/**
* Returns shardIDs of all shards storing groups this user belongs to
*/
public static function getUserGroupShards($userID)
{
$groupIDs = self::getUserGroups($userID);
if (!$groupIDs) {
return array();
}
$shardIDs = array();
foreach ($groupIDs as $groupID) {
$shardID = Zotero_Shards::getByGroupID($groupID);
$shardIDs[$shardID] = true;
}
return array_keys($shardIDs);
}