mirror of
https://github.com/EGroupware/egroupware.git
synced 2024-11-23 16:33:17 +01:00
683 lines
19 KiB
PHP
683 lines
19 KiB
PHP
<?php
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/**
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* EGroupware: GroupDAV access: abstract baseclass for groupdav/caldav/carddav handlers
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*
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* @link http://www.egroupware.org
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* @license http://opensource.org/licenses/gpl-license.php GPL - GNU General Public License
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* @package api
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* @subpackage groupdav
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* @author Ralf Becker <RalfBecker-AT-outdoor-training.de>
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* @copyright (c) 2007-12 by Ralf Becker <RalfBecker-AT-outdoor-training.de>
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* @version $Id$
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*/
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/**
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* EGroupware: GroupDAV access: abstract baseclass for groupdav/caldav/carddav handlers
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*/
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abstract class groupdav_handler
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{
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/**
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* Debug level: 0 = nothing, 1 = function calls, 2 = more info, eg. complete $_SERVER array
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*
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* The debug messages are send to the apache error_log
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*
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* @var integer
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*/
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var $debug = 0;
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/**
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* eGW's charset
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*
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* @var string
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*/
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var $egw_charset;
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/**
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* Reference to the accounts class
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*
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* @var accounts
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*/
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var $accounts;
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/**
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* Reference to the ACL class
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*
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* @var acl
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*/
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var $acl;
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/**
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* Translates method names into ACL bits
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*
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* @var array
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*/
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var $method2acl = array(
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'GET' => EGW_ACL_READ,
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'PUT' => EGW_ACL_EDIT,
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'DELETE' => EGW_ACL_DELETE,
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);
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/**
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* eGW application responsible for the handler
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*
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* @var string
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*/
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var $app;
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/**
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* Calling groupdav object
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*
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* @var groupdav
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*/
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var $groupdav;
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/**
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* Base url of handler, need to prefix all pathes not automatic handled by HTTP_WebDAV_Server
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*
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* @var string
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*/
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var $base_uri;
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/**
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* HTTP_IF_MATCH / etag of current request / last call to _common_get_put_delete() method
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*
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* @var string
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*/
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var $http_if_match;
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/**
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* Identified user agent
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*
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* @var string
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*/
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var $agent;
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/**
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* Extension to append to url/path
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*
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* @var string
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*/
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static $path_extension = '.ics';
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/**
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* Which attribute to use to contruct name part of url/path
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*
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* @var string
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*/
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static $path_attr = 'id';
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/**
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* Constructor
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*
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* @param string $app 'calendar', 'addressbook' or 'infolog'
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* @param groupdav $groupdav calling class
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*/
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function __construct($app, groupdav $groupdav)
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{
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$this->app = $app;
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if (!is_null($parent->debug)) $this->debug = $groupdav->debug;
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$this->base_uri = $groupdav->base_uri;
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$this->groupdav = $groupdav;
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$this->agent = self::get_agent();
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$this->egw_charset = translation::charset();
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$this->accounts = $GLOBALS['egw']->accounts;
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$this->acl = $GLOBALS['egw']->acl;
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}
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/**
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* Handle propfind request for an application folder
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*
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* @param string $path
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* @param array $options
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* @param array &$files
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* @param int $user account_id
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* @return mixed boolean true on success, false on failure or string with http status (eg. '404 Not Found')
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*/
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abstract function propfind($path,$options,&$files,$user);
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/**
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* Propfind callback, if interator is used
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*
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* @param string $path
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* @param array $filter
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* @param array|boolean $start false=return all or array(start,num)
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* @param int &$total
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* @return array with "files" array with values for keys path and props
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*/
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function &propfind_callback($path, array $filter,$start,&$total) { }
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/**
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* Handle get request for an applications entry
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*
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* @param array &$options
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* @param int $id
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* @param int $user=null account_id
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* @return mixed boolean true on success, false on failure or string with http status (eg. '404 Not Found')
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*/
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abstract function get(&$options,$id,$user=null);
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/**
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* Handle get request for an applications entry
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*
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* @param array &$options
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* @param int $id
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* @param int $user=null account_id of owner, default null
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* @return mixed boolean true on success, false on failure or string with http status (eg. '404 Not Found')
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*/
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abstract function put(&$options,$id,$user=null);
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/**
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* Handle get request for an applications entry
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*
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* @param array &$options
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* @param int $id
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* @return mixed boolean true on success, false on failure or string with http status (eg. '404 Not Found')
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*/
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abstract function delete(&$options,$id);
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/**
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* Read an entry
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*
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* @param string/int $id
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* @return array/boolean array with entry, false if no read rights, null if $id does not exist
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*/
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abstract function read($id);
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/**
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* Check if user has the neccessary rights on an entry
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*
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* @param int $acl EGW_ACL_READ, EGW_ACL_EDIT or EGW_ACL_DELETE
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* @param array/int $entry entry-array or id
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* @return boolean null if entry does not exist, false if no access, true if access permitted
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*/
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abstract function check_access($acl,$entry);
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/**
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* Add extra properties for collections
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*
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* @param array $props=array() regular props by the groupdav handler
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* @param string $displayname
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* @param string $base_uri=null base url of handler
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* @param int $user=null account_id of owner of collection
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* @return array
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*/
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public function extra_properties(array $props=array(), $displayname, $base_uri=null, $user=null)
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{
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return $props;
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}
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/**
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* Get the etag for an entry, can be reimplemented for other algorithm or field names
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*
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* @param array/int $event array with event or cal_id
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* @return string/boolean string with etag or false
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*/
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function get_etag($entry)
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{
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if (!is_array($entry))
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{
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$entry = $this->read($entry);
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}
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if (!is_array($entry) || !isset($entry['id']) || !(isset($entry['modified']) || isset($entry['etag'])))
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{
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// error_log(__METHOD__."(".array2string($entry).") Cant create etag!");
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return false;
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}
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return $entry['id'].':'.(isset($entry['etag']) ? $entry['etag'] : $entry['modified']);
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}
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/**
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* Convert etag to the raw etag column value (without quotes, double colon and id)
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*
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* @param string $etag
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* @return int
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*/
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static function etag2value($etag)
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{
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list(,$val) = explode(':',$etag,2);
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return $val;
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}
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/**
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* Handle common stuff for get, put and delete requests:
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* - application rights
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* - entry level acl, incl. edit and delete rights
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* - etag handling for precondition failed and not modified
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*
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* @param string $method GET, PUT, DELETE
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* @param array &$options
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* @param int|string &$id on return self::$path_extension got removed
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* @param boolean &$return_no_access=false if set to true on call, instead of '403 Forbidden' the entry is returned and $return_no_access===false
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* @param boolean $ignore_if_match=false if true, ignore If-Match precondition
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* @return array|string entry on success, string with http-error-code on failure, null for PUT on an unknown id
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*/
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function _common_get_put_delete($method,&$options,&$id,&$return_no_access=false,$ignore_if_match=false)
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{
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if (self::$path_extension) $id = basename($id,self::$path_extension);
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if ($this->app != 'principals' && !$GLOBALS['egw_info']['user']['apps'][$this->app])
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{
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if ($this->debug) error_log(__METHOD__."($method,,$id) 403 Forbidden: no app rights for '$this->app'");
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return '403 Forbidden'; // no app rights
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}
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$extra_acl = $this->method2acl[$method];
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if (!($entry = $this->read($id)) && ($method != 'PUT' || $entry === false) ||
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($extra_acl != EGW_ACL_READ && $this->check_access($extra_acl,$entry) === false))
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{
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if ($return_no_access && !is_null($entry))
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{
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if ($this->debug) error_log(__METHOD__."($method,,$id,$return_no_access) \$entry=".array2string($entry).", \$return_no_access set to false");
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$return_no_access = false;
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}
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else
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{
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if ($this->debug) error_log(__METHOD__."($method,,$id) 403 Forbidden/404 Not Found: read($id)==".($entry===false?'false':'null'));
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return !is_null($entry) ? '403 Forbidden' : '404 Not Found';
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}
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}
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if ($entry)
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{
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$etag = $this->get_etag($entry);
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// If the clients sends an "If-Match" header ($_SERVER['HTTP_IF_MATCH']) we check with the current etag
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// of the calendar --> on failure we return 412 Precondition failed, to not overwrite the modifications
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if (isset($_SERVER['HTTP_IF_MATCH']) && !$ignore_if_match)
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{
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$this->http_if_match = $_SERVER['HTTP_IF_MATCH'];
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// strip of quotes around etag, if they exist, that way we allow etag with and without quotes
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if ($this->http_if_match[0] == '"') $this->http_if_match = substr($this->http_if_match, 1, -1);
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if ($this->http_if_match !== $etag)
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{
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if ($this->debug) error_log(__METHOD__."($method,,$id) HTTP_IF_MATCH='$_SERVER[HTTP_IF_MATCH]', etag='$etag': 412 Precondition failed");
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return '412 Precondition Failed';
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}
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}
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if (isset($_SERVER['HTTP_IF_NONE_MATCH']))
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{
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$if_none_match = $_SERVER['HTTP_IF_NONE_MATCH'];
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// strip of quotes around etag, if they exist, that way we allow etag with and without quotes
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if ($if_none_match[0] == '"') $if_none_match = substr($if_none_match, 1, -1);
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// if an IF_NONE_MATCH is given, check if we need to send a new export, or the current one is still up-to-date
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if (in_array($method, array('GET','HEAD')) && $etag === $if_none_match)
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{
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if ($this->debug) error_log(__METHOD__."($method,,$id) HTTP_IF_NONE_MATCH='$_SERVER[HTTP_IF_NONE_MATCH]', etag='$etag': 304 Not Modified");
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return '304 Not Modified';
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}
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if ($method == 'PUT' && ($if_none_match == '*' || $if_none_match == $etag))
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{
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if ($this->debug) error_log(__METHOD__."($method,,$id) HTTP_IF_NONE_MATCH='$_SERVER[HTTP_IF_NONE_MATCH]', etag='$etag': 412 Precondition failed");
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return '412 Precondition Failed';
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}
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}
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}
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return $entry;
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}
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/**
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* Get the handler for the given app
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*
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* @static
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* @param string $app 'calendar', 'addressbook' or 'infolog'
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* @param groupdav $groupdav calling class
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* @return groupdav_handler
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*/
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static function app_handler($app, $groupdav)
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{
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static $handler_cache = array();
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if (!array_key_exists($app,$handler_cache))
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{
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$class = $app.'_groupdav';
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if (!class_exists($class) && !class_exists($class = 'groupdav_'.$app)) return null;
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$handler_cache[$app] = new $class($app, $groupdav);
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}
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if ($debug) error_log(__METHOD__."('$app')");
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return $handler_cache[$app];
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}
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/**
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* Identify know GroupDAV agents by HTTP_USER_AGENT header
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*
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* @return string|boolean agent name or false
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*/
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static function get_agent()
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{
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static $agent;
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if (is_null($agent))
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{
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$agent = false;
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// identify the agent (GroupDAV client) from the HTTP_USER_AGENT header
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$user_agent = strtolower($_SERVER['HTTP_USER_AGENT']);
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foreach(array(
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'iphone' => 'iphone', // Apple iPhone iCal
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'davkit' => 'davkit', // Apple iCal 10.6
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'coredav' => 'coredav', // Apple iCal 10.7
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'calendarstore' => 'calendarstore', // Apple iCal 5.0.1 under OS X 10.7.2
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'dataaccess' => 'dataaccess', // Apple addressbook iPhone
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'cfnetwork' => 'cfnetwork', // Apple Addressbook 10.6/7
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'bionicmessage.net' => 'funambol', // funambol GroupDAV connector from bionicmessage.net
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'zideone' => 'zideone', // zideone outlook plugin
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'lightning' => 'lightning', // Lighting (SOGo connector for addressbook)
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'webkit' => 'webkit', // Webkit Browser (also reports KHTML!)
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'akonadi' => 'akonadi', // new KDE PIM framework (also reports KHTML!)
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'khtml' => 'kde', // KDE clients
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'neon' => 'neon',
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'ical4ol' => 'ical4ol', // iCal4OL client
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'evolution' => 'evolution', // Evolution
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) as $pattern => $name)
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{
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if (strpos($user_agent,$pattern) !== false)
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{
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$agent = $name;
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break;
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}
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}
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if (!$agent)
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{
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//error_log("Unrecogniced GroupDAV client: HTTP_USER_AGENT='$_SERVER[HTTP_USER_AGENT]'!");
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}
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else
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{
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switch ($agent)
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{
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case 'cfnetwork':
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if (preg_match('/address%20book\/([0-9.]+)/', $user_agent, $matches))
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{
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if ((int)$matches[1] < 868) $agent .= '_old';
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}
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break;
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case 'kde':
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// Akonadi (new KDE Pim framework) unfortunately has same user-agent as old kde
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// we can only assume KDE 4.7+ uses Akonadi native resource, while below this was not available
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// Unfortunately the old pre-Akonadi GroupDAV resource can still be used, but we have no way of detecting it
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if (preg_match('/KHTML\/([0-9.]+)/', $_SERVER['HTTP_USER_AGENT'], $matches) && (float)$matches[1] >= 4.7)
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{
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$agent = 'akonadi';
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}
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break;
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}
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}
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}
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if ($debug) error_log(__METHOD__."GroupDAV client: $agent");
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return $agent;
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}
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/**
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* Return priviledges for current user, default is read and read-current-user-privilege-set
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*
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* Priviledges are for the collection, not the resources / entries!
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*
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* @param string $path path of collection
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* @param int $user=null owner of the collection, default current user
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* @return array with privileges
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*/
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public function current_user_privileges($path, $user=null)
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{
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static $grants;
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if (is_null($grants))
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{
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$grants = $this->acl->get_grants($this->app, $this->app != 'addressbook');
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}
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$priviledes = array('read-current-user-privilege-set' => 'read-current-user-privilege-set');
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if (!$user || $grants[$user] & EGW_ACL_READ)
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{
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$priviledes['read'] = 'read';
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// allows on all calendars/addressbooks to write properties, as we store them on a per-user basis
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// and only allow to modify explicit named properties in CalDAV, CardDAV or Calendarserver name-space
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$priviledes['write-properties'] = 'write-properties';
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}
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if (!$user || $grants[$user] & EGW_ACL_ADD)
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{
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$priviledes['bind'] = 'bind'; // PUT for new resources
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}
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if (!$user || $grants[$user] & EGW_ACL_EDIT)
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{
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$priviledes['write-content'] = 'write-content'; // otherwise iOS calendar does not allow to add events
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}
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if (!$user || $grants[$user] & EGW_ACL_DELETE)
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{
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$priviledes['unbind'] = 'unbind'; // DELETE
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}
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// copy/move of existing resources might require write-properties, thought we do not support an explicit PROPATCH
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return $priviledes;
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}
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/**
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* Create the path/name for an entry
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*
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* @param array $entry
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* @return string
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*/
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function get_path($entry)
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{
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return $entry[self::$path_attr].self::$path_extension;
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}
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/**
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* Return calendars/addressbooks shared from other users with the current one
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*
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* return array account_id => account_lid pairs
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*/
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function get_shared()
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{
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return array();
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}
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/**
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* Add a resource
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*
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* @param string $path path of collection, NOT entry!
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* @param array $entry
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* @param array $props
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* @return array with values for keys 'path' and 'props'
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*/
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public function add_resource($path, array $entry, array $props)
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{
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foreach(array(
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'getetag' => $this->get_etag($entry),
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'getcontenttype' => 'text/calendar',
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'getlastmodified' => $entry['modified'],
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'displayname' => $entry['title'],
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) as $name => $value)
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{
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if (!isset($props[$name]))
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{
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$props[$name] = $value;
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}
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}
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// if requested add privileges
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$privileges = array('read', 'read-current-user-privilege-set');
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if ($this->groupdav->prop_requested('current-user-privilege-set') === true && !isset($props['current-user-privilege-set']))
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{
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if ($this->check_access(EGW_ACL_EDIT, $entry))
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{
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$privileges[] = 'write-content';
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}
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}
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if ($this->groupdav->prop_requested('owner') === true && !isset($props['owner']) &&
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($account_lid = $this->accounts->name2id($entry['owner'])))
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{
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$type = $this->accounts->get_type($entry['owner']) == 'u' ? 'users' : 'groups';
|
|
$props['owner'] = HTTP_WebDAV_Server::mkprop('href', $this->base_uri.'/principals/'.$type.'/'.$account_lid.'/');
|
|
}
|
|
// we urldecode here, as HTTP_WebDAV_Server uses a minimal (#?%) urlencoding for incomming pathes and urlencodes pathes in propfind
|
|
return $this->groupdav->add_resource($path.urldecode($this->get_path($entry)), $props, $privileges);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Iterator for propfinds using propfind callback of a groupdav_handler to query results in chunks
|
|
*
|
|
* The propfind method just computes a filter and then returns an instance of this iterator instead of the files:
|
|
*
|
|
* function propfind($path,$options,&$files,$user,$id='')
|
|
* {
|
|
* $filter = array();
|
|
* // compute filter from path, options, ...
|
|
*
|
|
* $files['files'] = new groupdav_propfind_iterator($this,$filter,$files['files']);
|
|
*
|
|
* return true;
|
|
* }
|
|
*/
|
|
class groupdav_propfind_iterator implements Iterator
|
|
{
|
|
/**
|
|
* current path
|
|
*
|
|
* @var string
|
|
*/
|
|
protected $path;
|
|
|
|
/**
|
|
* Handler to call for entries
|
|
*
|
|
* @var groupdav_handler
|
|
*/
|
|
protected $handler;
|
|
|
|
/**
|
|
* Filter of propfind call
|
|
*
|
|
* @var array
|
|
*/
|
|
protected $filter;
|
|
|
|
/**
|
|
* Extra responses to return too
|
|
*
|
|
* @var array
|
|
*/
|
|
protected $common_files;
|
|
|
|
/**
|
|
* current chunk
|
|
*
|
|
* @var array
|
|
*/
|
|
protected $files;
|
|
|
|
|
|
/**
|
|
* Start value for callback
|
|
*
|
|
* @var int
|
|
*/
|
|
protected $start=0;
|
|
|
|
/**
|
|
* Number of entries queried from callback in one call
|
|
*
|
|
*/
|
|
const CHUNK_SIZE = 500;
|
|
|
|
/**
|
|
* Log calls via error_log()
|
|
*
|
|
* @var boolean
|
|
*/
|
|
public $debug = false;
|
|
|
|
/**
|
|
|
|
/**
|
|
* Constructor
|
|
*
|
|
* @param groupdav_handler $handler
|
|
* @param array $filter filter for propfind call
|
|
* @param array $files=array() extra files/responses to return too
|
|
*/
|
|
public function __construct(groupdav_handler $handler, $path, array $filter,array &$files=array())
|
|
{
|
|
if ($this->debug) error_log(__METHOD__."('$path', ".array2string($filter).",)");
|
|
$this->path = $path;
|
|
$this->handler = $handler;
|
|
$this->filter = $filter;
|
|
$this->files = $this->common_files = $files;
|
|
reset($this->files);
|
|
}
|
|
|
|
/**
|
|
* Return the current element
|
|
*
|
|
* @return array
|
|
*/
|
|
public function current()
|
|
{
|
|
if ($this->debug) error_log(__METHOD__."() returning ".array2string(current($this->files)));
|
|
return current($this->files);
|
|
}
|
|
|
|
/**
|
|
* Return the key of the current element
|
|
*
|
|
* @return int|string
|
|
*/
|
|
public function key()
|
|
{
|
|
$current = current($this->files);
|
|
|
|
if ($this->debug) error_log(__METHOD__."() returning ".array2string($current['path']));
|
|
return $current['path']; // we return path as key
|
|
}
|
|
|
|
/**
|
|
* Move forward to next element (called after each foreach loop)
|
|
*/
|
|
public function next()
|
|
{
|
|
if (next($this->files) !== false)
|
|
{
|
|
if ($this->debug) error_log(__METHOD__."() returning TRUE");
|
|
return true;
|
|
}
|
|
// check if previous query gave less then CHUNK_SIZE entries --> we're done
|
|
if ($this->start && count($this->files) < self::CHUNK_SIZE)
|
|
{
|
|
if ($this->debug) error_log(__METHOD__."() returning FALSE (no more entries)");
|
|
return false;
|
|
}
|
|
// try query further files via propfind callback of handler and store result in $this->files
|
|
$this->files = $this->handler->propfind_callback($this->path,$this->filter,array($this->start,self::CHUNK_SIZE));
|
|
if (!is_array($this->files) || !($entries = count($this->files)))
|
|
{
|
|
if ($this->debug) error_log(__METHOD__."() returning FALSE (no more entries)");
|
|
return false; // no further entries
|
|
}
|
|
$this->start += self::CHUNK_SIZE;
|
|
reset($this->files);
|
|
|
|
if ($this->debug) error_log(__METHOD__."() this->start=$this->start, entries=$entries, count(this->files)=".count($this->files)." returning ".array2string(current($this->files) !== false));
|
|
|
|
return current($this->files) !== false;
|
|
}
|
|
|
|
/**
|
|
* Rewind the Iterator to the first element (called at beginning of foreach loop)
|
|
*/
|
|
public function rewind()
|
|
{
|
|
if ($this->debug) error_log(__METHOD__."()");
|
|
|
|
$this->start = 0;
|
|
$this->files = $this->common_files;
|
|
if (!$this->files) $this->next(); // otherwise valid will return false and nothing get returned
|
|
reset($this->files);
|
|
}
|
|
|
|
/**
|
|
* Checks if current position is valid
|
|
*
|
|
* @return boolean
|
|
*/
|
|
public function valid ()
|
|
{
|
|
if ($this->debug) error_log(__METHOD__."() returning ".array2string(current($this->files) !== false));
|
|
return current($this->files) !== false;
|
|
}
|
|
}
|