nodekeeper.cc

NodeKeeper problem

#include <v8.h>
#include <node.h>
#include <node_events.h>
#include <c-client-src/zookeeper.h>

#include <iostream>

using namespace node;
using namespace v8;

class NodeKeeper : public EventEmitter
{ 
private:
  ev_async * completed_;
  
public:
  static void Init(Handle<Object> target)
  {
    HandleScope scope;
    Local<FunctionTemplate> t = FunctionTemplate::New(New);
    t->Inherit(EventEmitter::constructor_template);
    t->InstanceTemplate()->SetInternalFieldCount(1);
    NODE_SET_PROTOTYPE_METHOD(t, "trigger", trigger);
    target->Set(String::NewSymbol("NodeKeeper"), t->GetFunction());
  }
  
  static void Complete(EV_P_ ev_async * w, int revents)
  {
    NodeKeeper * hw = static_cast<NodeKeeper *>(w->data);
    hw->Emit(String::New("ping"), 0, NULL);
  }
  
  NodeKeeper()
  {
    completed_ = new ev_async();
  }
  
  ~NodeKeeper()
  {
    ev_async_stop(EV_DEFAULT_UC_ completed_);
    delete completed_;
  }

private:
  static Handle<Value> New(const Arguments& args)
  {
    HandleScope scope;
    NodeKeeper * hw = new NodeKeeper();
    hw->completed_->data = hw;
  	ev_async_init(hw->completed_, NodeKeeper::Complete);
  	ev_async_start(EV_DEFAULT_UC_ hw->completed_);
  	ev_unref(EV_DEFAULT_UC);
  	hw->Wrap(args.This());
    return args.This();
  }

  static Handle<Value> trigger(const Arguments & args)
  {
    HandleScope scope;
    NodeKeeper * hw = ObjectWrap::Unwrap<NodeKeeper>(args.This());
    if (args.Length() < 2 || !args[0]->IsString() || !args[1]->IsInt32()) {
      return ThrowException(Exception::Error(String::New("Must give a connection string (host:port) and a timeout (integer) to initialize ZooKeeper")));
    }
    
    String::AsciiValue connectionString(args[0]->ToString());
    zookeeper_init(* connectionString, watcherCallback, args[1]->ToInt32()->Value(), 0, hw, 0);
    return Undefined();
  }
  
  static void watcherCallback(zhandle_t * zh, int type, int state, const char * path, void * watcherCtx)
  {
    HandleScope scope;
    NodeKeeper * that = (NodeKeeper *)watcherCtx;
    ev_async_send(EV_DEFAULT_UC_ that->completed_);
    ev_ref(EV_DEFAULT_UC);
  }
};

extern "C" {
  static void init(Handle<Object> target)
  {
    HandleScope scope;
    NodeKeeper::Init(target);
  }
  NODE_MODULE(nodekeeper, init);
}

test.js

var hello = require('./build/default/nodekeeper');

var hi = new hello.NodeKeeper();
hi.addListener('ping', function () {
  console.log('pong');
});
hi.trigger('localhost:2181', 5000);

var http = require('http');
http.createServer(function (req, res) {
  res.writeHead(200, {'Content-Type': 'text/plain'});
  res.end('Hello World\n');
}).listen(8124, "127.0.0.1");
console.log('Server running at http://127.0.0.1:8124/');