Add live realtime data | UNL Map JS Docs

Use realtime GeoJSON data streams to move a symbol on your map.

Note

If you want to test this example, edit it in JSFiddle or CodePen and replace the "YOUR-OWN-API-KEY" and "YOUR-OWN-VPM-ID" placeholders with your actual api key and vpm id.

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>Add live realtime data</title>
<meta name="viewport" content="initial-scale=1,maximum-scale=1,user-scalable=no" />
<script src="https://unpkg.com/unl-map-js@0.1.5/lib/unl-map-js.js"></script>
<link href="https://unpkg.com/unl-map-js@0.1.5/lib/unl-map-js.css" rel="stylesheet" />
<link
href="https://unpkg.com/maplibre-gl@2.1.9/dist/maplibre-gl.css"
rel="stylesheet"
/>
<style>
	body { margin: 0; padding: 0; }
	#map { position: absolute; top: 0; bottom: 0; width: 100%; }
</style>
</head>
<body>
<div id="map"></div>
 
<script>
var map = new UnlSdk.Map({
container: "map",
apiKey: "YOUR-OWN-API-KEY",
vpmId: "YOUR-OWN-VPM-ID",
zoom: 0,
});
 
var url = "https://wanderdrone.appspot.com/";
map.on("load", function () {
var request = new XMLHttpRequest();
window.setInterval(function () {
// make a GET request to parse the GeoJSON at the url
request.open("GET", url, true);
request.onload = function () {
if (this.status >= 200 && this.status < 400) {
// retrieve the JSON from the response
var json = JSON.parse(this.response);
 
// update the drone symbol's location on the map
map.getSource("drone").setData(json);
 
// fly the map to the drone's current location
map.flyTo({
center: json.geometry.coordinates,
speed: 0.5,
});
}
};
request.send();
}, 2000);
 
map.addSource("drone", { type: "geojson", data: url });
map.addLayer({
id: "drone",
type: "symbol",
source: "drone",
layout: {
"icon-image": "rocket_15",
},
});
});
</script>
 
</body>
</html>