Exclude model properties when syncing (Backbone.js)

Question

Is there a way to exclude certain property from my model when I sync?

For example, I keep in my model information about some view state. Let's say I have a picker module and this module just toggle a selected attributes on my model. Later, when I call .save() on my collection, I'd want to ignore the value of selected and exclude it from the sync to the server.

Is there a clean way of doing so?

(Let me know if you'd like more details)

Answer 1

This seems like the best solution (based on @nikoshr referenced question)

Backbone.Model.extend({      // Overwrite save function     save: function(attrs, options) {         options || (options = {});         attrs || (attrs = _.clone(this.attributes));          // Filter the data to send to the server         delete attrs.selected;         delete attrs.dontSync;          options.data = JSON.stringify(attrs);          // Proxy the call to the original save function         return Backbone.Model.prototype.save.call(this, attrs, options);     } }); 

So we overwrite save function on the model instance, but we just filter out the data we don't need, and then we proxy that to the parent prototype function.

Answer 2

In Underscore 1.3.3 they added pick and in 1.4.0 they added omit which can be used very simply to override your model's toJSON function to whitelist attributes with _.pick or blacklist attributes with _.omit.

And since toJSON is used by the sync command for passing the data to the server I think this is a good solution as long as you do not want these fields wherever else you use toJSON.

Backbone.Model.extend({     blacklist: ['selected',],     toJSON: function(options) {         return _.omit(this.attributes, this.blacklist);     }, });