Zookeeper::exists
(PECL zookeeper >= 0.1.0)
Zookeeper::exists — Checks the existence of a node in zookeeper synchronously
Beschreibung
Parameter-Liste
-
path
-
The name of the node. Expressed as a file name with slashes separating ancestors of the node.
-
watcher_cb
-
if nonzero, a watch will be set at the server to notify the client if the node changes. The watch will be set even if the node does not
Rückgabewerte
Returns the value of stat for the path if the given node exists, otherwise false.
Fehler/Exceptions
This method emits PHP error/warning when parameters count or types are wrong or fail to check the existence of a node.
Since version 0.3.0, this method emits ZookeeperException and it's derivatives.
Beispiele
Beispiel #1 Zookeeper::exists() example
Check the existence of a node.
<?php
$zookeeper = new Zookeeper('locahost:2181');
$path = '/path/to/node';
$r = $zookeeper->exists($path);
if ($r)
echo 'EXISTS';
else
echo 'N/A or ERR';
?>
Das oben gezeigte Beispiel erzeugt folgende Ausgabe:
EXISTS
Siehe auch
- Zookeeper::get() - Gets the data associated with a node synchronously
- ZookeeperException