ZooKeeper

Table of Contents

Introduction
Installing/Configuring
Predefined Constants
ZooKeeper — The ZooKeeper class
- Zookeeper::addAuth — Specify application credentials.
- Zookeeper::connect — Create a handle to used communicate with zookeeper.
- Zookeeper::__construct — Create a handle to used communicate with zookeeper.
- Zookeeper::create — Create a node synchronously.
- Zookeeper::delete — Delete a node in zookeeper synchronously.
- Zookeeper::exists — Checks the existence of a node in zookeeper synchronously.
- Zookeeper::get — Gets the data associated with a node synchronously.
- Zookeeper::getAcl — Gets the acl associated with a node synchronously.
- Zookeeper::getClientId — return the client session id, only valid if the connections is currently connected (ie. last watcher state is ZOO_CONNECTED_STATE)
- Zookeeper::getRecvTimeout — Return the timeout for this session, only valid if the connections is currently connected (ie. last watcher state is ZOO_CONNECTED_STATE). This value may change after a server re-connect.
- Zookeeper::getState — Get the state of the zookeeper connection.
- Zookeeper::isRecoverable — Checks if the current zookeeper connection state can be recovered.
- Zookeeper::set — Sets the data associated with a node.
- Zookeeper::setAcl — Sets the acl associated with a node synchronously.
- Zookeeper::setDebugLevel — Sets the debugging level for the library.
- Zookeeper::setDeterministicConnOrder — Enable/disable quorum endpoint order randomization.
- Zookeeper::setLogStream — Sets the stream to be used by the library for logging.
- Zookeeper::setWatcher — Set a watcher function.

The ZooKeeper class

Introduction

Represents ZooKeeper session.

Class synopsis

Zookeeper

class Zookeeper {

/* Methods */

public __construct ([ string $host = '' [, callable $watcher_cb = null [, int $recv_timeout = 10000 ]]] )

public bool addAuth ( string $scheme , string $cert [, callable $completion_cb = null ] )

public void connect ( string $host [, callable $watcher_cb = null [, int $recv_timeout = 10000 ]] )

public string create ( string $path , string $value , array $acls [, int $flags = null ] )

public bool delete ( string $path [, int $version = -1 ] )

public bool exists ( string $path [, callable $watcher_cb = null ] )

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

public array getAcl ( string $path )

public int getClientId ( void )

public int getRecvTimeout ( void )

public int getState ( void )

public bool isRecoverable ( void )

public bool set ( string $path , string $value [, int $version = -1 [, array &$stat = null ]] )

public bool setAcl ( string $path , int $version , array $acl )

public static bool setDebugLevel ( int $logLevel )

public static bool setDeterministicConnOrder ( bool $yesOrNo )

public bool setLogStream ( resource $stream )

public bool setWatcher ( callable $watcher_cb )

/* Constants */

const integer PERM_READ = 1 ;

const integer PERM_WRITE = 2 ;

const integer PERM_CREATE = 4 ;

const integer PERM_DELETE = 8 ;

const integer PERM_ADMIN = 16 ;

const integer PERM_ALL = 31 ;

const integer LOG_LEVEL_ERROR = 1 ;

const integer LOG_LEVEL_WARN = 2 ;

const integer LOG_LEVEL_INFO = 3 ;

const integer LOG_LEVEL_DEBUG = 4 ;

const integer EXPIRED_SESSION_STATE = -112 ;

const integer AUTH_FAILED_STATE = -113 ;

const integer CONNECTING_STATE = 1 ;

const integer ASSOCIATING_STATE = 2 ;

const integer CONNECTED_STATE = 3 ;

const integer READONLY_STATE = 5 ;

const integer NOTCONNECTED_STATE = 999 ;

}

Predefined Constants

ZooKeeper Permissions

Zookeeper::PERM_READ: Can read nodes value and list its children
Zookeeper::PERM_WRITE: Can set the nodes value
Zookeeper::PERM_CREATE: Can create children
Zookeeper::PERM_DELETE: Can delete children
Zookeeper::PERM_ADMIN: Can execute set_acl()
Zookeeper::PERM_ALL: All of the above flags ORd together

ZooKeeper Log Levels

Zookeeper::LOG_LEVEL_ERROR: Outputs only error mesages
Zookeeper::LOG_LEVEL_WARN: Outputs errors/warnings
Zookeeper::LOG_LEVEL_INFO: Outputs big action messages besides errors/warnings
Zookeeper::LOG_LEVEL_DEBUG: Outputs all

ZooKeeper States

Zookeeper::EXPIRED_SESSION_STATE: Connected but session expired
Zookeeper::AUTH_FAILED_STATE: Connected but auth failed
Zookeeper::CONNECTING_STATE: Connecting
Zookeeper::ASSOCIATING_STATE: Associating
Zookeeper::CONNECTED_STATE: Connected
Zookeeper::READONLY_STATE: TODO: help us improve this extension.
Zookeeper::NOTCONNECTED_STATE: Connection failed