Set latitude and longitude into a cookie for a Rails server

controller.rb

require 'pp'

class SomeController < ApplicationController
  def omg
    # cookies.delete 'latlon'
    @cookies = cookies.to_h

    # now probably move these to helper methods in application controller
    @latitude, @longitude =
      cookies['latlon'].to_s.split('|')
      .map(&:to_f)
  end
end

view.html.erb

<h2>Was JS run?</h2>

<div id="was-js-run">No</div>


<h2>Latitude / Longitude</h2>

<p>(<%= @latitude %>, <%= @longitude %>)</p>



<h2>Cookies (from server):</h2>


<pre><%= @cookies.pretty_inspect %></pre>

<script>
  // found the regex here: https://developer.mozilla.org/en-US/docs/Web/API/Document/cookie
  var match = document.cookie.match(/(?:(?:^|.*;\s*)latlon\s*\=\s*([^;]*).*$)|^.*$/);
  var cookieValue = (match && match[1]);
  if(cookieValue)
    console.log("Looks like: " + cookieValue);

  if(!cookieValue && navigator.geolocation) {
    navigator.geolocation.getCurrentPosition(function(geoPosition) {
      var coords  =  geoPosition.coords
      document.cookie = ("latlon=" + coords.latitude + "|" + coords.longitude);
      $('#was-js-run').text('YES!').css('background-color', 'green')
    });
  }
</script>