d3v4modules

<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <script src="https://d3js.org/d3.v4.min.js"></script>
  <style>
    .node circle {
      fill: #999;
    }

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

.node--internal circle {
      fill: #555;
    }

.node--internal text {
      text-shadow: 0 1px 0 #fff, 0 -1px 0 #fff, 1px 0 0 #fff, -1px 0 0 #fff;
    }

.link {
      fill: none;
      stroke: #555;
      stroke-opacity: 0.4;
      stroke-width: 1.5px;
    }
  </style>
</head>

var node = g.selectAll(".node")
       .data(root.descendants())
       .enter().append("g")
       .attr("class", function(d) { return "node" + (d.children ? " node--internal" : " node--leaf"); })
       .attr("transform", function(d) { return "translate(" + d.y + "," + d.x + ")"; })

node.append("circle")
         .attr("r", 2.5);

node.append("text")
          .attr("dy", 3)
          .attr("x", function(d) { return d.children ? -8 : 8; })
          .style("text-anchor", function(d) { return d.children ? "end" : "start"; })
          .text(function(d) { return d.data.name });

});
  </script>
</body>

https://d3js.org/d3.v4.min.js