/**
* Get the value for the node
*
* @param string $path the path to the node
*
* @return string|null
*/
public function get($path)
{
if (!$this->zookeeper->exists($path)) {
return null;
}
return $this->zookeeper->get($path);
}
/**
* Get the currently active brokers participating in a particular topic.
*
* @param string $topic the topic to get the brokers for
*
* @return array an array of brokers (int) that are participating in the topic
*/
public function brokers($topic)
{
$topicPath = sprintf(self::TOPIC_PATH, $topic);
if (!$this->zookeeper->exists($topicPath)) {
return array();
}
$children = $this->zookeeper->getChildren($topicPath);
if (empty($children)) {
return array();
}
$results = array();
foreach ($children as $child) {
$results[] = intval(str_replace($topicPath, '', $child));
}
return $results;
}
/**
* Get the currently active brokers participating in a particular topic.
*
* @param string $topic the topic to get the brokers for
*
* @return array an array of brokers (int) that are participating in the topic
*/
public function brokers($topic)
{
$topicPath = sprintf(self::TOPIC_PATH, $topic);
if (!@$this->zookeeper->exists($topicPath)) {
if ($this->zookeeper->getState() != Zookeeper::CONNECTED_STATE) {
$msg = 'Cannot connect to Zookeeper to fetch brokers for topic ' . $topic;
throw new Kafka_Exception_ZookeeperConnection($msg);
}
return array();
}
$children = $this->zookeeper->getChildren($topicPath);
if (empty($children)) {
return array();
}
$results = array();
foreach ($children as $child) {
$results[] = intval(str_replace($topicPath, '', $child));
}
return $results;
}
function commitOffset($groupId, $topic, $brokerId, $partition, \Kafka\Offset $offset)
{
$this->zkConnect();
$path = "/consumers/{$groupId}/offsets/{$topic}";
if (!$this->zk->exists($path)) {
$this->createPermaNode($path);
}
if (!$this->zk->exists("{$path}/{$brokerId}-{$partition}")) {
$this->createPermaNode("{$path}/{$brokerId}-{$partition}", $offset->__toString());
} else {
$this->zk->set("{$path}/{$brokerId}-{$partition}", $offset->__toString());
}
}
/**
* Gets all the partitions for a given topic.
*
* @param string $topic the topic to get the partitions for
*
* @return array an associative array of the broker (int) to the number of partitions (int)
*/
public function partitions($topic)
{
$offsetsPath = sprintf(self::OFFSETS_PATH, $this->group, $topic);
if (!$this->zookeeper->exists($offsetsPath)) {
return array();
}
$children = $this->zookeeper->getChildren($offsetsPath);
$partitions = array();
foreach ($children as $child) {
list($broker, $partition) = explode('-', str_replace($offsetsPath, '', $child), 2);
$partitions[intval($broker)] = intval($partition);
}
return $partitions;
}
/**
* Wath a given path
* @param string $path the path to node
* @param callable $callback callback function
* @return string|null
*/
public function watch($path, $callback)
{
if (!is_callable($callback)) {
return null;
}
if ($this->zookeeper->exists($path)) {
if (!isset($this->callback[$path])) {
$this->callback[$path] = array();
}
if (!in_array($callback, $this->callback[$path])) {
$this->callback[$path][] = $callback;
return $this->zookeeper->get($path, array($this, 'watchCallback'));
}
}
}
/**
* Create parent node, if needed
*
* @param string $nodePath
*/
private function createParentIfNeeded($nodePath)
{
if (!$this->zk->exists($nodePath)) {
$this->zk->create($nodePath, 'Cruftflake machines', array(array('perms' => \Zookeeper::PERM_ALL, 'scheme' => 'world', 'id' => 'anyone')));
}
}
