dineshsprabu

/* dumping a particular collection */
mongodump --host 127.0.0.1 --port 27017 --out <backup-path> --db '<db-name>' --collection '<collection-name>'

/* dumping the entire DB */
mongodump --host 127.0.0.1 --port 27017 --out <backup-path> --db <db-name>

/* restoring backup/dump */
mongorestore --host 127.0.0.1  --port 27017  <backup-path>

dineshsprabu

/* 
Bring up the selenium webdriver server using below command 
phantomjs --proxy=104.131.57.228:8090 --proxy-type=http  --webdriver=8543 
The value in --webdriver is the port binded on wd server
*/

var webdriver = require('selenium-webdriver');

var browser = webdriver.Capabilities.phantomjs();
browser.set('phantomjs.page.settings.userAgent', "Mozilla");

dineshsprabu

/*
Make sure you have scree on your server using screen --version
if not, install using 'sudo apt-get install screen'.
Make sure you have phantomjs installed and accessible on the path 
'/usr/bin/phantomjs'.
*/

screen -dmS test bash -c '/usr/bin/phantomjs -w ; exec bash'

dineshsprabu

cd ~

/* Below is the direct download link for compiled binary */
wget https://github.com/Pyppe/phantomjs2.0-ubuntu14.04x64/raw/master/bin/phantomjs

/* Making PhantomJS accessible */
mv ~/phantomjs /usr/local/share/phantomjs
ln -s /usr/local/share/phantomjs /usr/local/bin/phantomjs
ln -s /usr/local/share/phantomjs /usr/bin/phantomjs

dineshsprabu

/* 
Make sure you install phantomjs 2.0 which is really stable
Follow the below link for instructions to install it,
https://gist.github.com/dineshsprabu/543de6b41a7597967ea7
*/

>> vi /usr/bin/runphantom.sh

#!/bin/bash
bash -c '/usr/bin/phantomjs -w ; exec bash' &

dineshsprabu

var net = require('net');
var Promise = require('bluebird');

function checkConnection(host, port, timeout) {
    return new Promise(function(resolve, reject) {
        timeout = timeout || 10000;     // default of 10 seconds
        var timer = setTimeout(function() {
            reject("timeout");
            socket.end();
        }, timeout);

dineshsprabu

/* npm install events */
var EventEmitter = require('events').EventEmitter;

/* creating an event emitter object */
var eventObj = new EventEmitter();

/* making it to listen for the event (catchme) with resulting action (console.log) */
eventObj.on('catchme', function(){
	console.log(" You Catched Me! ");
});

dineshsprabu

/* Best way to check whether a variable is string or not */
function isString(o) {
    return typeof o == "string" || (typeof o == "object" && o.constructor === String);
}

dineshsprabu

/* mongodb version 3.2 */

mongod --storageEngine wiredTiger --dbpath="./data/"

/* Migrate data from mmapv1 by taking a dump of data from db using mmapv1 and restore on wiredTiger */
/* Ref: https://gist.github.com/dineshsprabu/06f2ede79753ff4f43f5 */

dineshsprabu

var crawler = function(initialIPPool){

	//private variable
	var privateVariable = 10;

	//instance variable;
	this.pool = initialIPPool;

	//private function
	var privateCrawler = function(privatePool){