Backbone Model.destroy() Limited

I'm attempting to bulk delete a collection of backbone models like so... collection.each(function(model, i){ model.destroy(); }); I'm finding that when the each loop contains mo

Solution 1:

Is this an intentional limitation within Backbone to keep you from deleting 1000 records in one shot or a browser limitation on the number of relatively simultaneous DELETE methods?

No.

The problem is you are munging the collection on each iteration. Consider the following.

Say you start off with a collection of 10 models:

// pretend this collection has 10 models [m0,m1,m2,m3,m4,m5,m6,m7,m8,m9]
collection.each(function(model,i) {
  model.destroy();
});

On your first iteration, your collection.length === 10 and the arguments to collection.each will be m0 and 0. So you call, m0.destroy() which lives at index 0.

At the end of the first iteration your collection contains the following models

[m1,m2,m3,m4,m5,m6,m7,m8,m9]

The following is where the problem starts:

Now for your second iteration your collection.length === 9 . The each function is now on its second iteration and grabbing the model at index of 1, and that's where model 2 lives. So the arguments into each are m2,1. You then call m2.destroy() and remove that from the collection.

At the end of the second iteration your collection contains the following:

[m1,m3,m4,m5,m6,m7,m8,m9]

The third iteration, your index will be 2 and m4.destroy() will be called. leaving you with:

 [m1,m3,m5,m6,m7,m8,m9].

This happens until the index is greater than collection.length and then stops. Leaving you with unwanted models in your collection.

The following should work for you:

while ( (model=collection.shift()) ) {
  model.destroy()
}

Solution 2:

Agree to previous answers, you are not allow to do that.

Very quickly, what I would do in that case:

collection.map(function (model) {
  return model.id;
}).each(function (id) {
  collection.get(id).destroy();
});

Solution 3:

Have you tried removing the model first from the collection using Backbone.Collection.remove? I think by calling model.destroy() you are breaking the internal array of models handled by the collection.

Try it like this:

collection.each(function(model, i) {
    collection.remove(model);
    model.destroy();
});