get to know when the ajax calls are made and done

[singamcet]

how to know when ajax calls are made and done .....then how to check the page is fully loaded or not
am new to nightmare js
my code is here

var Nightmare = require('nightmare');
require('nightmare-webrequest-addon');

var name = "vineeth";
var cancel = false;

var nightmare = Nightmare({
show: true,
switches: {
'proxy-server': 'localhost:3128' , // set the proxy server here ...
'ignore-certificate-errors' : true
},

});

nightmare.on('onBeforeRequest', function(details, callback){
if(details && details.hasOwnProperty("resourceType")){
console.log(details.resourceType)
}
//callback(details);
})

nightmare.onBeforeRequest([ "*.css" ],function(details, callback){
if(details && details.hasOwnProperty("resourceType") && details.resourceType == "image"){
callback({ cancel : true } )
}
else{
callback({ cancel : false } )
}
})

nightmare
.goto('https://www.flipkart.com/zesture-cotton-floral-double-bedsheet/p/itmepqvqyyzznfsn?pid=BDSEPQVQCGMQRY7Y&srno=b_1_2&otracker=hp_reco_Discounts%20for%20You_2_Min%2050%25%20off_vdm%2Fuj4%2F64i_1&lid=LSTBDSEPQVQCGMQRY7YJBFIYW&fm=personalisedRecommendation/discount&iid=513dcd7a-61cb-4633-845f-bff06e73fddd.BDSEPQVQCGMQRY7Y.SEARCH')
// .wait(10000)
.end()
.then(function(ip) { // This will log the Proxy's IP
console.log('proxy IP:', ip);
});