How to mass assign all attributes of a Backbone model? - backbone.js

Question

I would like to update the User model whenever signIn was successful. It includes the id assign by the backend which has not been present in the model before.
MyApp.module("User", function(User, App, Backbone, Marionette, $, _) {
User.Controller = Backbone.Marionette.Controller.extend({
initialize: function() {
this.model = new MyApp.User.Model();
},
signIn: function(credentials) {
var signInData = { user: credentials };
var self = this;
App.session.signIn(signInData, {
success: function(model, response, options) {
self.updateUserModel(model);
},
error: function(model, xhr, options) {}
});
},
updateUserModel: function(model) {
// TODO Update all attributes, including new onces e.g. id.
}
});
});
How would you update all attribtues at once? I know that I manually can set every single attribute but this seems to be wrong since the list of attributes may change over time.
Generally, I would expect such an update(model) method in the User model.
When I use Backbone's model.set() method as suggested by nikoshr and john-4d5 ...
signIn: function(credentials) {
var signInData = { user: credentials };
var self = this;
App.session.signIn(signInData, {
success: function(model, response, options) {
self.model.set(model);
},
error: function(model, xhr, options) {}
});
},
... the id attribute is copied into this.model but other properties such as name are missing.
The model returned in the success callback looks like this:
_changing: false
_pending: false
_previousAttributes: Object
attributes: Object
bind: function (name, callback, context) {
close: function (){
constructor: function (){ return parent.apply(this, arguments); }
created_at: "2013-07-22T19:03:24Z"
email: "user#example.com"
id: 3
initialize: function () {
listenTo: function (obj, name, callback) {
listenToOnce: function (obj, name, callback) {
logout: function () {
model: child
name: "Some User"
off: function (name, callback, context) {
on: function (name, callback, context) {
once: function (name, callback, context) {
options: Object
signIn: function (credentials) {
signUp: function (credentials) {
stopListening: function (obj, name, callback) {
trigger: function (name) {
triggerMethod: function (event) {
unbind: function (name, callback, context) {
updated_at: "2013-08-05T13:20:43Z"
user: Object
__proto__: Object
changed: Object
cid: "c3"
id: 3
__proto__: Surrogate

Answer 1

You are moving around a Backbone.Model,
Model.set accepts a hash of attributes,
you can convert a Backbone.Model to a hash of attributes with Model.toJSON
You could write your callback as
success: function(model, response, options) {
self.model.set(model.toJSON());
}

Answer 2

You can simply use set, giving the other model's attributes property value (an object with all the attribute values) as an argument.
self.model.set(model.attributes);

Answer 3

You can use this.model.set(model) as #nikoshr said. Iterate over the attributes and setting each one will do the same thing as model.set already does. Refer to the backbone's model.set function:
// Set a hash of model attributes on the object, firing `"change"`. This is
// the core primitive operation of a model, updating the data and notifying
// anyone who needs to know about the change in state. The heart of the beast.
set: function(key, val, options) {
var attr, attrs, unset, changes, silent, changing, prev, current;
if (key == null) return this;
// Handle both `"key", value` and `{key: value}` -style arguments.
if (typeof key === 'object') {
attrs = key;
options = val;
} else {
(attrs = {})[key] = val;
}
[...]
// For each `set` attribute, update or delete the current value.
for (attr in attrs) {
val = attrs[attr];
if (!_.isEqual(current[attr], val)) changes.push(attr);
if (!_.isEqual(prev[attr], val)) {
this.changed[attr] = val;
} else {
delete this.changed[attr];
}
unset ? delete current[attr] : current[attr] = val;
}
[...]
}
Another option is to instantiate a new model:
this.model = new MyApp.User.Model(model);