var request = new XMLHttpRequest();
request.open('GET', '/localizacoes.php', true);

request.onload = function(){
  if (request.status >= 200 && request.status < 400) {
    var data = request.responseText;

    criarMapa(data);
  }
  else{
    console.log('Deu erro!');
  }
};

request.onerror = function() {
  console.log('Deu erro!');
};

request.send();

function criarMapa(locations){

    var map = new google.maps.Map(document.getElementById('map'), {
        zoom: 10,
        center: new google.maps.LatLng(41.694808, -8.830981),
        mapTypeId: google.maps.MapTypeId.ROADMAP
    });

    var infowindow = new google.maps.InfoWindow();

    var marker, i;

    for (i = 0; i < locations.length; i++) {
        marker = new google.maps.Marker({
            position: new google.maps.LatLng(locations[i][1], locations[i][2]),
            map: map
        });

        google.maps.event.addListener(marker, 'click', (function (marker, i) {
            return function () {
                infowindow.setContent(locations[i][0]);
                infowindow.open(map, marker);
            }
        })(marker, i));
    }
}

$query   = "SELECT nome, latitude, longitude FROM pontos";
$execute = mysqli_query($conn, $query);
$result  = mysqli_fetch_array($execute);

$arrMaps [];

foreach($result as $key => $item){
    $arrMaps($arrMaps, [$item->nome, $item->latitude, $item->longitude, $key]);
}

return $arrMaps;