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Backbone.js dynamic URL problems

I have this Backbone.js model and view code, where I am trying to get a value from a text field, and fetch data from REST api based on this value. I am having problems modifying the base URL.
Model with base URL:
var TodoItem = Backbone.Model.extend({
urlRoot : 'http://localhost/Codeigniter/index.php/testcontroller',
initialize: function(){
this.set('id', 1);
},
defaults: {
name: '',
age: ''
}
});
var todoitem = new TodoItem({name: "name"});
Function where I am setting new URL:
getUrl: function(celebname){
var urlstr = "http://localhost/Codeigniter/index.php/testcontroller/getdatabasedata?searchvalue="+celebname;
return urlstr;
},
Function that fetches data from the REST api.
getdata: function (event) {
var celebname = $('#celebname').val();
this.model.set({name: celebname});
this.model.save({}, { urlRoot: this.getUrl(celebname)});
this.model.fetch();
},
At the moment I am getting this error:
GET http://localhost/Codeigniter/index.php/testcontroller/1
I cannot change the base url using the getURL function to search for the value from input field.Instead is using the base url and the id at the end.
If I am not setting out the ID in the initialize function of the model, then I get this error:
POST http://localhost/Codeigniter/index.php/testcontroller/getdatabasedata?searchvalue=Rome
From what I have read online this is because there is no id assigned to the model.
How can I get the input field value, build the URL, and fetch data using the GET method?
Thank you

Backbone works incredibly well with true RESTful APIs. Part of the issue here is that the API you have does not really map well with the Backbone model i.e. it's not exactly RESTful. As a result, you're going to have to resort to "hacks" to have the client and server get along. Dynamically modifying the route of a model is an example of one such hack.
What might help get you better answers is if you could elaborate a bit more on the use-case you have in mind.
From what I can tell, you're not really trying to persist a TodoItem. Rather, you're trying to pre-populate it with some base data. If this is true, then you really should not be doing a save -- you should just be doing a fetch.
getdata: function (event) {
var celebname = $('#celebname').val();
var id = this.model.id;
this.model.id = 'getdatabasedata';
this.model.fetch({data: {searchvalue: celebname}});
this.model.id = id;
}
Passing the data option will tell jQuery to use it as a query string param.
Again, this is very hacky and I would not recommend it, but it will accomplish what you're trying to do.

how to pass an id containing / in backbone.js

HI my basic model which fetches data from server is working perfect. I want to implement a search feature. When user enters any data the request goes to browser and desired model is returned.
var Book = Backbone.Model.extend({
urlRoot: '/books'
});
render: function(options) {
books = new Book({id:options.name});
books.fetch();
}
where
name = "search/"+dynamic_data;
Request URL that is being formed when i pass --> 'life' in variable dynamic_data
http://host/path/search%2Flife
Request URL that i want
http://host/path/search/life
How can I encode/escape my string to achieve the desired result. I have tried escape(), encodeURI(), encodeURIComponents
A workaround to solve this is create one more model with urlRoot as /books/search and pass just name . I don't think this is correct. Should I use this ?

According to your additionnal precisions stating that life is actually a book name...
It looks like Backbone is better integrated with RESTful API's. In REST, your urls should not contain verbs and to search books, you would do a GET /books/?name=life.
In that case, you would only have to define a Backbone.Collection like:
var BooksCollection = Backbone.Collection.extend({
model: Book,
url: '/books'
});
The to fetch books:
var books = new BooksCollection();
books.fetch({data : {name: 'life'}}); //GET /books/?name=life
If you really want your search operation to target /search/:name, you will have to check the Backbone.Collection api, but I think you will want to look at http://backbonejs.org/#Sync
You could override your collection's sync method to something like:
Backbone.Collection.extend({
...
sync: function (method, model, options) {
//for read operations, call the search url
if (method === 'read') {
options.url = '/search/' + options.data.name;
delete options.data.name;
}
//call the default sync implementation
return Backbone.Collection.prototype.sync.apply(this, arguments);
}
});
In this cased calling books.fetch({data : {name: 'life'}}); will result in GET /books/life.
Here's a fiddle that shows the example.

this would work:
books = new Book({id:options.name}, {url: options.name));

decodeURIComponent() will decode http://host/path/search%2Flife to http://host/path/search/life.

How can I turn the ember-data record into a basic query dict instead of JSON?

I've been able to hack around the ember-data RESTAdapter and make it work for my django web app using the djangorestframework. It's clearly a different flavor of REST from what Rails has implemented.
I'm extending the original DS.RESTAdapter to work with the django approach and I'm curious how I can take the "record" that they typically turn into JSON and instead make a basic query dict of "foo=bar&baz="
Here is what i've done so far that does work -I'd just like a less hard coded approach
DS.RESTAdapter = DS.Adapter.extend({
bulkCommit: false,
createRecord: function(store, type, record) {
var root = this.rootForType(type);
//var data = {};
//data[root] = record.toJSON();
var data = 'username=%#'.fmt(record.get('username'))
...

If you define your models like so:
MyApp.MyModel = DS.Model.extend({
property: DS.attr('string'),
....
});
MyApp.MyModel.reopenClass({
url: '/path?ids=%#
});
Then in your adapter:
find: function(store, type, id) {
var url = type.url;
url = url.fmt(id);
....
})

backbone.js change url parameter of a Model and fetch does not update data fetched

I have the following Model:
window.MyModel = Backbone.Model.extend({
initialize: function(props){
this.url = props.url;
}
parse: function(){
// #override- parsing data fetched from URL
}
});
// instantiate
var mod = new MyModel({url: 'some/url/here'});
I use this global variable 'mod' to fetch some data into this model from backend.
// fetch
mod.fetch({
success: function(){ ...},
error: ...
});
All above works well....
My Issue: I want to reuse this model by changing resetting the url and call fetch but it does not update the url somehow. I have tried the following:
mod.fetch({
data: {url:'/some/other/url'},
postData: true,
success: function(){ //process data},
error: ...
});
mod.set({url: '/some/other/url'});
// called fetch() without data: and postData: attributes as mentioned in previous
How do I set the url for my model so that I could call fetch() and it fetches data from updated url? Am I missing something. Thanks for any pointers..
UPDATE 1: Basically, I am unable to get updated values if I did
model.set({url: 'new value'});
followed by
model.fetch();
'model' is a global variable. Creating a fresh instance of 'model' works:
model = new Model({url:'/some/other/url'});
model.fetch();
however, works as required. Does this mean that a model instance is permanently attached to a url and it cannot be reset?
ANSWER TO MY QUESTION in UPDATE 1 Model instance is not permanently attached to a url. It can be reset dynamically. Please read through #tkone's thorough explanation and then #fguillens' solution for a better understanding.

After have understood the #tkone 's explanation...
If you still want to have a dynamic Model.url you always can delay its construction to run time, try this:
window.MyModel = Backbone.Model.extend({
url: function(){
return this.instanceUrl;
},
initialize: function(props){
this.instanceUrl = props.url;
}
}

Well the answer here is that you want to do:
mod.url = '/some/other/url'
The URL isn't part of the instance of the model itself, but rather an attribute of the MyModel object that you're creating your model instance from. Therefore, you'd just set it like it was an normal JavaScript object property. set is used only when the data you're setting (or conversely getting with get) is actually an attribute of the data you want to send/receive from the server.
But why you're changing the URL is the question we should be asking. The idea behind Backbone's model/collection system is that you speak to a REST endpoint and each model has a corresponding endpoint.
Like you've got a blog and that blog has an "entry" object which is available at:
/rest/entry/
And you've got a Backbone model for Entry:
Entry = Backbone.Model.extend({urlBase: '/rest/entry'});
Now when you save or fetch Backbone knows how this works.
So like you're making a new model:
e = new Entry();
e.set({title: "my blog rulez", body: "this is the best blog evar!!!!1!!"});
e.save();
This would then make Backbone do an HTTP POST request to /rest/entry with the body:
{
"title": "my blog rulez",
"body": "this is the best blog evar!!!!1!!"
}
(When you do your mod.set({url: '/some/other/url'}); you're actually adding a field called url to the dataset, so the server would send "url": "/some/other/url" as part of that JSON POST body above:
{
"title": "my blog rulez",
"body": "this is the best blog evar!!!!1!!",
"url": "/some/other/url"
}
The server would then respond with an HTTP 200 (or 201) response with the same model, only with, like, say, and ID attached:
{
"id": 1,
"title": "my blog rulez",
"body": "this is the best blog evar!!!!1!!"
}
And that's not what you're looking for, right?)
Now you've got this model and it's got an ID. This means if you change it:
e.set('title', 'my blog is actually just ok');
e.save()
Backbone now makes an HTTP PUT request on /rest/entry/1 to update the resource on the server.
The server sees that you're talking about ID 1 on the /rest/entry/ endpoint, so knows to update an existing record (and send back an HTTP 200).
TL;DR
Don't change the URL, Backbone will. Make a new model for a new piece of data.

model.urlRoot = "/your/url"
OR
model.urlRoot = function(){ return "/your/url"; }
OR
model.url = "/your/url"
OR
model.url = function(){ return "/your/url"; }
Default 'url' property of a Backbone.Model object is as below. Backbone.js doc says:
Default URL for the model's representation on the server -- if you're using Backbone's restful methods, override this to change the endpoint that will be called.
url: function() {
var base = getValue(this, 'urlRoot') || getValue(this.collection, 'url') || urlError();
if (this.isNew()) return base;
return base + (base.charAt(base.length - 1) == '/' ? '' : '/') + encodeURIComponent(this.id);
},
Clearly, It first gets the value of urlRoot, if not available, it will look at the url of the collection to which model belongs. By defining urlRoot instead of url has an advantage of falling back to collection url in case urlRoot is null.

You can set url as option in fetch function, like this:
var mod = new MyModel();
mod.fetch({
url: '/some/other/url',
data: {}
});

Backbone.js: bind data to Collection using Ajax?

I've just started using Backbone.js. I want to create a Collection and add some data from an external source.
The data is actually currently in CSV, not JSON, but I could re-render it in JSON if that is going to be a lot easier.
So, two questions:
Where do I bind external data to the Collection? It complains if I don't specify a url property, but I don't really have a URL in mind - I was planning to bind data via Ajax.
Should I re-render my data in JSON, rather than CSV, and use the Collection's url property to load it?
I just tried loading data directly into the Collection, rather than via the url property:
var Cat = Backbone.Model.extend({});
var CatCollection = Backbone.Collection.extend({
model: Cat
});
var ajaxData = { 'breed' : 'persian' } // simple example of external data
var catCollection = new CatCollection(ajaxData);
catCollection.fetch();
But this gives an error: Uncaught Error: A "url" property or function must be specified.

Either initialize/reset your collection with an array created elsewhere without using the fetch method for your collection
var ajaxData = [{ 'breed' : 'persian' }]; // Backbone.Collection expects an array
var catCollection = new CatCollection(ajaxData);
// catCollection.fetch(); fetch will try to update the data from the server
or use the built-in url/parse to build your models
var CatCollection = Backbone.Collection.extend({
model: Cat,
url: "your ajax source",
parse: function (csv) {
//convert your csv in an array of objects
return csvtoarray;
},
fetch: function (options) {
options = options || {};
options.dataType = "text";
return Backbone.Collection.prototype.fetch.call(this, options);
}
});
var catCollection = new CatCollection();
catCollection.fetch();
Converting your data server-side to JSON will probably be easier than trying to write a CSV parser in JS.