<?php
namespace Sabre\CalDAV\Backend;
use Sabre\VObject;
use Sabre\CalDAV;
/**
* Abstract Calendaring backend. Extend this class to create your own backends.
*
* Checkout the BackendInterface for all the methods that must be implemented.
*
* @copyright Copyright (C) fruux GmbH (https://fruux.com/)
* @author Evert Pot (http://evertpot.com/)
* @license http://sabre.io/license/ Modified BSD License
*/
abstract class AbstractBackend implements BackendInterface {
/**
* Updates properties for a calendar.
*
* The list of mutations is stored in a Sabre\DAV\PropPatch object.
* To do the actual updates, you must tell this object which properties
* you're going to process with the handle() method.
*
* Calling the handle method is like telling the PropPatch object "I
* promise I can handle updating this property".
*
* Read the PropPatch documenation for more info and examples.
*
* @param string $path
* @param \Sabre\DAV\PropPatch $propPatch
* @return void
*/
function updateCalendar($calendarId, \Sabre\DAV\PropPatch $propPatch) {
}
/**
* Returns a list of calendar objects.
*
* This method should work identical to getCalendarObject, but instead
* return all the calendar objects in the list as an array.
*
* If the backend supports this, it may allow for some speed-ups.
*
* @param mixed $calendarId
* @param array $uris
* @return array
*/
function getMultipleCalendarObjects($calendarId, array $uris) {
return array_map(function($uri) use ($calendarId) {
return $this->getCalendarObject($calendarId, $uri);
}, $uris);
}
/**
* Performs a calendar-query on the contents of this calendar.
*
* The calendar-query is defined in RFC4791 : CalDAV. Using the
* calendar-query it is possible for a client to request a specific set of
* object, based on contents of iCalendar properties, date-ranges and
* iCalendar component types (VTODO, VEVENT).
*
* This method should just return a list of (relative) urls that match this
* query.
*
* The list of filters are specified as an array. The exact array is
* documented by \Sabre\CalDAV\CalendarQueryParser.
*
* Note that it is extremely likely that getCalendarObject for every path
* returned from this method will be called almost immediately after. You
* may want to anticipate this to speed up these requests.
*
* This method provides a default implementation, which parses *all* the
* iCalendar objects in the specified calendar.
*
* This default may well be good enough for personal use, and calendars
* that aren't very large. But if you anticipate high usage, big calendars
* or high loads, you are strongly adviced to optimize certain paths.
*
* The best way to do so is override this method and to optimize
* specifically for 'common filters'.
*
* Requests that are extremely common are:
* * requests for just VEVENTS
* * requests for just VTODO
* * requests with a time-range-filter on either VEVENT or VTODO.
*
* ..and combinations of these requests. It may not be worth it to try to
* handle every possible situation and just rely on the (relatively
* easy to use) CalendarQueryValidator to handle the rest.
*
* Note that especially time-range-filters may be difficult to parse. A
* time-range filter specified on a VEVENT must for instance also handle
* recurrence rules correctly.
* A good example of how to interprete all these filters can also simply
* be found in \Sabre\CalDAV\CalendarQueryFilter. This class is as correct
* as possible, so it gives you a good idea on what type of stuff you need
* to think of.
*
* @param mixed $calendarId
* @param array $filters
* @return array
*/
function calendarQuery($calendarId, array $filters) {
$result = [];
$objects = $this->getCalendarObjects($calendarId);
foreach ($objects as $object) {
if ($this->validateFilterForObject($object, $filters)) {
$result[] = $object['uri'];
}
}
return $result;
}
/**
* This method validates if a filter (as passed to calendarQuery) matches
* the given object.
*
* @param array $object
* @param array $filters
* @return bool
*/
protected function validateFilterForObject(array $object, array $filters) {
// Unfortunately, setting the 'calendardata' here is optional. If
// it was excluded, we actually need another call to get this as
// well.
if (!isset($object['calendardata'])) {
$object = $this->getCalendarObject($object['calendarid'], $object['uri']);
}
$vObject = VObject\Reader::read($object['calendardata']);
$validator = new CalDAV\CalendarQueryValidator();
$result = $validator->validate($vObject, $filters);
// Destroy circular references so PHP will GC the object.
$vObject->destroy();
return $result;
}
/**
* Searches through all of a users calendars and calendar objects to find
* an object with a specific UID.
*
* This method should return the path to this object, relative to the
* calendar home, so this path usually only contains two parts:
*
* calendarpath/objectpath.ics
*
* If the uid is not found, return null.
*
* This method should only consider * objects that the principal owns, so
* any calendars owned by other principals that also appear in this
* collection should be ignored.
*
* @param string $principalUri
* @param string $uid
* @return string|null
*/
function getCalendarObjectByUID($principalUri, $uid) {
// Note: this is a super slow naive implementation of this method. You
// are highly recommended to optimize it, if your backend allows it.
foreach ($this->getCalendarsForUser($principalUri) as $calendar) {
// We must ignore calendars owned by other principals.
if ($calendar['principaluri'] !== $principalUri) {
continue;
}
// Ignore calendars that are shared.
if (isset($calendar['{http://sabredav.org/ns}owner-principal']) && $calendar['{http://sabredav.org/ns}owner-principal'] !== $principalUri) {
continue;
}
$results = $this->calendarQuery(
$calendar['id'],
[
'name' => 'VCALENDAR',
'prop-filters' => [],
'comp-filters' => [
[
'name' => 'VEVENT',
'is-not-defined' => false,
'time-range' => null,
'comp-filters' => [],
'prop-filters' => [
[
'name' => 'UID',
'is-not-defined' => false,
'time-range' => null,
'text-match' => [
'value' => $uid,
'negate-condition' => false,
'collation' => 'i;octet',
],
'param-filters' => [],
],
]
]
],
]
);
if ($results) {
// We have a match
return $calendar['uri'] . '/' . $results[0];
}
}
}
}
