hersserver/mynow.js

A 'now'-alike server extension not using socket.io

var responding = require('./responding');
var url=require('url');
var EventEmitter = require('events').EventEmitter;
var randomBytes = require('crypto').randomBytes;
function logMyNow(){
  return;
  console.log.apply(console,arguments);
};
function cookieObject(cs){
  var ret = {};
  var rhc = cs.split(';');
  if(rhc){
    var rhcl=rhc.length;
    for(var i=0; i<rhcl; i++){
      var rhce = rhc[i];
      while(rhce[0]===' '){rhce=rhce.substring(1);}
      var ie = rhce.indexOf('=');
      if(ie){
        ret[rhce.substring(0,ie)]=rhce.substring(ie+1);
      }
    }
  }
  return ret;
};
function NowClient(id,cookie,response,diedcb){
  this.clientId=id;
  var t = this;
  var oa = response.connection.remoteAddress;
  var op = response.connection.remotePort;
  this.diedcb = function(){logMyNow(id,oa,':',op,'is dead now');diedcb(t);};
  this.remoteAddress = oa;
  this.remotePort = op;
  this.cookie=cookie;
  this.invoke('setClientId',{clientId:this.clientId},response);
}
NowClient.prototype.setTimeout = function(){
	this.clearTimeout();
	logMyNow(this.clientId,'setting Timeout');
	this.timeout = setTimeout(this.diedcb,15000);
};
NowClient.prototype.clearTimeout = function(){
  if(this.timeout){
    logMyNow(this.clientId,'clearing Timeout');
    clearTimeout(this.timeout);
    delete this.timeout;
  }
};
NowClient.prototype.invoke = function(method,paramobj,response){
  var io = {method:method,paramobj:paramobj};
  //logMyNow('should invoke',method,paramobj);
  if(this.response){
    //logMyNow('invoking',method,'with',io);
    this.sendInvoke(this.response,[io]);
    delete this.response;
    if(response){
      response.end();
    }
    return;
  };
  if(response){
    this.sendInvoke(response,[io]);
    return;
  }
  if(!this.queue){
    this.queue=[];
  }
  this.queue.push(io);
};
NowClient.prototype.hitMe = function(response){
  if(this.response){
    this.response.end();
    delete this.response;
  }
  this.clearTimeout();
  var q = this.queue;
  if(!q){
    this.response = response;
    this.remoteAddress = response.connection.remoteAddress;
    this.remotePort = response.connection.remotePort;
    var t = this;
    //this.response.connection.setTimeout(5000);
		setTimeout(function(){t.invoke('',{});},5000);
    this.response.on('close',function(){delete t.response; t.setTimeout();});
    return;
  }
  //logMyNow('dumping queue',this.queue);
  this.sendInvoke(response);
};
NowClient.prototype.sendInvoke = function(response,arry){
  var a = this.queue||[];
  a = a.concat(arry||[]);
  if(!a.length){return;}
  response.write(JSON.stringify({invoke:a}));
  response.end();
  delete this.queue;
  this.setTimeout();
};
function NowGroup(){
  this.clients={};
}
NowGroup.prototype.addUser = function(cid){
  if(!cid){return;}
  this.clients[cid]=1;
};
function Now(){
  this.clients = {};
  this.groups = {};
  this.cnt = 0;
}
Now.prototype = new EventEmitter();
Now.prototype.constructor = Now;
Now.prototype.byteToString = function(b){
  var ret='';
  ret+=(33+(b&0x0f));
  b>>=4;
  ret+=(33+(b&0x0f));
  return ret;
};
Now.prototype.inc = function(){
  this.cnt++;
  if(this.cnt>100000000){
    this.cnt=1;
  }
  var rb = randomBytes(2);
  var rbs = '';
  rbs+=this.byteToString(rb[0]);
  rbs+=this.byteToString(rb[1]);
  return (new Date()).getTime()+'-'+rbs+'-'+this.cnt;
};
Now.prototype.getGroup = function(name){
  var g = this.groups[name];
  if(!g){
    g=new NowGroup();
    this.groups[name]=g;
    g.now = new Now();
  }
  return g;
};
Now.prototype.removeGroup = function(name){
  delete this.groups[name];
};
Now.prototype.initialize = function(){
  return {now:this};
};
Now.prototype.init = function(cid,request,response){
  if(cid){
    var m = this.clients[cid];
    if(m){
      m.hitMe(response);
      return;
    }
    logMyNow(cid,'not found');
  }
  //logMyNow(response.socket.remoteAddress,cid,'not found');
  var c = this.inc();
  var t = this;
  var ck = {};
  if(request.headers.cookie){
    ck = cookieObject(request.headers.cookie);
  }
  var nc = new NowClient(c,ck,response,function(client){
    t.emit('disconnect',client);
    t.remove(client);
  });
  this.clients[c] = nc;
  this.emit('connect',nc);
};
Now.prototype.deinit = function(cid){
  logMyNow('deiniting',cid);
  var c = this.clients[cid];
  if(!c){return;}
  this.emit('disconnect',c);
  this.remove(c);
};
Now.prototype.remove = function(client){
  var cid = client.clientId;
  client.clearTimeout();
  for(var n in client){
    delete client[n];
  }
  for(var n in this.groups){
    delete this.groups[n].clients[cid];
  }
  delete this.clients[cid];
};
Now.prototype.broadcast = function(){
  var args = Array.prototype.slice.call(arguments);
  for(var n in this.clients){
    //logMyNow('invoking on',c,args);
    var c = this.clients[n];
    c.invoke.apply(c,args);
  }
};
Now.prototype.broadcastOnGroup = function(groupname){
  var args = Array.prototype.slice.call(arguments,1);
  var g = this.groups[groupname];
  if(!g){
    logMyNow('group',groupname,'does not exist');
    return;
  }
  var fordel=[];
  logMyNow('group',groupname,'clients',g.clients);
  for(var n in g.clients){
    logMyNow('invoking on',n,'with',args);
    var c = this.clients[n];
    if(!c){
      //logMyNow('missing client for',n);
      fordel.push(n);
    }else{
      c.invoke.apply(c,args);
    }
  }
  var fdl = fordel.length;
  for(var i=0; i<fdl; i++){
    delete g.clients[fordel[i]];
  }
};
Now.prototype.getClient = function(cid,cb){
  if(typeof cb !== 'function'){return;}
  var c = this.clients[cid];
  cb.apply(c,[c]);//provide the client as 'this' or as the first and only param
};
var _NowInstance = new Now();
responding.createResponder({
  name:'now/init',
  handler:function(cid){
    _NowInstance.init(cid,this.request,this.response);
  },
  params:['clientId'],
  parent:_NowInstance
});
responding.createResponder({
  name:'now/deinit',
  handler:function(cid){
    _NowInstance.deinit(cid,this.request,this.response);
  },
  params:['clientId'],
  parent:_NowInstance
});
module.exports = _NowInstance;