Sabre\DAV\Exception\UnsupportedMediaType: HTTP/1.1 415 Validation error in iCalendar: ATTACH MUST NOT appear more than once in a VALARM component

[LukasReschke]

On c.nc.c with @oparoz's calendar:

/var/www/html/3rdparty/sabre/dav/lib/CalDAV/Plugin.php - line 772: Sabre\CalDAV\Plugin->validateICalendar('BEGIN VCALENDAR...', 'calendars/olivi...', false, Object(Sabre\HTTP\Request), Object(Sabre\HTTP\Response), false)
[internal function] Sabre\CalDAV\Plugin->beforeWriteContent('calendars/olivi...', Object(OCA\DAV\CalDAV\CalendarObject), 'BEGIN VCALENDAR...', false)
/var/www/html/3rdparty/sabre/event/lib/EventEmitterTrait.php - line 105: call_user_func_array(Array, Array)
/var/www/html/3rdparty/sabre/dav/lib/DAV/Server.php - line 1127: Sabre\Event\EventEmitter->emit('beforeWriteCont...', Array)
/var/www/html/3rdparty/sabre/dav/lib/DAV/CorePlugin.php - line 513: Sabre\DAV\Server->updateFile('calendars/olivi...', 'BEGIN VCALENDAR...', NULL)
[internal function] Sabre\DAV\CorePlugin->httpPut(Object(Sabre\HTTP\Request), Object(Sabre\HTTP\Response))
/var/www/html/3rdparty/sabre/event/lib/EventEmitterTrait.php - line 105: call_user_func_array(Array, Array)
/var/www/html/3rdparty/sabre/dav/lib/DAV/Server.php - line 479: Sabre\Event\EventEmitter->emit('method PUT', Array)
/var/www/html/3rdparty/sabre/dav/lib/DAV/Server.php - line 254: Sabre\DAV\Server->invokeMethod(Object(Sabre\HTTP\Request), Object(Sabre\HTTP\Response))
/var/www/html/apps/dav/lib/Server.php - line 245: Sabre\DAV\Server->exec()
/var/www/html/apps/dav/appinfo/v2/remote.php - line 33: OCA\DAV\Server->exec()
/var/www/html/remote.php - line 162: require_once('/var/www/html/a...')
{main}

{"reqId":"mos7dqVkCSCcpuuI4nRg","level":4,"time":"2017-05-15T09:39:26+00:00","remoteAddr":"XXX","user":"olivier","app":"webdav","method":"PUT","url":"/remote.php/dav/calendars/olivier/vacations_shared_by_Nextcloud/20170418T171142Z-4f2b412a84c9a52d.ics","message":"Exception: {"Message":"HTTP\/1.1 415 Validation error in iCalendar: ATTACH MUST NOT appear more than once in a VALARM component","Exception":"Sabre\\DAV\\Exception\\UnsupportedMediaType","Code":0,"Trace":"#0 \/var\/www\/html\/3rdparty\/sabre\/dav\/lib\/CalDAV\/Plugin.php(772): Sabre\\CalDAV\\Plugin->validateICalendar('BEGIN:VCALENDAR...', 'calendars\/olivi...', false, Object(Sabre\\HTTP\\Request), Object(Sabre\\HTTP\\Response), false)\n#1 [internal function]: Sabre\\CalDAV\\Plugin->beforeWriteContent('calendars\/olivi...', Object(OCA\\DAV\\CalDAV\\CalendarObject), 'BEGIN:VCALENDAR...', false)\n#2 \/var\/www\/html\/3rdparty\/sabre\/event\/lib\/EventEmitterTrait.php(105): call_user_func_array(Array, Array)\n#3 \/var\/www\/html\/3rdparty\/sabre\/dav\/lib\/DAV\/Server.php(1127): Sabre\\Event\\EventEmitter->emit('beforeWriteCont...', Array)\n#4 \/var\/www\/html\/3rdparty\/sabre\/dav\/lib\/DAV\/CorePlugin.php(513): Sabre\\DAV\\Server->updateFile('calendars\/olivi...', 'BEGIN:VCALENDAR...', NULL)\n#5 [internal function]: Sabre\\DAV\\CorePlugin->httpPut(Object(Sabre\\HTTP\\Request), Object(Sabre\\HTTP\\Response))\n#6 \/var\/www\/html\/3rdparty\/sabre\/event\/lib\/EventEmitterTrait.php(105): call_user_func_array(Array, Array)\n#7 \/var\/www\/html\/3rdparty\/sabre\/dav\/lib\/DAV\/Server.php(479): Sabre\\Event\\EventEmitter->emit('method:PUT', Array)\n#8 \/var\/www\/html\/3rdparty\/sabre\/dav\/lib\/DAV\/Server.php(254): Sabre\\DAV\\Server->invokeMethod(Object(Sabre\\HTTP\\Request), Object(Sabre\\HTTP\\Response))\n#9 \/var\/www\/html\/apps\/dav\/lib\/Server.php(245): Sabre\\DAV\\Server->exec()\n#10 \/var\/www\/html\/apps\/dav\/appinfo\/v2\/remote.php(33): OCA\\DAV\\Server->exec()\n#11 \/var\/www\/html\/remote.php(162): require_once('\/var\/www\/html\/a...')\n#12 {main}","File":"\/var\/www\/html\/3rdparty\/sabre\/dav\/lib\/CalDAV\/Plugin.php","Line":917,"User":"olivier"}","userAgent":"Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 Lightning/4.7.8","version":"12.0.0.18"}

[enoch85]

Is this to any help maybe? nextcloud/contacts#206

[georgehrke]

Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 Lightning/4.7.8

Looks like Lightning is producing non-standard-compliant ics data.

From RFC 5545 3.8.1.1:

Conformance: This property can be specified multiple times in a
"VEVENT", "VTODO", "VJOURNAL", or "VALARM" calendar component with
the exception of AUDIO alarm that only allows this property to
occur once.

[georgehrke]

@MorrisJobke @rullzer
I guess this is a general question we need to discuss:

• be very strict and return error messages when calendar data is incorrect
  or
• be forgiving and also accept calendar (/addressbook data), thats parseable, but technically invalid

The latter will force us to revisit every manipulation / check of calendar data on the server, because certain presumptions we have now (because we are so strict), may not be the case when we are more forgiving.

[enoch85]

@georgehrke For Thunderbird I recommend Cardbook, I even think it's documented in the Nextcloud documentation.

[enoch85]

Yup it is: https://docs.nextcloud.com/server/12/user_manual/pim/sync_thunderbird.html

[georgehrke]

But this is about Lightning and CalDAV 😉
Although similar errors, as you pointed out, may occur for CardDAV.

[mfechner]

I see the same problem.
Get a calendar alarm display in Thunderbird and snooze it for one day, that next day it is displayed you cannot close it anymore.

[georgehrke]

@mfechner Please report this bug to Lightning. As the error report says, there is a validation error in the calendar data => Thunderbird is not sending valid ics data.

(Would be great if you could post a link to the mozilla bug tracker afterwards for reference.)

[kesselb]

Why is this a lightning issue?

"ATTACH MUST NOT appear more than once in a VALARM"

Conformance: This property can be specified multiple times in a "VEVENT", "VTODO", "VJOURNAL", or "VALARM" calendar component

[georgehrke]

@danielkesselberg Please don't withhold the last part of the sentence:

  Conformance:  This property can be specified multiple times in a
      "VEVENT", "VTODO", "VJOURNAL", or "VALARM" calendar component with
      the exception of AUDIO alarm that only allows this property to
      occur once.

[kesselb]

Could be related https://bugzilla.mozilla.org/show_bug.cgi?id=1460001

[skjnldsv]

Most likely.
Bug is closed, let's close here as well. Never seen this issue happening again so far.