contact.js.erb

$(document).on('turbolinks:load', function() {
  if (!(page.controller() === 'index' && page.action() === 'contact')) {
    return;
  }
  Turbolinks.clearCache();
  // only do this if you find the map_canvas_home, otherwise we don't need no maps
  if (document.getElementById("map") !== null) {
    // check to see if google map is loaded, if so, just init that map! Otherwise, create the script tag
    if (isMapsApiLoaded) {
      initMap();
    } else {
      //error is here for some reason when a link is clicked this file inserts another script
      var script = document.createElement("script");
      script.type = "text/javascript";
      script.src = "http://maps.google.com/maps/api/js?key=<%= ENV['GAPI'] %>&callback=initMap";
      document.body.appendChild(script);
    }
  }
  
});

var map;
function initMap() {
  map = new google.maps.Map(document.getElementById('map'), {
    center: {lat: -34.397, lng: 150.644},
      zoom: 8
  });
}