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Zookeeper::exists

PHP function Edit on GitHub ✎

(PECL zookeeper >= 0.1.0)

Checks the existence of a node in zookeeper synchronously

Description

Zookeeper::exists(string $path, callable $watcher_cb = null): array

Parameters

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

Return Values

Returns the value of stat for the path if the given node exists, otherwise false.

Errors/Exceptions

This method emits PHP error/warning when parameters count or types are wrong or fail to check the existence of a node.

Caution

Since version 0.3.0, this method emits ZookeeperException and its derivatives.

Examples

Zookeeper::exists example

Check the existence of a node.

php

<?php
$zookeeper = new Zookeeper('localhost:2181');
$path = '/path/to/node';
$r = $zookeeper->exists($path);
if ($r)
  echo 'EXISTS';
else
  echo 'N/A or ERR';
?>

The above example will output:

output

EXISTS