biketrack-plainjs/map.js

var map = L.map('map').setView([49.41607523, 8.672200499], 19);  
L.tileLayer('https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
    maxZoom: 44,
    attribution: '© OpenStreetMap'
}).addTo(map);

// helper function for displayRoute()
async function prepare(){
   var allcoordinates = getAllCoordinates('coordinates');
   return allcoordinates;
}

async function displayRoute() {
var allcoordinates = await prepare();
console.log(allcoordinates);
//var marker = L.marker([49.41607523,8.67220049]).addTo(map);
var polyline = L.polyline(allcoordinates, {color: 'red'}).addTo(map);

var currentime = await getCurrentTime()
var ul = document.getElementById("list");
var li = document.createElement("li");
li.appendChild(document.createTextNode("Last travelled route on: "   +currentime+""));
  ul.appendChild(li);
  map.fitBounds(polyline.getBounds());
map.fitBounds(polyline.getBounds())
return currentime
}

async function showBike(){
  var current_cord = await getCurrentCoordinate() 
    L.tileLayer('http://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png').addTo(map);
    L.marker(current_cord).addTo(map)
    .bindPopup(' Your BIKE!')
    .openPopup();
}