Question

I finished Ryan Bates #348 video for creating a JSON API using the rails-api gem. I have it working as in the example. However, in his example he has the page that calls the API in the same project. My goal is to separate out the client app from the API app.

I created a second rails app that simply includes the page that does a JSON request for the API data and a post when submitting the form. I have the client app running on localhost:3000 and the API running on localhost:4000.

Below is the client side code. It successfully submits a new deal record, but the
GET doesnt load the list of deals. When looking in the logs it appears it is requesting it as HTML. When the page was apart of the same API project, the same code was making the call as JSON in the logs.

<script src="//ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js" type="text/javascript"></script>
<script type="text/javascript" charset="utf-8">
  $(function() {
    function addDeal(deal) {
      $('#deals').append('<li>' + deal.name + '</ul>');
    }

    $('#new_deal').submit(function(e) {
      $.post('http://localhost:4000/deals', $(this).serialize(), addDeal);
      this.reset();
      e.preventDefault();
    });

    $.getJSON('http://localhost:4000/deals', function(deals) {
      $.each(deals, function() { addDeal(this); });
    });
  });
</script>

<div id="container">
  <h1>My Deals</h1>
  <form id="new_deal">
    <input type="text" name="deal[name]" id="deal_name">
    <input type="submit" value="Add">
  </form>
  <ul id="deals"></ul>
</div>

Answer 1

Because of Cross Origin Policy you have following options:

1. Use jsonp (don’t do this since you have your server 🙂 check below )
2. Manage Cross Origin Resource Sharing on server, recently I wrote answer here how to achieve this
3. You could use rails ActiveResource::Base to conect to your api, but it may be slow, and you would repeating yourself unless there is some presentation logic you need on backend. BTW, check Nibbler gem it may be somewhat better… it really depends what you need to do in backend.

Anyhow. I would avoid approach 1, its kinda overhead especially if you want to POST, PUT or DELETE, and you can allows use option 2 if you have pure javascript app running as UI. But even if you are building JS agnostic app you always need a bit of backend processing so option 3 is probably something you’d prefer.