After nodejs get requests a url, how can it obtain json data returned by the url, which is extremely urgent?

  node.js, question

After nodejs get requests a url, how can it obtain json data returned by the url, which is extremely urgent?

Like this,

http.get('http://abc.com/api"', function (res) {
 //console.log("statusCode: ", res.statusCode);
 //console.log("headers: ", res.headers);
 var json = '';
 res.on('data', function (d) {
 Json plus = d;
 });
 res.on('end',function(){
 //Data Acquired
 json = JSON.parse(json);
 });
 }).on('error', function (e) {
 console.error(e);
 });