The Zookeeper class

(PECL zookeeper >= 0.1.0)

Introduction

Represents ZooKeeper session.

Class synopsis

classZookeeper {

public__construct(string$host = '', callable$watcher_cb = null, int$recv_timeout = 10000)

publicaddAuth(string$scheme, string$cert, callable$completion_cb = null): bool

publicclose(): void

publicconnect(string$host, callable$watcher_cb = null, int$recv_timeout = 10000): void

publiccreate(
    string$path,
    string$value,
    array$acls,
    int$flags = null
): string

publicdelete(string$path, int$version = -1): bool

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

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

publicgetAcl(string$path): array

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

publicgetClientId(): int

publicgetConfig(): ZookeeperConfig

publicgetRecvTimeout(): int

publicgetState(): int

publicisRecoverable(): bool

publicset(
    string$path,
    string$value,
    int$version = -1,
    array&$stat = null
): bool

publicsetAcl(string$path, int$version, array$acl): bool

publicstaticsetDebugLevel(int$logLevel): bool

publicstaticsetDeterministicConnOrder(bool$yesOrNo): bool

publicsetLogStream(resource$stream): bool

publicsetWatcher(callable$watcher_cb): bool

constintPERM_READ = 1;

constintPERM_WRITE = 2;

constintPERM_CREATE = 4;

constintPERM_DELETE = 8;

constintPERM_ADMIN = 16;

constintPERM_ALL = 31;

constintEPHEMERAL = 1;

constintSEQUENCE = 2;

constintLOG_LEVEL_ERROR = 1;

constintLOG_LEVEL_WARN = 2;

constintLOG_LEVEL_INFO = 3;

constintLOG_LEVEL_DEBUG = 4;

constintEXPIRED_SESSION_STATE = -112;

constintAUTH_FAILED_STATE = -113;

constintCONNECTING_STATE = 1;

constintASSOCIATING_STATE = 2;

constintCONNECTED_STATE = 3;

constintREADONLY_STATE = 5;

constintNOTCONNECTED_STATE = 999;

constintCREATED_EVENT = 1;

constintDELETED_EVENT = 2;

constintCHANGED_EVENT = 3;

constintCHILD_EVENT = 4;

constintSESSION_EVENT = -1;

constintNOTWATCHING_EVENT = -2;

constintSYSTEMERROR = -1;

constintRUNTIMEINCONSISTENCY = -2;

constintDATAINCONSISTENCY = -3;

constintCONNECTIONLOSS = -4;

constintMARSHALLINGERROR = -5;

constintUNIMPLEMENTED = -6;

constintOPERATIONTIMEOUT = -7;

constintBADARGUMENTS = -8;

constintINVALIDSTATE = -9;

constintNEWCONFIGNOQUORUM = -13;

constintRECONFIGINPROGRESS = -14;

constintOK = 0;

constintAPIERROR = -100;

constintNONODE = -101;

constintNOAUTH = -102;

constintBADVERSION = -103;

constintNOCHILDRENFOREPHEMERALS = -108;

constintNODEEXISTS = -110;

constintNOTEMPTY = -111;

constintSESSIONEXPIRED = -112;

constintINVALIDCALLBACK = -113;

constintINVALIDACL = -114;

constintAUTHFAILED = -115;

constintCLOSING = -116;

constintNOTHING = -117;

constintSESSIONMOVED = -118;

constintNOTREADONLY = -119;

constintEPHEMERALONLOCALSESSION = -120;

constintNOWATCHER = -121;

constintRECONFIGDISABLED = -122;

}

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 Create Flags

Zookeeper::EPHEMERAL: If Zookeeper::EPHEMERAL flag is set, the node will automatically get removed if the client session goes away.
Zookeeper::SEQUENCE: If the Zookeeper::SEQUENCE flag is set, a unique monotonically increasing sequence number is appended to the path name. The sequence number is always fixed length of 10 digits, 0 padded.

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

ZooKeeper Watch Types

Zookeeper::CREATED_EVENT

A node has been created

This is only generated by watches on non-existent nodes. These watches are set using Zookeeper::exists.

Zookeeper::DELETED_EVENT

A node has been deleted

This is only generated by watches on nodes. These watches are set using Zookeeper::exists and Zookeeper::get.

Zookeeper::CHANGED_EVENT

A node has changed

This is only generated by watches on nodes. These watches are set using Zookeeper::exists and Zookeeper::get.

Zookeeper::CHILD_EVENT

A change as occurred in the list of children

This is only generated by watches on the child list of a node. These watches are set using Zookeeper::getChildren.

Zookeeper::SESSION_EVENT

A session has been lost

This is generated when a client loses contact or reconnects with a server.

Zookeeper::NOTWATCHING_EVENT

A watch has been removed

This is generated when the server for some reason, probably a resource constraint, will no longer watch a node for a client.

ZooKeeper System and Server-side Errors

Zookeeper::SYSTEMERROR

This is never thrown by the server, it shouldn't be used other than to indicate a range. Specifically error codes greater than this value, but lesser than Zookeeper::APIERROR, are system errors.

Zookeeper::RUNTIMEINCONSISTENCY

A runtime inconsistency was found.

Zookeeper::DATAINCONSISTENCY

A data inconsistency was found.

Zookeeper::CONNECTIONLOSS

Connection to the server has been lost.

Zookeeper::MARSHALLINGERROR

Error while marshalling or unmarshalling data.

Zookeeper::UNIMPLEMENTED

Operation is unimplemented.

Zookeeper::OPERATIONTIMEOUT

Operation timeout.

Zookeeper::BADARGUMENTS

Invalid arguments.

Zookeeper::INVALIDSTATE

Invliad zhandle state.

Zookeeper::NEWCONFIGNOQUORUM

No quorum of new config is connected and up-to-date with the leader of last committed config - try invoking reconfiguration after new servers are connected and synced.

Available as of ZooKeeper 3.5.0

Zookeeper::RECONFIGINPROGRESS

Reconfiguration requested while another reconfiguration is currently in progress. This is currently not supported. Please retry.