Javascript tips and tricks

You can access a HTML element id by

Type the id name directly in broswer console eg, my div id = makeCall
makeCall
Suppose if id with '_' , like make_Call it won't work

Use getElement, Works in all case
document.getElementById('makeCall')

or Query selector, it doesn't like id with numbers at start :P
document.querySelector('#makeCall')










If you want to use script or a function in HTML form action you can use 'javascript:myFunction();'



action="javascript:myFunction();

Javascript access functions and variables inside Jquery

(function($) {

$.fn.mainFunction = new function (){

var testVal = "Test";

this.test = function(){

console.log('inside test');

}

}

}(jQuery));

Now you can access testVal and mainFunction.test()

Moniter/Listen/Load test http request Linux

There is a simple tool tcpflow to capture the actual headers coming to your host

tcpflow port 80

To be more specific use.

tcpflow -p -c -i eth0 port 80 | grep -oE '(GET|POST|HEAD) .* HTTP/1.[01]|Host: .*'

Capture only number of hits: 

tcpflow -p -c -i eth0 port 80 | grep 'Date'

Use ab tool (apache2-tools) to benchmark the load on apache or any other http server like pyhton,node etc

ab -n 1000 -c 10 http:ipaddresss:port/                    / is important after port number 

-n number of request to send

-c total request to send per sec / concurrent req

You can use rate limit to allow number of connection per sec/min/hr with --limit module in IPTABLES

Iptables -A INPUT -p tcp --dport 80 -m state --state NEW -m limit --limit 10/second --limit-burst 10 -j ACCEPT