JSFiddle - React, Tailwind, and code Playground

HTML

<div id="area1"></div>
<div id="area2"></div>

CSS

.bs-sidebar .nav > .active > ul {
		display: block;
		margin-bottom: 8px;
	}
	text.shadow {
		stroke: white;
		stroke-width: 2.3px;
		opacity: 0.5;
	}
	
	.node {
		cursor: pointer;
	}

	.node circle {
	  fill: #fff;
	  stroke: steelblue;
	  stroke-width: 1.5px;
	}

	.node text {
	  font: 10px sans-serif;
	}

	.link {
	  fill: none;
	  stroke: #ccc;
	  stroke-width: 1.5px;
	}

JavaScript

var data = [
	 { "name" : "ABC", "parent":"DEF", "relation": "ghi", "depth": 1 },
	 { "name" : "DEF", "parent":"null", "relation": "null", "depth": 0 },
	 { "name" : "new_name", "parent":"ABC", "relation": "rel", "depth": 2 },
	 { "name" : "new_name2", "parent":"ABC", "relation": "foo", "depth": 2 },
	 { "name" : "Foo", "parent":"DEF", "relation": "rel", "depth": 2 }
	];

// *********** Convert flat data into a nice tree ***************
// create a name: node map
var dataMap = data.reduce(function(map, node) {
	map[node.name] = node;
	return map;
}, {});

// create the tree array
var treeData = [];
data.forEach(function(node) {
	// add to parent
	var parent = dataMap[node.parent];
	if (parent) {
		// create child array if it doesn't exist
		(parent.children || (parent.children = []))
			// add node to child array
			.push(node);
	} else {
		// parent is null or missing
		treeData.push(node);
	}
});

// show what we've got
d3.select('#area1').append('pre')
    .text(JSON.stringify(treeData, null, '  '));

// ************** Generate the tree diagram	 *****************
var margin = {top: 20, right: 120, bottom: 20, left: 120},
	width = 960 - margin.right - margin.left,
	height = 500 - margin.top - margin.bottom;
	
var i = 0,
	duration = 750,
	root;

var tree = d3.layout.tree()
	.size([height, width]);

var diagonal = d3.svg.diagonal()
	.projection(function(d) { return [d.y, d.x]; });

var svg = d3.select("#area2").append("svg")
	.attr("width", width + margin.right + margin.left)
	.attr("height", height + margin.top + margin.bottom)
  .append("g")
	.attr("transform", "translate(" + margin.left + "," + margin.top + ")");

//d3.json("data/example.json", function(error, DEF) {
  root = treeData;
  root.x0 = height / 2;
  root.y0 = 0;

  function collapse(d) {
	if (d.children) {
	  d._children = d.children;
	  d._children.forEach(collapse);
	  d.children = null;
	}
  }
  
  root.children.forEach(collapse);
 ...