rails 5 turbolinks 5 and google maps how to?

Question

I'm using rails 5 with turbolinks 5 and trying to get google places autocomplete address form to work using the example from google's website found here

I only want to load the javascript and google maps library on this page.

What would be the correct way to get the following javascript to work with rails 5 and turbolinks 5.

<script>
  // This example displays an address form, using the autocomplete feature
  // of the Google Places API to help users fill in the information.

  // This example requires the Places library. Include the libraries=places
  // parameter when you first load the API. For example:
  // <script src="https://maps.googleapis.com/maps/api/js?key=YOUR_API_KEY&libraries=places">

  var placeSearch, autocomplete;
  var componentForm = {
    street_number: 'short_name',
    route: 'long_name',
    locality: 'long_name',
    administrative_area_level_1: 'short_name',
    country: 'long_name',
    postal_code: 'short_name'
  };

  function initAutocomplete() {
    // Create the autocomplete object, restricting the search to geographical
    // location types.
    autocomplete = new google.maps.places.Autocomplete(
        /** @type {!HTMLInputElement} */(document.getElementById('autocomplete')),
        {types: ['geocode']});

    // When the user selects an address from the dropdown, populate the address
    // fields in the form.
    autocomplete.addListener('place_changed', fillInAddress);
  }

  function fillInAddress() {
    // Get the place details from the autocomplete object.
    var place = autocomplete.getPlace();

    for (var component in componentForm) {
      document.getElementById(component).value = '';
      document.getElementById(component).disabled = false;
    }

    // Get each component of the address from the place details
    // and fill the corresponding field on the form.
    for (var i = 0; i < place.address_components.length; i++) {
      var addressType = place.address_components[i].types[0];
      if (componentForm[addressType]) {
        var val = place.address_components[i][componentForm[addressType]];
        document.getElementById(addressType).value = val;
      }
    }
  }

  // Bias the autocomplete object to the user's geographical location,
  // as supplied by the browser's 'navigator.geolocation' object.
  function geolocate() {
    if (navigator.geolocation) {
      navigator.geolocation.getCurrentPosition(function(position) {
        var geolocation = {
          lat: position.coords.latitude,
          lng: position.coords.longitude
        };
        var circle = new google.maps.Circle({
          center: geolocation,
          radius: position.coords.accuracy
        });
        autocomplete.setBounds(circle.getBounds());
      });
    }
  }
</script>

<script src="https://maps.googleapis.com/maps/api/js?key=YOUR_API_KEY&libraries=places&callback=initAutocomplete"
    async defer></script>

Answer 1

As per the documentation:

Turbolinks evaluates script elements in a page’s body each time it renders the page. You can use inline body scripts to set up per-page JavaScript state or bootstrap client-side models. To install behavior, or to perform more complex operations when the page changes, avoid script elements and use the turbolinks:load event instead.

But the reason it wasn't working for me was because in layouts/application.html.erb I had:

<%= javascript_include_tag "application", 'data-turbolinks-track' => true %>

when it should be:

<%= javascript_include_tag "application", 'data-turbolinks-track': 'reload' %>