php 连接zookeeper实例1、安装成功zookeeper后,在zookeeper 的bin目录下有启动相应的启动脚本启动Server ./zkServer.sh start 启动client:(*注:cli需要安装java) zkCli.sh2、PHP实例:class ZookeeperDemo extends Zookeeper { public function watcher( $i, $type, $key ) { echo "Insider Watcher\n" ; // Watcher gets consumed so we need to set a new one $this->get( '/test', array ($this, 'watcher' ) ); }}$zoo = new ZookeeperDemo( '127.0.0.1:2181' );$zoo->get( '/test', array ($zoo, 'watcher' ) );while ( true ) { echo '.' ; sleep(2);}leader与worker任务的分配:class Worker extends Zookeeper { const CONTAINER = '/cluster' ; protected $acl = array( array ( 'perms' => Zookeeper:: PERM_ALL, 'scheme' => 'world' , 'id' => 'anyone' ) ); private $isLeader = false; private $znode ; public function __construct( $host = '', $watcher_cb = null , $recv_timeout = 10000 ) { parent:: __construct( $host, $watcher_cb, $recv_timeout ); } public function register() { if( ! $this->exists( self ::CONTAINER ) ) { $this->create( self ::CONTAINER , null, $this-> acl ); } $this->znode = $this->create( self ::CONTAINER . '/w-' , null , $this->acl, Zookeeper::EPHEMERAL | Zookeeper::SEQUENCE ); $this-> znode = str_replace( self ::CONTAINER .'/' , '' , $this-> znode ); printf( "I'm registred as: %s\n", $this-> znode ); $watching = $this->watchPrevious(); if( $watching == $this-> znode ) { printf( "Nobody here, I'm the leader\n" ); $this->setLeader( true ); } else { printf( "I'm watching %s\n" , $watching ); } } public function watchPrevious() { $workers = $this->getChildren( self ::CONTAINER ); sort( $workers ); $size = sizeof( $workers ); for( $i = 0 ; $i if( $this-> znode == $workers[ $i ] ) { if ( $i > 0 ) { $this->get( self ::CONTAINER . '/' . $workers[ $i - 1 ], array ( $this, 'watchNode' ) ); return $workers[ $i - 1 ]; } return $workers[ $i ]; } } throw new Exception( sprintf( "Something went very wrong! I can't find myself: %s/%s", self ::CONTAINER , $this-> znode ) ); } public function watchNode( $i, $type, $name ) { $watching = $this->watchPrevious(); if( $watching == $this-> znode ) { printf( "I'm the new leader!\n" ); $this->setLeader( true ); } else { printf( "Now I'm watching %s\n" , $watching ); } } public function isLeader() { return $this-> isLeader ; } public function setLeader($flag) { $this-> isLeader = $flag; } public function run() { $this->register(); while( true ) { if( $this->isLeader() ) { $this->doLeaderJob(); } else { $this->doWorkerJob(); } sleep( 2 ); } } public function doLeaderJob() { echo "Leading\n" ; } public function doWorkerJob() { echo "Working\n" ; }}$worker = new Worker( '127.0.0.1:2181' );$worker->run();可以启动3个php进程,查看脚本的运行。进程1:[[email protected] zookeeper]# php -f worker.php I'm registred as: w-0000000010Nobody here, I'm the leaderLeading进程2:[[email protected] zookeeper]$ php -f worker.php I'm registred as: w-0000000011I'm watching w-0000000010Working进程3:[[email protected] zookeeper]$ php -f worker.php I'm registred as: w-0000000012I'm watching w-0000000011Workingctrl + c 关闭leader进程后,会发现进程2与3会选举出新的leader 09-19 04:10