/**
* returns a collection of objects
*
* @param string $class the class of objects to fetch
* @param string $url (optional) the URL to retrieve
* @param mixed $parent (optional) the parent service/object
* @param array $parm (optional) array of key/value pairs to use as
* query strings
* @return \OpenCloud\Collection
*/
public function Collection($class, $url = NULL, $parent = NULL, $parm = array())
{
// set the element name
$collection = $class::JsonCollectionName();
$element = $class::JsonCollectionElement();
//$jsonname = $class::JsonName();
// save the parent
if (!isset($parent)) {
$parent = $this;
}
// determine the URL
if (!$url) {
$url = $parent->Url($class::ResourceName());
}
// add query string parameters
if (count($parm)) {
$url .= '?' . $this->MakeQueryString($parm);
}
// save debug info
$this->debug('%s:Collection(%s, %s, %s)', get_class($this), $url, $class, $collection);
// fetch the list
$response = $this->Request($url);
$this->debug('response %d [%s]', $response->HttpStatus(), $response->HttpBody());
// check return code
if ($response->HttpStatus() > 204) {
throw new \OpenCloud\CollectionError(sprintf(_('Unable to retrieve [%s] list from [%s], ' . 'status [%d] response [%s]'), $class, $url, $response->HttpStatus(), $response->HttpBody()));
}
// handle empty response
if (strlen($response->HttpBody()) == 0) {
return new Collection($parent, $class, array());
}
// parse the return
$obj = json_decode($response->HttpBody());
if ($this->CheckJsonError()) {
return FALSE;
}
// see if there is a "next" link
if (isset($obj->links)) {
if (is_array($obj->links)) {
foreach ($obj->links as $link) {
if (isset($link->rel) && $link->rel == 'next') {
if (isset($link->href)) {
$next_page_url = $link->href;
} else {
throw new \OpenCloud\DomainError(_('unexpected [links] found with no [href]'));
}
}
}
}
}
// and say goodbye
if (!$collection) {
$coll_obj = new Collection($parent, $class, $obj);
} elseif (isset($obj->{$collection})) {
if (!$element) {
$coll_obj = new Collection($parent, $class, $obj->{$collection});
} else {
// handle element levels
$arr = array();
foreach ($obj->{$collection} as $index => $item) {
$arr[] = $item->{$element};
}
$coll_obj = new Collection($parent, $class, $arr);
}
} else {
$coll_obj = new Collection($parent, $class, array());
}
// if there's a $next_page_url, then we need to establish a
// callback method
if (isset($next_page_url)) {
$coll_obj->SetNextPageCallback(array($this, 'Collection'), $next_page_url);
}
return $coll_obj;
}
