Question

I’ve been using JSON to handle AJAX functionality in my rails applications ever since I heard about it, because using RJS/rendering HTML “felt” wrong because it violated MVC. The first AJAX-heavy project I worked on ended up with 20-30 controller actions tied directly to specific UI-behaviors and my view code spread over controller actions, partials and rjs files. Using JSON allows you to keep view specific code in the view, and only talk to view agnostic/RESTful controller actions via AJAX to get needed data.

The one headache I’ve found from using pure JSON is that you have to ‘render’ HTML via JS, which in the case of AJAX that has to update DOM-heavy elements, can be a real pain. I end up with long string building code like

// ...ajax 
success: function(records){
  $(records).each(function(record){
    var html = ('<div id="blah">' + record.attr +
      etc +
    ')
  })
}

where etc is 10-15 lines of dynamically constructing HTML based on record data. Besides of the annoyance, a more serious draw back to this approach is the duplication of the HTML structure (in the template and in the JS).* Is there a better practice for this approach?

(My motivation for finally reaching out is I am now tasked with updating HTML so complex it required two nested loops of Ruby code to render in the first place. Duplicating that in Javascript seems insane.)

• One thing I’ve considered is loading static partial files directly from the file system, but this seems a bit much.

Answer 1

Just happened to find exactly what I was looking for: Jaml