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html - How To Display Multiple Markers Coordinates Stored In Firebase Database On Google Maps

I am trying to get the coordinates that are saved in the firebase real-time database and display them on a map using the google maps API. This is the code I have so far. Right now it opens and shows the users current location using the html5 geolocation API and it syncs the lat and long coordinates to the firebase real-time database using Geofire.

enter image description here

I don't know how to retrieve these points and have multiple points on the google map at the same time showing different users locations. If anyone could help me with this I would really appreciate it.

<script src="https://cdn.firebase.com/libs/geofire/4.1.2/geofire.min.js"></script>
<script src="https://www.gstatic.com/firebasejs/4.12.1/firebase.js"></script>
<!DOCTYPE html>
<html>
  <head>
    <title>Geolocation</title>
    <meta name="viewport" content="initial-scale=1.0, user-scalable=no">
    <meta charset="utf-8">
    <style>
      /* Always set the map height explicitly to define the size of the div
       * element that contains the map. */
      #map {
        height: 100%;
      }
      /* Optional: Makes the sample page fill the window. */
      html, body {
        height: 100%;
        margin: 0;
        padding: 0;
      }
    </style>
    <!-- Place this inside the HTML head; don't use async defer for now -->
<script src="https://www.gstatic.com/firebasejs/4.12.1/firebase.js"></script>
<script src="https://cdn.firebase.com/libs/geofire/4.1.2/geofire.min.js"></script>

  <script>
        
        var config = {
    apiKey: "AIzaSyCWZjRe2CK8Hu2VN35AgZOQ7lQZKcI-UWM",
    authDomain: "carrier-35d7c.firebaseapp.com",
    databaseURL: "https://carrier-35d7c.firebaseio.com",
    projectId: "carrier-35d7c",
    storageBucket: "carrier-35d7c.appspot.com",
    messagingSenderId: "827792028763"
  };

        if (!firebase.apps.length) {
            firebase.initializeApp(config);
        }
        
        //Create a node at firebase location to add locations as child keys
        var locationsRef = firebase.database().ref("locations");
        
        // Create a new GeoFire key under users Firebase location
        var geoFire = new GeoFire(locationsRef.push());
      </script>


  </head>
  <body>
    <div id="map"></div>
    <script>
      // Note: This example requires that you consent to location sharing when
      // prompted by your browser. If you see the error "The Geolocation service
      // failed.", it means you probably did not give permission for the browser to
      // locate you.

      var map, infoWindow;
      var lat, lng;
      function initMap() {
        map = new google.maps.Map(document.getElementById('map'), {
          center: {lat: -34.397, lng: 150.644},
          zoom: 18
        });
        infoWindow = new google.maps.InfoWindow;

        // Try HTML5 geolocation.
        if (navigator.geolocation) {
          navigator.geolocation.getCurrentPosition(function(position) {
            lat = position.coords.latitude;
            lng = position.coords.longitude;

            var pos = {lat: lat, lng: lng };
                _setGeoFire();
          

            infoWindow.setPosition(pos);
            infoWindow.setContent('Location found.');
            infoWindow.open(map);
            map.setCenter(pos);
          }, function() {
            handleLocationError(true, infoWindow, map.getCenter());
          });
        } else {
          // Browser doesn't support Geolocation
          handleLocationError(false, infoWindow, map.getCenter());
        }
      }

      function handleLocationError(browserHasGeolocation, infoWindow, pos) {
        infoWindow.setPosition(pos);
        infoWindow.setContent(browserHasGeolocation ?
                              'Error: The Geolocation service failed.' :
                              'Error: Your browser doesn't support geolocation.');
        infoWindow.open(map);
      }

      function _setGeoFire(){
    geoFire.set("User", [lat, lng]).then(()=>{
            console.log("Location added");
        }).catch(function(error) {
            console.log(error);
        });


}
    </script>
    <script 
    src="https://maps.googleapis.com/maps/api/js?key=AIzaSyD2nPlSt_nM7PSKD8So8anbUbBYICFWcCA&callback=initMap">
    </script>
  </body>
</html>
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