index.html

<!doctype html>
<html>
<head>
  <title>Network | Basic usage</title>

  <script type="text/javascript" src="https://visjs.github.io/vis-network/dist/vis-network.min.js"></script>
  <link href="https://visjs.github.io/vis-network/dist/vis-network.min.css" rel="stylesheet" type="text/css" />

  <style type="text/css">
    #mynetwork {
      width: 1600px;
      height: 1200px;
      border: 1px solid lightgray;
    }
  </style>
</head>
<body>

<div id="mynetwork"></div>

<script type="text/javascript" src="nodes.json"></script>
<script type="text/javascript">

//url = "http://192.168.0.178:8081/nodes.json"
//data = obj = await (await fetch(url)).json();

var parsed = JSON.parse(data);
    // create a network
    var container = document.getElementById("mynetwork");

    // provide the data in the vis format
    var data = {
      nodes: parsed.nodes,
      edges: parsed.links
    };
    var options = {
                layout: {
                    randomSeed: 6,
                    hierarchical: {
                        direction: "LR",
                        sortMethod: "directed",
                        levelSeparation: 200,
                        nodeSpacing: 40,

                    }
                },
                interaction: {
                    hover: true
                }
   };

    // initialize your network!
    var network = new vis.Network(container, data, options);
</script>


</html>