Backbone JS: how to disable sync for delete?

Question

I am dealing with a threaded comments collection, and when I delete a comment that has children, I do model.destroy() for this comment, and on the server side all its branches get deleted.

I wrote a function that once a node is deleted from the tree, looks for all orphans and removes them too. So when I find orphans, I run model.destroy() on them too but because they're already deleted on the server, sync returns errors.

Is there a way to disable sync for some destroy() calls?

Answer 1

This is kind of late but might work as an alternate solution for other people having the same problem.

Confronted with a very similar problem, I ended up setting all the children IDs to null before calling destroy on them. This way, backbone thinks that they are new and doesn't spawn a DELETE HTTP request to the server upon removal.

deleteParent: function() {
  this.model.children.each(function(child) {
    // Set to null so that it doesn't try to spawn a 'DELETE' http request 
    // on 'destroy' since thinks its new (hack).
    child.id = null; 
    child.destroy();
  });
  // This one DOES result in a 'DELETE' http request since it has an ID.
  this.model.destroy();
},

Answer 2

Since all the destroy method does is send a DELETE request and triggers destroy, simply triggering destroy is exactly what you're looking for.

model.trigger('destroy', model, model.collection, options);

Yeah, it feels a bit hackish, but that's pretty much all the Backbone code does anyway. If you want, and if you have a base model you extend from, you could add this as a method on that base model, and it might not feel quite so hackish.