worker example

worker-example.js

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

var master_event = ['fork', 'online', 'listening', 'disconnect', 'exit', 'setup', 'message'];

if (cluster.isMaster) { 
    master_event.forEach(function(key) {
        switch(key) {
        case 'setup':
            cluster.on(
                key,
                function(envish) {
                    console.log('on' + key + ': ' + JSON.stringify(envish));
                }
            );
            break;

        case 'fork':
        case 'online':
        case 'disconnect':
            cluster.on(
                key,
                function(worker) {
                    console.log('on' + key + ': ' + worker.process.pid);
                }
            );
            break;

        case 'exit':
            cluster.on(
                key,
                function(worker, something, signal) {
                    console.log('on' + key + ': ' + worker.process.pid +  ' terminated by ' + signal);
                }
            );
            break;

        case 'message':
            cluster.on(
                key,
                function(msg, something) {
                    console.log('recieved "' + msg + '"');
                }
            );
            break;

        default:
            // listening
            cluster.on(
                key,
                function() {
                    console.log('on' + key + ': ');
                    console.log(arguments);
                }
            );
            break;
        }

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

    Object.keys(cluster.workers).forEach(function(id) {
        var time = Math.floor( Math.random() * 1000 ) + 300;
        setTimeout(
            function () {
                cluster.workers[id].send('from Master in ' + time);
            },
            time
        );
    });
}
else {
    // worker
    var worker_event = ['online', 'listening', 'disconnect', 'exit', 'error', 'message'];

    console.log("I am running with ID : " + process.pid );

    worker_event.forEach(function (key) {
        switch(key) {
        case 'online':
        case 'disconnect':
            process.on(
                key,
                function() {
                    console.log('  WORKER: on' + key + ': ' + this.process.pid);
                }
            );
            break;

        case 'exit':
            process.on(
                key,
                function(something, signal) {
                    console.log('  WORKER ' + key + ' by ' + signal);
                }
            );
            break;

        case 'message':
            process.on(
                key,
                function(msg, something) {
                    console.log('  WORKER received "' + msg + '"');
                }
            );
            break;

        default:
            // listening, error
            process.on(
                key,
                function() {
                    console.log('  WORKER: on' + key + ': ');
                    console.log(arguments);
                }
            );
            break;
        }

    });

    var time = Math.floor(Math.random() * 1000);
    setTimeout(
        function() {
            process.send('from worker (' + process.pid + ') messaging in ' + time);
        },
        time
    );

    // var time = Math.floor(Math.random() * 1000);
    // setTimeout(
    //     function() {
    //         var msg = 'gooo: ' + time;
    //         console.log(msg);
    //         process.send(msg);
    //     },
    //     time
    // );
}