Tag: node.js

Setting up a Node.js Cluster

 

var cluster = require('cluster');
var numCPUs = require('os').cpus().length;

if (cluster.isMaster) {
  // Fork workers.
  for (var i = 0; i < numCPUs; i++) {
    cluster.fork();
  }

   Object.keys(cluster.workers).forEach(function(id) {
    console.log("I am running with ID : "+cluster.workers[id].process.pid);
  });

  cluster.on('exit', function(worker, code, signal) {
    console.log('worker ' + worker.process.pid + ' died');
  });
} else {

      //Do further processing.
}

Express :

app.js

var express=require("express");
var app=express();

app.get('/',function(req,res){

          res.end("Hello world !");

});

app.listen(3000,function(){

          console.log("Running at PORT 3000");

});

cluster.js

var cluster = require('cluster');
var numCPUs = require('os').cpus().length;

if (cluster.isMaster) {

  for (var i = 0; i < numCPUs; i++) {
    cluster.fork();
  }

  cluster.on('exit', function(worker, code, signal) {
    console.log('worker ' + worker.process.pid + ' died');
  });
} else {

    //change this line to Your Node.js app entry point.
    require("./app.js");
}

References
https://codequs.com/p/BkCZ1VMY/setting-up-a-node-js-cluster/
https://www.sitepoint.com/how-to-create-a-node-js-cluster-for-speeding-up-your-apps/
https://nodejs.org/api/cluster.html

Use ExpressJS to Get URL and POST Parameters

GET

// grab the packages we need
var express = require('express');
var app = express();
var port = process.env.PORT || 8080;

// routes will go here

// start the server
app.listen(port);
console.log('Server started! At http://localhost:' + port);
http://example.com/api/users?id=4&token=sdfa3&geo=us
// routes will go here
app.get('/api/users', function(req, res) {
  var user_id = req.param('id');
  var token = req.param('token');
  var geo = req.param('geo');  

  res.send(user_id + ' ' + token + ' ' + geo);
});

POST

npm install body-parser --save
var bodyParser = require('body-parser');
app.use(bodyParser.json()); // support json encoded bodies
app.use(bodyParser.urlencoded({ extended: true })); // support encoded bodies

// POST http://localhost:8080/api/users
// parameters sent with 
app.post('/api/users', function(req, res) {
    var user_id = req.body.id;
    var token = req.body.token;
    var geo = req.body.geo;

    res.send(user_id + ' ' + token + ' ' + geo);
});

References
https://scotch.io/tutorials/use-expressjs-to-get-url-and-post-parameters
http://www.tutorialspoint.com/nodejs/nodejs_express_framework.htm
https://www.npmjs.com/package/body-parser-json