JSFiddle - React, Tailwind, and code Playground

HTML

<div id="data">

</div>

JavaScript

var jsonSource='{"error_code":0, "ext_info":{"name":{"firstName":"John","lastName":"Jonson","nickName":"JJ"}}}';
 var obj=JSON.parse(jsonSource);

 function showJson(obj){
 		var returnValue='';
     for(var key in obj){
        if(typeof obj[key]==='object'){
            returnValue+='<div>'+key+'/\n';
            returnValue+=showJson(obj[key]);
            returnValue+='</div>';
         } else{
            returnValue+=key+'equal'+obj[key]; 
         }  
     }
     return returnValue;
 }

document.getElementById('data').innerHTML= showJson(obj);