sample rails-ajax-googlemaps-js.html.erb

<script>
          function initialize(rooms) {
            var location = { lat: 99.99, lng: 99.99 }

            if (rooms.length > 0) {
              location = { lat: rooms[0].latitude, lng: rooms[0].longitude }
            }

            var map = new google.maps.Map(document.getElementById('map'),{
              center: location,
              zoom: 12
            });

            var marker, inforwindow, windowContent;

            rooms.forEach(function(room) {
              marker = new google.maps.Marker({
                position: {lat: room.latitude, lng: room.longitude},
                map: map
              });

              windowContent = "<div class='map_price'>SR " + room.price + "</div>";
              windowContent += "<a href='http://localhost:3000/rooms/" + room.id + "'>" + room.listing_name + "</a>"

              inforwindow = new google.maps.InfoWindow({
                content: windowContent
              });

              inforwindow.open(map, marker);
            })
          }

          google.maps.event.addDomListener(window, 'load', function() {
            initialize(<%= raw @arrRooms.to_json %>)
          });