BackboneJS model.url using collection.url - backbone.js

From my understanding the default behavior of Backbone JS Models are to return the Collection's URL, unless the model has a urlRoot specified. I can't seem to get the behavior to work.
From the documentation:
model.url() ... Generates URLs of the form: "[collection.url]/[id]" by default, but you may override by specifying an explicit urlRoot if the model's collection shouldn't be taken into account.
Here is my collection, and model respectively:
var MyCollection = Backbone.Collection.extend({
model: Model,
initialize: function(options){
this.options = options || {};
},
url: function(){
return "/theurl/" + this.options.param;
}
});
return MyCollection;
...
var MyModel = Backbone.Model.extend({
urlRoot: '/theurl',
initialize: function() {
}
});
return MyModel;
When a model is loaded without a collection, it works great and submits to /theurl, but when it's loaded into a collection, all methods submit to /theurl/param/.
If I'm understanding the documentation correctly, the urlRoot of the Model should override this behavior; and even then the models url should be /theurl/param/{MODEL-ID}.
Any ideas on what I'm missing/misunderstanding?
...
PS: The model: Model from the collection is brought in via RequireJS

It will always use the collection's url even if you have urlRoot specified.
The reason for urlRoot is so you can use it in an override, or if the model happens to not be in a collection ( for example maybe it gets removed, but still exists on the client).
So if you want to fetch or save the model and override the url generated by the collection you'll need to pass the urlRoot into these methods explicitly as an option. For example:
yourModel.save({ url: yourModel.urlRoot });
I agree the documentation is confusing and this caught me out recently too.

UrlRoot should be a function and model must have attributeId defined.
If you define your model like this all operation will be working if model is in collection or not.
Backbone add modelId at the end of URL that is returned by urlRoot function.
var MyModel = Backbone.Model.extend({
attributeId: 'myModelId'
urlRoot: function() {
return '/theurl';
},
initialize: function() {
}
defaults: {
myModelId: null
}
});

In the model, try using:
url: function() {
return 'your url goes here';
}

Related

Backbone.js / require.js - Override model function to work with backend as a service

Good morning guys. I have a little understanding problem with backbone.js. i have a javascript sdk from a backend as a service with some getter and setter methods to get datas from this platform.
I have load this javascript sdk with require.js an it´s work fine. Now i need to create some models that work with this getter and setter methods to get this data to my collection an finally to my view. I do not have any clue...maybe someone have the right idea for me.
This is my current model:
define(['jquery','underscore','backbone'], function($,_,Backbone) {
var holidayPerson = Backbone.Model.extend({
initialize: function() {
console.log("init model holidayPerson");
this.on("change", function(data) {
console.log("change model holidayPerson"+JSON.stringify(data));
});
}
});
return holidayPerson;
});
Actually i create an instance of my model in my view:
define(['jquery','underscore','backbone','text!tpl/dashboard.html','holidayPerson','apio'], function($,_,Backbone,tpl, holidayperson, apio) {
template = _.template(tpl);
var usermodel = new holidayperson();
var dashboardView = Backbone.View.extend({
id: 'givenname',
initialize: function() {
console.log("dashboard view load");
usermodel.on('change', this.render);
var user = new apio.User();
user.setUserName('xxx');
user.setPassword('xxx');
apio.Datastore.configureWithCredentials(user);
apio.employee.getemployees("firstName like \"jon\" and lastName like \"doe\"", {
onOk: function (objects) {
console.log("apio: " + JSON.stringify(objects));
usermodel.set({mail: objects[0]['data']['mail'],lastname: objects[0]['data']['lastName'], username: objects[0]['data']['userName'], superior: objects[0]['data']['superior']});
}
});
},
render: function() {
console.log("render dashboard view");
console.log(usermodel.get('mail'));
console.log(usermodel.get('lastname'));
this.$el.html(template());
return this;
}
});
return dashboardView;
});
I think this not the right way...can i override the getter and setter method from this model ? Or maybe the url function ? Anyone now what is the best practice ?
Thanks a lot :-)
First of all, make sure that your render operation is asynchronous, as your API call will be and the usermodel params won't be set until that operation completes. If you render method fires before that, it will render the empty usermodel, since the data will not be there yet.
Second, a model need not fetch its own data, in my opinion. If you are going to have multiple users, you could use a collection to hold those users and then override the collection's sync method to handle the fetching of data from the API, but if there's no collection, it seems logical to me to have a method that does the data fetching and setting thereafter, as you've done.

How to fetch the model in a view with a dynamic url defined in a view

I am using backbone.js in my app. My model named MyModel is
Backbone.Model.extend({
urlRoot: 'home'
});
Need to fetch model with url "home/abc/xyz" where "abc" and "xyz" are dynamic in my view. I did the following
var model = new MyModel({id:'abc/xyz'});
model.fetch();
but its not working.
It goes to url "home/abc?xyz".
How should i solve this issue?
Here is the url function of Backbone.Model which is responsible for such kind of behavior in Backbone:
url: function() {
var base =
_.result(this, 'urlRoot') ||
_.result(this.collection, 'url') ||
urlError();
if (this.isNew()) return base;
return base.replace(/([^\/])$/, '$1/') + encodeURIComponent(this.id);
}
As you can see encodeURIComponent(this.id) will encode your id, so you can't pass and '/' -> '%2F'.
You always can rewrite this function, but I guess it's not the best idea, cause it can break another things.
I can suggest you another approach:
Just define urlRoot of your model as function and there do your job:
var yourModel = Backbone.Model.extend({
defaultUrl: 'home',
urlRoot: function () {
return defaultUrl + this.get('yourUrlAttribute');
}
});
Just pass the yourUrlAttribute as model attribute when creating it and fetch the model.
Having in mind this approach and that Backbone.Model will append encoded 'id' as the last part of URL (when you fetching model) you can get what you want.

How to retrieve an object from Parse.com after saving it

I'm creating an application for Phonegap using Backbone framework and Parse.com as backend service. I create an object with Parse.com (corresponding to Backbone models).
This object has a saveDraftToP() method that calls the Parse.com function save().
After this method is called from a view, I'd like to retrieve the updated object.
To do so I'm binding the 'change' event to the model but the Parse assigned ID is undefined.
Here is the code of the model:
var Match = Parse.Object.extend("Match", {
states: {'DRAFT': 0, 'RUNNING': 1, 'ENDED': 2},
saveDraftToP: function () {
var self = this;
this.save({
user: Parse.User.current(),
ACL: new Parse.ACL(Parse.User.current()),
state: self.states.DRAFT
}, {
success: function (result) {
self = result;
},
error: function (e) {
}
});
}
});`
And here is the code for the view:
var vmNuovaPartita = Parse.View.extend({
template: Handlebars.compile(template),
model: new Match(),
collection: new HintCollection(),
initialize: function () {
this.bind("change:model", console.log(this.model.id) , this);
},
render: function (eventName) {
var match = this.model.toJSON();
$(this.el).html(this.template(match));
return this;
}
});
I'm not quite sure why you have a save function wrapped in another save-like function. :-)
Say you have something like myMatch which is an object.
Through your UI, a button click saves the object data. You can just use myMatch.save({attr:val, ...}) straight out of the box. Backbone (and Parse) by default are optimistic. That means, you it will set the values of the model with the expectation that persisting to the server will succeed.
Thus, you don't need to retrieve anything extra. You already have the model in it's most current state.
To have a model view that responds to these changes, I'd design the view a little differently.
var vmNuovaPartita = Parse.View.extend({
template: Handlebars.compile(template),
initialize: function () {
this.model.on('change', this.render);
},
render: function (eventName) {
var match = this.model.toJSON();
$(this.el).html(this.template(match));
return this;
}
});
var myView = new vmNuovaPartita({
model: myModel
});
I'd initialize the model outside of the view, then pass it in as an option when you generate a new view. When you pass a model in as an option, it's special and will be attached directly to the view ... view.model which you can refer inside your view code as this.model
In the init we place a listener on the model for change events, then fire off a rerender of the view. Or a nicer way to go about this sort of thing is to throw in the newer Backbone Events with the .listenTo() method.

Use a flag in a Backbone Model but not as a property (that gets saved)

So what I'm trying to achieve is when the user wants to edit/view an item (the Model), I send them to a URL, create a new Model instance and call .fetch on it before loading up the relevant view and handing it the new Model.
For various reasons, I need to know whether the user is editing or viewing the item (the Model), so my first attempt was this:
app.Models.Quote = Backbone.Model.extend({
idAttribute: 'Number',
initialize: function() {
this.editMode = false;
},
url: function() {
return app.Settings.apiUrl() + '/quotes/' + this.id;
}
});
So in various places in the view/edit View, I could do:
if(this.model.editMode){ //foo }
However this doesn't seem to be working at all, ie. the editMode isn't found (undefined).
What are people's general solution/advice for achieving this?
It is quick example that this property is working : http://jsfiddle.net/damian0o/u9rrh/
Make sure that this is your view instance by adding something like
var self = this;
or using undersocore method
_.bindAll(this,"");
in view initializing method
Try adding editMode as a property of the Model. You can now do this.model.editMode and inside your model, you can refer to editMode as this.editMode.
app.Models.Quote = Backbone.Model.extend({
idAttribute: 'Number',
editMode: false, // this initializes the value to false
initialize: function() {
//this.editMode = false;
},
url: function() {
return app.Settings.apiUrl() + '/quotes/' + this.id;
}
});

backbone.js - how can i fetch local or server data

I am very new to backbone.js, to try it out I made a function to append an element using my array. But I don't know how to fetch the same from server or my local path.
I tried with some tutorial but still I couldn't get any good result. Can any one correct my function to fetch the data from local folder or server?
code :
this is my local path: '..data/data.json'
(function($){
var student = [
{name:'student1'},
{name:'student2'},
{name:'student3'}
]
var model = Backbone.Model.extend({
defaults:{
name:'default name'
}
});
var collection = Backbone.Collection.extend({
model:model
});
var itemViews = Backbone.View.extend({
tagname:'li',
render:function(){
this.$el.html(this.model.get('name'));
return this;
}
})
var view = Backbone.View.extend({
el: $("#contacts"),
initialize:function(){
this.collection = new collection(student);
this.render();
},
render:function(){
var that = this;
_.each(this.collection.models, function(item){
that.renderName(item);
})
},
renderName:function(item){
var itemView = new itemViews({model:item});
this.$el.append(itemView.render().el);
}
});
Collections have the url property which links to the url where the models can be fetched (in a proper JSON format of course).
If you have a RESTful API you can tie them directly to a collection on your backend.
In your case you can modify the collection definition as follows
var collection = Backbone.Collection.extend({
model:model,
url: '..data/data.json' //OR WHATEVER THE URL IS
});
Then when instantiating your collection you have to call the fetch() method to fill in the collection.
myCollection = new collection();
myCollection.fetch();
For more information see this post
Backbone will call GET, POST, DELETE, etc on that same url depending on what needs to be sent or received from the server. So if you are building the REST api, your controller or router should route the appropriate functions to those methods. See below for exact mapping:
create → POST /collection
read → GET /collection[/id]
update → PUT /collection/id
delete → DELETE /collection/id
As a side note, if you have no control over the JOSN that is returned from the server, you can format it in any format you like in the parse function.
parse: function(response) { return response.itemYouWantAdded; }
This would be the case if your server is returning an object within an object, such as twitter feeds.
Or you could simply populate the model from the response manually in the parse function
parse: function(response) { var tmpModel = {
item1:response.item1,
item2:response.item2
};
return tmpModel; }
Hope this helps.
You can set a URL for your model or for your collection. Then when you run fetch it will read your JSON straight into either a single model or a collection of models. So in your case, your collection might look like
var collection = Backbone.Collection.extend({
url: '..data/data.json',
model: model
});
collection.fetch(); // Could also use collection.reset()
You just need to make sure your JSON is formatted properly to match your model's attributes.

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