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.fetch() collection backbone.js doesn't work

I want to call API URL to get data, and pass it to a view, but encounter an error when using fetch property:
Uncaught TypeError: Cannot read property 'localStorage' of undefined
at G.d.Backbone.sync (backbone.localStorage-min.js:8)
at G.d.fetch (backbone-min.js:23)
at G.d.initialize (backbone:120)
at G.d.g.Collection (backbone-min.js:18)
at new G.d (backbone-min.js:38)
at backbone:137
The code:
var app = {};
app.postCollection = Backbone.Collection.extend({
url: 'https://jsonplaceholder.typicode.com/comments',
initialize: function(){
this.fetch({
success: this.fetchSuccess,
error: this.fetchError
});
},
fetchSuccess: function (collection, response) {
console.log('Collection fetch success', response.data);
/*console.log('Collection models: ', this.models);*/
},
fetchError: function (collection, response) {
throw new Error(" fetch error");
}
});
try {
app.postcollection = new app.postCollection();
}
catch (e) {
console.log(e.message);
}
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js" type="text/javascript"></script>
<script src="http://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.3.3/underscore-min.js" type="text/javascript"></script>
<script src="http://cdnjs.cloudflare.com/ajax/libs/backbone.js/0.9.2/backbone-min.js" type="text/javascript"></script>
<script src="http://cdnjs.cloudflare.com/ajax/libs/backbone-localstorage.js/1.0/backbone.localStorage-min.js" type="text/javascript"></script>

You are using an old version of localStorage. Update to a new version, for example https://cdnjs.cloudflare.com/ajax/libs/backbone-localstorage.js/1.1.16/backbone.localStorage.js
Also, you need to specify localStorage property on the collection like localStorage: new Backbone.LocalStorage("SomeCollection"),
Working JSFiddle

Backbone: how to load a Collection in the view (inc require)

I am trying to load data from an API into a view. However the data doesn't turn up in my view.
I tried getting the collection information in de router, as well as in the model.
However the date won't even console.log the data. Let alone that I can load the data into the view.
I am using require to load the JavaScript files. Can you have a look and see what I am doing wrong here?
I do see this console.log:
console.log("People Collection is initialized");
And I can also see the page loaded and the json. But not the console.log of the data in the url function... In fact I get this error in the console:
Error: A "url" property or function must be specified
In the Backbone Router:
var OF = OF || {};
OF.AdminRouter = Backbone.Router.extend({
routes: {
"users": "goToUsers",
"users/*other": "goToUsers"
},
goToUsers: function() {
require(['./models/users', './views/users_view', './views/menu_view', './collections/user_collection'], function(UsersMdl, UsersView, MenuView, UsersCollection) {
OF.usersView = new OF.UsersView;
OF.usersView.render();
});
}
});
The Collection:
var OF = OF || {};
OF.UsersCollection = Backbone.Collection.extend({
initialize: function() {
console.log("People Collection is initialized");
},
url: function() {
var that = this;
var sendObj = {
"admin": OF.login.attributes.admin,
"session": OF.login.attributes.session
};
$.ajax({
url: 'php/api/users/',
type: "POST",
dataType: "json",
data: sendObj,
success: function(data) {
console.log(data);
},
error: function(data) {
console.log("ERR: " + data);
}
});
},
model: OF.UsersMdl
});
The Model:
var OF = OF || {};
OF.UsersMdl = Backbone.Model.extend({
default: {
username: '',
homefoldersize: '',
email: ''
},
initialize: function(){
//on change functions can be done here
OF.usersCollection = new OF.UsersCollection();
OF.usersCollection.fetch();
},
result: {
success: false,
message: ''
},
validate: function(att) {
}
});
The View:
var OF = OF || {};
OF.UsersView = Backbone.View.extend({
el: '#content',
remove: function() {
this.$el.empty();
this.stopListening();
return this;
},
initialize: function() {
//set the new address variable.
OF.usersMdl = OF.usersMdl || new OF.UsersMdl();
},
render: function() {
/*
//first check if you are allowed to see this page
if (!OF.login || !OF.login.isValid()) {
OF.router.navigate('login', {trigger: true});
return;
}
*/
//save this in that
var that = this;
//when importing of login page (and fill it with info) is done
$.when(OF.template.get('users-usersField', function(data) {
var htmlSource = $(data).html();
var template = Handlebars.compile(htmlSource);
var compiled = template(OF.usersMdl.attributes);
//now place the page
that.$el.html(compiled);
//then start the menu
})).then(function(){
setTimeout(function(){
OF.menuView = new OF.MenuView;
OF.menuView.render();
}, 100);
});
$('#logout').show();
}
});
Thanks.

It seems to call the initialize of the collection twice and then continues to call the json function.
In your model's initialization you have
OF.usersCollection = new OF.UsersCollection();
OF.usersCollection.fetch();
But when you fetch your collection, it's going to initialize models for every result it gets back ... which will then trigger fresh collection fetches.
You don't need to create collections for your models inside your models, especially if the model is being created by the collection. Whenever you add a model to a collection (including when the collection creates the model after a fetch) the collection will associate itself with the model.
The general order of things should be:
You define a url function on your collection which returns the URL where you can get the (raw JSON) models of that collection.
You instantiate that collection, and then call fetch on the instance
The collection makes an AJAX call (which you can affect by overriding fetch or sync) and gets back the raw JSON for all of the models.
The collection instantiates new models for each result it gets back; those models are automatically added to the collection, and their .collection is automatically set to the collection.
Once OF.usersCollection.fetch().done(function() {... you can have your views start doing things, as your collection should now be all set.

Backbone Collection Not firing Add Event

So i have a problem whereby I have a backbone collection that am using to create function to save data to a REST API. The data is saved to the server and a model is added to the current collection but then the add event for the collection is not fired.Below are snippets of the code
The views initialize function
intialize : function() {
this.listenTo(this.collection, 'add', this.updateList);
},
The updateList function only does a console log.The views function that saves data using the collection is:
cards = this.collection;
debugger
cards.create(data, {
success : function(model, response) {
console.log("success on saving card");
console.log(response);
console.log("Updating list");
console.log(cards);
},
error : function(model, response) {
console.log("error on saving card");
console.log(model);
console.log("response");
console.log(response);
}
})
return false;

Try this code in your view:
initialize: function() {
this.collection.on('add', this.updateList, this);
}
Or:
var someCollection = new SomeCollection();
var view = new SomeView({collection: someCollection});
view.listenTo(someCollection, 'add', view.updateList);

why don't you just use: this.model.on('change', doAction, this); inside the view? if I understood correctly, this is a better solution since your model is changing.
plus, I couldn't find anywhere a place where the ListenTo() is mandatory over the On() function, can you tell me where you saw it?

jquery.couchdb.js Ajax success/error not being called

I'm using jquery.couchdb.js to query my CouchDB database. The view I want to query has both map and reduce functions within. When sending the basic query as shown below:
$(document).ready(function() {
view_name = db_name+'/jobs_by_mod_stat'
options = {'group': 'true' , 'reduce': 'true' };
mod_stat = {};
$db.view(view_name , {
success: function(data) {
console.log(data)
for (i in data.rows) {
console.log(data.rows[i].value);
}
},
error: function(e) {
alert('Error loading from database: ' + e);
}
});
});
I see a sensible log for the data, indicating the query has been successful. However, changing the line:
$db.view(view_name , {
To
$db.view(view_name , options, {
I don't get a success outcome from the Ajax query, but an error message is not shown either. Firebug shows the query being sent, and the JSON data returned looks sensible:
{"rows":[
{"key":["template","completed"],"value":2},
{"key":["template","running"],"value":2},
{"key":["template","waiting"],"value":6}
]}
But the success function is not entered. Any ideas why I'm seeing this behaviour, I did wonder if it's a bug in jquery.couch.js (I have couchdb 1.1.0).
Cheers.

I've had a bit of trouble myself with the list function, until I went and looked through the source code of jquery.couch.js (the online documentation I found at http://bradley-holt.com/2011/07/couchdb-jquery-plugin-reference/ seems to be outdated).
Basically, the parameters for view and list are different, the list having an extra parameter for the options, instead of having everything under the same parameter as with views.
View:
$.couch.db('yourdb').view('couchapp/' + viewName, {
keys: ['keys here'],
success: function (data) {
}
});
List:
$.couch.db('yourdb').list('couchapp/' + listName, viewName, {
keys: ['keys here']
}, {
success: function (data) {
}
});

Backbone Sync with a mashup of models in Rails

I have a rails controller which sends a mash-up of models as a global json object. Something like this
{
dogs : { species: {}, ...},
cats : { food: {}, ...},
foxes : { },
...,
...
}
On my client side, I have all these entities neatly segregated out into different backbone models and backbone collections.
On some onchange event, I need to send a mashup of some model attributes back to the server as a HTTP POST request and the server sends a response which again spans values across a few models.
How do I setup Backbone.sync to deal with such an ajax scenario? I do not want to change the rails backend because its quite a steady implementation. Or do I make vanilla $.ajax requests through jQuery in one of my backbone views and handle it in a callback on ajax success/failure?

I think there are a couple of ways to do this via backbone. I think I'd start out with a model to represent the mashup:
var MashupModel = Backbone.Model.extend({
});
Then you can pass in any models like you would normally (or a collection for that matter):
var my_mash = new MashupModel({
dog: dogModel.toJSON(),
cat: catModel.toJSON(),
foxes: foxCollection.toJSON()
});
// do stuff if you need...
Then do what you want when the response comes back like normal:
my_mash.save({}, {
success: function(model, response) {
// do stuff here to put new data into the proper models / collections
},
error: function() { alert("I FAIL!"); }
});
That's all well and good... however, I think it would be better to push the above down into the MashupModel object instead of at the request level. Again, several ways:
var MashupModel = Backbone.Model.extend({
initialize: function(attrs) {
// can't remember the actual code, but something along the lines of:
_.each( attrs.keys, function(key) {
this.set(key, attrs.key.toJSON();
});
},
save: function(attrs, opts) {
var callback = opts.success;
opts.success = function(model, response) {
// do your conversion from json data to models / collections
callback(model, response);
};
// now call 'super'
// (ala: http://documentcloud.github.com/backbone/#Model-extend)
Backbone.Model.prototype.set.call(this, attrs, opts);
}
});
Or you could override toJSON (since backbone calls that to get the attrs ready for ajax):
// class definition like above, no initilize...
...
toJSON: function() {
// again, this is pseudocode-y
var attrs = {};
_.each( this.attributes.keys, function() {
attrs.key = this.attributes.key.toJSON();
});
return attrs;
}
...
// save: would be the same as above, cept you'd be updating the models
// directly through this.get('dogs').whatever...
Now, you can just do:
var my_mash = new MashupModel({
dog: dogModel,
cat: catModel,
foxes: foxCollection
});
// do some stuff...
my_mash.save({}, {
success: function(model, response) {
// now only do stuff specific to this save action, like update some views...
},
error: function() { alert("I FAIL!"); }

it would be possible, but may be difficult to modify backbone.sync to work with this structure. i'd recommend going with plain old jquery $.ajax requests. then on success, pull the info apart and populate your collections.
$.get("/whatever", function(data){
catCollection.reset(data.cats);
dogCollection.reset(data.dogs);
// etc
});
data = {};
data.cats = catCollection.toJSON();
data.dogs = dogCollection.toJSON();
// etc
$.post("/whatever", data);