PHP マニュアル: Gets the data associated with a node synchronously

説明

public string Zookeeper::get(
    string $path,
    callable $watcher_cb = null,
    array &$stat = null,
    int $max_size = 0
)

パラメータ

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.
stat: If not NULL, will hold the value of stat for the path on return.
max_size: Max size of the data. If 0 is used, this method will return the whole data.

戻り値

Returns the data on success, and false on failure.

エラー / 例外

This method emits PHP error/warning when parameters count or types are wrong or fail to get value from node.

警告

Since version 0.3.0, this method emits ZookeeperException and it's derivatives.

例

例1 Zookeeper::get example

Get value from node.

<?php
$zookeeper = new Zookeeper('locahost:2181');
$path = '/path/to/node';
$value = 'nodevalue';
$zookeeper->set($path, $value);

$r = $zookeeper->get($path);
if ($r)
  echo $r;
else
  echo 'ERR';
?>

上の例の出力は以下となります。

nodevalue

例2 Zookeeper::get stat example

Get node stat info.

<?php
$zookeeper = new Zookeeper('localhost:2181');
$path = '/path/to/node';
$stat = [];
$zookeeper->get($path, null, $stat);
var_dump($stat);
?>

上の例の出力は以下となります。

array(11) {
  ["czxid"]=>
  float(0)
  ["mzxid"]=>
  float(0)
  ["ctime"]=>
  float(0)
  ["mtime"]=>
  float(0)
  ["version"]=>
  int(0)
  ["cversion"]=>
  int(-2)
  ["aversion"]=>
  int(0)
  ["ephemeralOwner"]=>
  float(0)
  ["dataLength"]=>
  int(0)
  ["numChildren"]=>
  int(2)
  ["pzxid"]=>
  float(0)
}

参考

Zookeeper::set
ZookeeperException