@google.com
CREATED:20170318T211306Z
DESCRIPTION:
LAST-MODIFIED:20170318T220751Z
LOCATION:
SEQUENCE:1
STATUS:CONFIRMED
SUMMARY:test2
TRANSP:OPAQUE
END:VEVENT
END:VCALENDAR

[u01jmg3]

I believe this may be related to #105 - I have a fix coming so if you could try that once I release v2.0.3. It all relates to timezone settings.

[u01jmg3]

Fixed by the release of v2.0.3

[SSzretter]

I am not sure exactly what is wrong, but now after updating the library I am getting back these date/times:

2017-03-20 00:00:00  // $start = date("Y-m-d H:i:s",$ical->iCalDateToUnixTimestamp($event->dtstart, true))
2017-03-20 03:00:00 // $end = date("Y-m-d H:i:s",$ical->iCalDateToUnixTimestamp($event->dtend, true))

$ical->dtstart is 20170320T040000
$ical->dtend is 20170320T070000

The original google event is 8a-11a (America/New_York) FYI.

[u01jmg3]

• Refrain from using date() and instead use a DateTime object as per the update to the example in v2.0.3.
• I have loaded your iCal into the parser - here is the result
  • This looks correct to me

[SSzretter]

Ok - getting closer. So now if I set $ical->useTimeZoneWithRRules=false; and use your sample code using date object my recurring events are coming back with the correct times (8a-11a EST). I had to set that to false or it was still not returning the correct times.

However now my non-recurring event is now coming back with the incorrect time. The non-recurring event was in the sample ics I posted earlier and now it comes back with 12:00:00 - 13:00:00 instead of 08:00:00 - 09:00:00. So it is as if something is not working for the timezone for non-recurring in this scenario.

This is the code I use now based on what you sent me:

$dtstart = new DateTime('@' . (int) $ical->iCalDateToUnixTimestamp($event->dtstart));
$start   = $dtstart->format('Y-m-d H:i:s');
$dtend   = new DateTime('@' . (int) $ical->iCalDateToUnixTimestamp($event->dtend));
$end     = $dtend->format('Y-m-d H:i:s');

[u01jmg3]

• Use the constructor to override settings such as $useTimeZoneWithRRules
  • See example updated for v2.0.3
• For your non-recurring event, do not finalise DTSTART / DTEND with Z as the calendar timezone will not be applied
  • The reason for this is that it signifies Zulu time which means UTC
  • Use dev-master to pull in the fix I created for making use of the calendar timezone when Z is not present: a512c63
    • (This will get your non-recurring event working as you expect it to)
• If you want to use start and end times with timezones applied, I suggest using dtstart_tz / dtend_tz as per the snippet below
  • Worth noting that having $useTimeZoneWithRRules set to true will only apply the timezone to recurrence events and won't apply it to the parent recurrence event or any non-recurring events for the keys dstart and dtend
    • (This is why I suggested using dtstart_tz / dtend_tz to better fit your requirements)

---

$dtstart_tz = new DateTime('@' . (int) $ical->iCalDateToUnixTimestamp($event->dtstart_tz));
$start      = $dtstart_tz->format('Y-m-d H:i:s');
$dtend_tz   = new DateTime('@' . (int) $ical->iCalDateToUnixTimestamp($event->dtend_tz));
$end        = $dtend_tz->format('Y-m-d H:i:s');

[SSzretter]

No difference this morning when I tried the updated code, changed to the new constructor and used the dtstart_tz / dtend_tz. In fact, when I use those _tz fields it seems to pull the same time (not adjusting for timezone) regardless of any other setting. So even if I change the $useTimeZoneWithRRules the recurring events show as 4a-7a instead of 8a-11a. If I use the $event->dtstart (non-tz version), the recurring events look good with $useTimeZoneWithRRules set to false. However in all cases I currently do not seem to be able to get the non-recurring event to show the correct time no matter which settings or field I use. It shows 12:00:00 and 13:00:00 (but should be 8a-9a).

One question I do have - you mentioned for the non-recurring event 'do not finalise DTSTART / DTEND with Z'... What do you mean by that? Google is adding the Z (I included the link to the ics coming from google if you want to look at that)...

Here is a more complete sample of my current code. There is one non-recurring event from 8a-9a and a M/W/F recurring from 8a-11a my time zone (EST).

date_default_timezone_set('America/New_York');
ini_set("date.timezone", 'America/New_York');

$folder_id="https://calendar.google.com/calendar/ical/l0isqaou87j5hrha1eu2oac9jo%40group.calendar.google.com/public/basic.ics";

$ical = new ICal($folder_id, array(
    'defaultSpan'           => 2,
    'defaultWeekStart'      => 'MO',
    'useTimeZoneWithRRules' => false,
));


$events = $ical->sortEventsWithOrder($ical->eventsFromInterval('3 days'));
$out='';
if ($events) {
    foreach ($events as $event) {
        $subject = $event->summary;
        $id = $event->uid;
        
        $dtstart = new DateTime('@' . (int) $ical->iCalDateToUnixTimestamp($event->dtstart));  // _tz here does not work
        $start = $dtstart->format('Y-m-d H:i:s');
        $dtend = new DateTime('@' . (int) $ical->iCalDateToUnixTimestamp($event->dtend));   // _tz here does not work
        $end = $dtend->format('Y-m-d H:i:s');
        $location = $event->location;
        $out.= "<response>";
        $out.= "<subject>$subject</subject>";
        $out.= "<location>$location</location>";
        $out.= "<dtstart>$start</dtstart>";
        $out.= "<dtend>$end</dtend>";
        $out.= "<id>$id</id>";
        $out.= "<priority>0</priority>";
        $out.= "</response>";
    } //for each
}
echo $out;

It currently produces this - you can see the recurring event is correct with the code above, but the non-recurring event has the incorrect time (not adjusted for time zone). I tried using the dtstart_tz / dtend_tz fields and that did not help and in fact did not work for the recurring event.

<response>
    <subject>test2</subject>
    <location></location>
    <dtstart>2017-03-21 12:00:00</dtstart>
    <dtend>2017-03-21 13:00:00</dtend>
    <id>uqnt090jvr0en3cqkctlj90qg8@google.com</id>
    <priority>0</priority>
</response>
<response>
    <subject>Scott recur mwf</subject>
    <location></location>
    <dtstart>2017-03-22 08:00:00</dtstart>
    <dtend>2017-03-22 11:00:00</dtend>
    <id>9huhq46274rrptseqtmp07al34@google.com</id>
    <priority>0</priority>
</response>

[u01jmg3]

• Each time I answer your question I am having to edit your markdown before I can read what you have put.
  • Please preview your response before commenting so it is readable.
• Enclose code in 3 backticks to create a code block.

  ```
  Your code here
  ```

---

Google is adding the Z

• Okay, I have created a method for forcing the timezone when populating dtstart_tz / dtend_tz - see 9b2d1bc

  • Please therefore use the latest dev-master

• I have amended your code:

  date_default_timezone_set('America/New_York');
  ini_set('date.timezone', 'America/New_York');
  
  $filename = 'https://calendar.google.com/calendar/ical/l0isqaou87j5hrha1eu2oac9jo%40group.calendar.google.com/public/basic.ics';
  
  $ical = new ICal($filename, array(
      'defaultSpan'           => 2,
      'defaultWeekStart'      => 'MO',
      'useTimeZoneWithRRules' => false,
  ));
  
  $events = $ical->eventsFromInterval('3 days');
  $out = '';
  if ($events) {
      foreach ($events as $event) {
          $subject  = $event->summary;
          $id       = $event->uid;
          $dtstart  = new DateTime('@' . (int) $ical->iCalDateToUnixTimestamp($event->dtstart_tz));
          $start    = $dtstart->format('Y-m-d H:i:s');
          $dtend    = new DateTime('@' . (int) $ical->iCalDateToUnixTimestamp($event->dtend_tz));
          $end      = $dtend->format('Y-m-d H:i:s');
          $location = $event->location;
          $out     .= "<response>\n";
          $out     .= "\t<subject>$subject</subject>\n";
          $out     .= "\t<location>$location</location>\n";
          $out     .= "\t<dtstart>$start</dtstart>\n";
          $out     .= "\t<dtend>$end</dtend>\n";
          $out     .= "\t<id>$id</id>\n";
          $out     .= "\t<priority>0</priority>\n";
          $out     .= "</response>\n";
      }
  }
  
  $out = htmlspecialchars($out);
  echo "<pre>{$out}</pre>";

• Which correctly produces:

  <response>
  	<subject>test2</subject>
  	<location></location>
  	<dtstart>2017-03-21 08:00:00</dtstart>
  	<dtend>2017-03-21 09:00:00</dtend>
  	<id>uqnt090jvr0en3cqkctlj90qg8@google.com</id>
  	<priority>0</priority>
  </response>
  <response>
  	<subject>Scott recur mwf</subject>
  	<location></location>
  	<dtstart>2017-03-22 04:00:00</dtstart>
  	<dtend>2017-03-22 07:00:00</dtend>
  	<id>9huhq46274rrptseqtmp07al34@google.com</id>
  	<priority>0</priority>
  </response>

[SSzretter]

Your output for the non-recurring "test2" is correct at 8a-9a, but the recur mwf should be 8a-11a (not 4a-7a).

[u01jmg3]

• Using latest dev-master I get:

<response>
	<subject>test2</subject>
	<location></location>
	<dtstart>2017-03-21 08:00:00</dtstart>
	<dtend>2017-03-21 09:00:00</dtend>
	<id>uqnt090jvr0en3cqkctlj90qg8@google.com</id>
	<priority>0</priority>
</response>
<response>
	<subject>Scott recur mwf</subject>
	<location></location>
	<dtstart>2017-03-22 08:00:00</dtstart>
	<dtend>2017-03-22 11:00:00</dtend>
	<id>9huhq46274rrptseqtmp07al34@google.com</id>
	<priority>0</priority>
</response>

[SSzretter]

Looks good now, thank you

[u01jmg3]

Spot anything else just let me know - realise this has been a slog but I appreciate your help in fine tuning the parser.