get with a watcher could not invoke the watcher callback

[ifeelcold1999]

class Zookeeper_Module {

    private $zookeeper;

    public function __construct(){
        $this->ci = & get_instance();
        $zookeeper_server = $this->ci->config->item('zookeeper_server');

        $this->zookeeper = new Zookeeper($zookeeper_server);
    }

    public function set($path, $value){
        $this->zookeeper->set($path, $value);
    }

    public function get($path, $watch_cb = null){
        return $this->zookeeper->get($path, $watch_cb);
    }

    public function get_watch_cb($event_type = '', $stat = '', $path = ''){
        error_log('hello from get_watcher_cb');
        $value = $this->get($path, array($this, 'get_watch_cb'));
        // update redis cache
        $this->ci->cache->redis->save('some cache key', $value);
    }
}

class MyTest{
    public function get(){
        $zookeeper = new Zookeeper_Module ();

        $value = $zookeeper->get( '/foo/bar', array (
            $zookeeper,
            'get_watch_cb'
        ) );
    }

    public function set(){
        $zookeeper = new Zookeeper_Module ();
        $zookeeper->set( '/foo/bar', 'some value');
    }
}

Running this in php-5.6.14 thread safety disabled, get($path , $watch_cb) and set($path, $value) work fine, but the get_watch_cb function never works.

This is very similar with https://github.com/andreiz/php-zookeeper/issues/34, but my php is thread safety disabled, so it doesn't have much help.

[ifeelcold1999]

I find the key! I didn't add a while(true) in my code, so everything includes the watcher is gone when the request is finished.