URLs and side effects (Django)
I agree that #2 is a better approach. 
But take care with overloading the submit <input /> with different methods -- if a user is using it with keyboard input and hits enter, it won't necessarily submit the <input /> you're expecting. Either disable auto-submit-on-enter, or code things up so that if there is more than one thing that submit can do, there's another field that sets what the action should be (eg a 'delete' checkbox, which is tested during a request.POST) 
If you went with #1 I'd say that a GET to a POST-only view should be met with a 405 (method not supported) - or, failing that, a 404.
I'm wondering if it's considered okay (particularly, in Django) to have a URL that's only intended for actions with side effects, that's only intended to be accessed by POST, and that is basically invisible to the user. Let's say, for the sake of making this concrete, I have a little messaging system on my site, and from their inbox, a user should be able to do a bunch of things like:

Delete a message
Mark a message as read
Report a message as spam

With all of those things causing a page refresh, but leading back to the same page. I'm wondering how to design my URLs and views around this. I see (at least) two options, and I have no idea which is more idiomatic.
Option 1)
Have a separate URL and view for each action. So, /inbox/delete-message/ maps to views.delete_message, and so on. At the end of each of those views, it redirects back to /inbox/.
I like the way things are clearly separated with this option. If a user somehow finds themselves sending a GET request to /inbox/delete-message/, that presents a sort of weird situation though (do I throw up an error page? silently redirect them?).
Option 2)
Use the same URL and view for each action, and have a POST parameter that identifies the action. So I would have one rather long inbox view, which would have a bunch of if statements testing whether request.POST['action'] == 'delete', or request.POST['delete'] == 'true' or whatever.
This option feels less clean to me, but I also feel like it's more common.
Which would be preferred by Djangonauts? Or is there another option that's better than either of the above?