nightmare

scraper.js

var Nightmare = require('nightmare');
var nightmare = Nightmare({ show: false })

nightmare
  // .useragent('Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:41.0) Gecko/20100101 Firefox/41.0')
  .goto('https://www.practo.com/bangalore/doctor/dr-shankar-kumar-diabetologist-1/')
  .wait(5000)
  .click("#reviewsNavLink")
  .wait(5000)
  .evaluate(function(){
  	var a = document.getElementById('reviewsTab');
  	var i = setInterval(function(){
	  	var x = a.getElementsByClassName('btn btn-white next-page recommended-next-page');
	  	if(x == undefined || x.length == 0){
	  		clearInterval(i);
	  	}
	  	else{
	  		x[0].click();
	  	}
  	}, 5000);
  })
  .wait(5000000)
  .then(function (result) {
    console.log(result)
  })

nightmare.end()