Zookeeper::exists

(PECL zookeeper >= 0.1.0)

Zookeeper::exists — Checks the existence of a node in zookeeper synchronously

Beschreibung

public Zookeeper::exists ( string $path [, callable $watcher_cb = NULL ] ) : array

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.

Achtung

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