What are good modern patterns or django apps for handling server side forms that appear in a popup? By this I mean:

1. User action triggers a modal popup window.
2. The form is server generated, demand loaded.
3. In case of submit error, the server generates a new form.
4. In case of success, there's a hook so DOM elements can be updated (the main page does not reload).

Assume common libraries like jquery or bootstrap 3 are available.
Bonus points for DRY solutions: most patterns I've seen are kinda hairball, and the django ajax helpers I've looked into don't address the modal popup well or at all.