<!DOCTYPE html>
<html>
<head>
  <script type="text/javascript">
    // Demonstrates how the navigator.mediaDevices api can be used
    // for querying media capture devices.
    const mediaDevices = navigator.mediaDevices;

    function intervalCallback() {
      mediaDevices.enumerateDevices()
        .then((sequenceMediaDevices) => {
          let strValue = "\nFound " + sequenceMediaDevices.length
                         + " media devices: \n";
          let i = 0;
          for (let device of sequenceMediaDevices) {
            strValue += "  device[" + i + "].kind: "  + device.kind  + "\n";
            strValue += "  device[" + i + "].label: " + device.label + "\n";
            i++;
          }
          console.log(strValue);
        })
        .catch((msg) => console.log(
            "Exception happened while enumerating devices, reason: " + msg));
    }

    window.setInterval(intervalCallback, 500);
  </script>
</head>

<body>
</body>
</html>