I'm trying to send an object from Backbone.js to my Rails backend. Currently when I call save() on my model, it sends this to the server:
{"program_id":1,"issuer_id":4}
But Rails is expecting it in the following format:
{"program_issuer_link":{"program_id":1,"issuer_id":4}}
Is there any way I can do this encapsulation to the JSON object that gets sent from Backbone.js to Rails when I call save() on my model? I've looked through the documentation but couldn't find anything about it.
if you are using the backbone-rails gem, then you can do it like this.
var User = Backbone.Model.extend({
paramRoot: 'user'
});
You can also override the toJSON method like this
var User = Backbone.Model.extend({
toJSON: function(){
return {user: _.clone(this.attributes)}
},
});
Related
I need to make a POST to a server-side API. I must send an id key into the request body to the server.
I use a Backbone model. But when I do:
myModel.set("id", somevalue)
myModel.save()
The network request that is fired is : URL/someValue [PUT]
Backbones doesn't do a POST but a PUT and appends the id to the url.
So I just want to pass an id key to the server without Backbone noticing.
From Backbone's doc:
Backbone is pre-configured to sync with a RESTful API.
[...]
The default sync handler maps CRUD to REST like so:
create → POST /collection
read → GET /collection[/id]
update → PUT /collection/id
patch → PATCH /collection/id
delete → DELETE /collection/id
A new entry doesn't have an ID, so if you give an ID to the model before saving it, Backbone defaults to a PUT request because it thinks you want to save an existing entry.
How to make a POST request with an id?
Choose one of the following solutions.
Stick to a RESTful API
This one is the obvious one. If you can, stick to the standard.
Change the API to handle PUT/PATCH requests and only use POST on creation. Make the API endpoint take the ID from the URL.
RESTful API best practices
Pass the type option1
Simple and works really well for a one-off situation.
Every options passed to save (or fetch) overrides the options the sync function defines by default and passes to jQuery.ajax function.
Backbone sync source
// Make the request, allowing the user to override any Ajax options.
var xhr = options.xhr = Backbone.ajax(_.extend(params, options));
var url = model.url(); // get the url before setting the `id`
model.save({
id: somevalue
}, {
url: url, // fix the url
type: 'POST' // choose the HTTP verb
});
Fixing the url that the model uses is simple, you have also some choices:
pass the url option (like above)
override the url function of the model
Overriding the url function (source) works well for situation where every call should use a specific url, without the default id appended to it.
var MyModel = Backbone.Model.extend({
url: function() {
return _.result(this, 'urlRoot') ||
_.result(this.collection, 'url') ||
urlError();
}
});
Set the idAttribute on the model
This depends on what the id you're trying to pass means in the data.
Backbone Model uses "id" has the default id attribute name. You can specify a different name by overriding the idAttribute property of the model. Whatever the name, it is always automatically made available through the model.id property.
Now, assuming the id attribute isn't related to this model and this model's real id attribute name is something like UID, you could change the idAttribute of the model to reflect the real name of the attribute (or it could even be a string that's never going to be an attribute).
var MyModel = Backbone.Model.extend({
idAttribute: 'UID',
});
Now, the id attribute is not considered an id for the current model, and model.isNew() will return true, sending a POST request to create it on save.
Change the sync/save function behavior
If the API you're using is not RESTful, you can adjust the behaviors by overriding the sync function. This can be done on the model or collection, or on the Backbone.sync function which is used by default by the collections and models.
For example, if you wanted to make every request use POST by default for MyModel class:
var MyModel = Backbone.Model.extend({
sync: function(method, model, options) {
return Backbone.sync.call(this, method, model,
_.extend({ type: 'POST' }, options));
}
});
You could do something similar with only the save function to let the fetch do its GET request as usual.
Use the emulateHTTP setting2
If you want to work with a legacy web server that doesn't support
Backbone's default REST/HTTP approach, you may choose to turn on
Backbone.emulateHTTP. Setting this option will fake PUT, PATCH and
DELETE requests with a HTTP POST, setting the X-HTTP-Method-Override
header with the true method.
[...]
Backbone.emulateHTTP = true;
model.save(); // POST to "/collection/id", with "_method=PUT" + header.
Do not override isNew
Has this model been saved to the server yet? If the model does not yet
have an id, it is considered to be new.
Some other answers on this site suggest overriding the isNew function. Don't. The function has its purpose and overriding it to force a POST request is a poor hack, not a solution.
isNew is used internally but can also be used by your code or other libraries and Backbone plugins.
1 While I did not take this from stack overflow, it was already an answer by Andrés Torres Marroquín on a similar question.
2 Taken from Maanas Royy's answer.
Disclaimer: I'm a WebApi/BackBone beginner, so the question might be a bit odd since there is a lot about these components I don't really know and/or understand.
It would be nice to have the possibility to issue just ONE sync() call to the server to synchronize everything. I mean, when I saw sync() method, at first I thought it's used like that, but as soon as I saw the "create", "update", "delete" params I realized it's not. But there is an underlying problem related to Backbones default implementation for DELETE.
I've learned that classic implementation of Backbone.js allows one deleted (destroyed) model at a time to be sync'ed to the server. Created/modified (POST/PUT operations) content is sent in the request body itself, so the JSON is filled with the data and deserialized by WebApi model binding on the server. It doesn't work like that for DELETE, since body is always empty and reference to the model is made by URL parameters in query string. So, I guess to achieve that functionality, the request for DELETE should be sent in body as well as for POST/PUT.
Is there a possibility to change all of this behavior AND make it work with WebApi? I googled for that stuff already, but can't find anything to point me to the right direction.
What I have until now is a Backbone model, collection and a view set up.
Backbone.sync("create", this.collection); is called by the view on button click.
On the server side there is a WebApi controller set up with scaffolded methods:
// GET
public IEnumerable<Ponuda> Get()
{
return _storageService.GetPonude().ToList();
}
// GET
public Ponuda Get(int id)
{
return (Ponuda)_storageService.GetPonuda(id);
}
// POST
public void Post([FromBody]IEnumerable<Ponuda> value)
{
_storageService.CreatePonude(value);
}
// PUT
public void Put([FromBody]IEnumerable<Ponuda> value)
{
_storageService.ModifyPonude(value);
}
// DELETE
public void Delete(IEnumerable<int> value)
{
_storageService.RemovePonude(value);
}
EDIT: I'm reading about Marionette.js and it seems to offer standard model/view related functionalities out of the box. However, I still can't see the possibility to save/sync e.g. the entire modified collection at once.
To sync all contents at once :
For POST and PUT Http methods, you can use Backbone.Sync API.
For DELETE, you can directly use the ajax API for deleting the content in the server and use Backbone Collection remove API to delete the content in the client side.
I have written skeleton code which demonstrates on how to achieve the functionality:
var PersonModel = Backbone.Model.extend({
url: '/demo',
defaults: {
"id": 0,
"name": "",
"age": 0
}
});
var PersonCollection = Backbone.Collection.extend({
url: '/demo',
model: PersonModel
});
var model1 = new PersonModel({"name": "John", "age": 30});
var model2 = new PersonModel({"name": "Joseph", "age": 30});
var collection = new PersonCollection();
// model will be added locally on client side. It will not sync to the server.
collection.add(model1);
collection.add(model2);
// POST. This will create both the models together using a single REST API request.
Backbone.sync('create', collection);
// PUT. This will update both the models together using a single REST API request.
Backbone.sync('update', collection);
// Extract the model ids to be deleted
var modelIds = [model1.get('id'), model2.get('id')];
$.ajax({
method: 'DELETE',
url: '/demo',
data: JSON.stringify(modelIds), // This will add ids to the request body
contentType: 'application/json',
success: function() {
// On successful deletion on server end, delete the models locally.
collection.remove([model1, model2]);
}
});
Regarding the WebApi, since I have not worked on it, will not be able to guide you. Having worked on Spring Rest API, I can tell you above functionality should work with the WebApi.
I'm having an issue getting Ember.js with Ember Data to hit a nested resource API endpoint. Here is my code:
https://gist.github.com/feliksg/7470254
Here is what i'm using:
DEBUG: ------------------------------- ember.js:3224
DEBUG: Ember : 1.2.0-beta.3 ember.js:3224
DEBUG: Ember Data : 1.0.0-beta.2 ember.js:3224
DEBUG: Handlebars : 1.0.0 ember.js:3224
DEBUG: jQuery : 2.0.3 ember.js:3224
DEBUG: -------------------------------
I'm also using Ember Appkit as the base for this project.
Basically the issue is when I try to submit a new post, ember data does the following:
POST request to /user/posts
instead of a
POST request to /users/1/posts
In addition, for some reason the request payload as shown by chrome inspector shows the form data being passed to the API looks like this:
{ "user/post": { "published":false, "created_at":null, "user":"1" } }
However, I would expect the data to be passed in like this:
{"post": { "body":"some text...", "published":false, "created_at":null, "user_id":"1" } }
So for some reason, it doesn't even pass in the 'body' field even though I have it in the form.
Any help is greatly appreciated!
UPDATE 1
When I visit http://localhost:8000/#/users/1/posts, it sends a GET API request to /users.json. There must be something wrong with the way I set up the PostsRoute but i'm not sure how to fix it.
UPDATE 2
I've updated my PostsRoute to fetch the JSON without using Ember Data which returns the records, but now the posts template does not render. My PostsRoute now looks like this:
PostsRoute = Ember.Route.extend
model: (params) ->
user = #modelFor('user')
userId = user.get('id')
return $.getJSON('http://localhost:5000/api/v1/users/' + userId + '/posts.json')
I also get the following error:
Error while loading route: TypeError: Object # has no method 'slice'
So when you create/use 'users/post' you are defining a namespace where the post lives, not that it's underneath a specific model. AKA, it isn't going to use the associated user model to build up your url, it's just going to make requests using users as part of the post.
I'm not totally positive why the body isn't being attached to the post, are you sure the model includes the body? Are you sure the body property exists on the model you are sending into the createRecord?
BTW, needs doesn't do anything on a route, it only applies to controllers.
The tutorials & guides that I've found suggest that Ember.js models are very data centric, in that you have data in the browser that is persisted to the server and/or a model is filled with data from the server.
How about something that is more verb centric? For example, my case is that, so far, I have a "Search" model, where a search has a query, a state ("beforesearch","duringsearch", etc...), and, hopefully, some results. I want for the search to then "runQuery", which fires off an ajax request to the server, which returns and fills the model with the results, and changes its state to "aftersearch".
What's the best way of handling such verbs on models? Should the "runQuery" go via ember-data, or just manually fired off using $.ajax or similar? Am I maybe thinking about models in the wrong way, and this should actually go via a controller?
Edit: After reading up a bit on REST, I think what I'm wanting is to POST to a "controller" resource. So, for example:
POST: /searches (to create a search)
POST: /searches/1/run (to execute search 1's "run" controller
Does Ember.js / ember-data have a recommended way of calling controller resources like this?
Ember-data is very oriented around using model objects that contain various information fields and relationships and are defined by a unique id. Half of my API is like what ember-data expects and half is like you described, it is more about data processing or performing a calculation than creating/retrieving/updating/deleting a data object that has an id. It doesn't make sense to treat these calculations the same and assign it an id and persist it in the database.
In my case, since I have both ember-data style data objects and calculation functionality I use a mix of ember-data and custom ajax requests. I have relational data stored that is retrieved by ember-data but I augment the models to include access to the calculation portions.
For example:
App.Event = DS.Model.extend({
name: DS.attr('string'),
items: DS.hasMany('App.Item'),
...etc...
searchData: null,
searchInEvent: function(data) {
var _this = this;
return $.ajax({
url: "/api/events/" + this.get('id') + "/search/",
dataType: 'json',
type: 'POST',
data: data
}).then(function(result){
_this.set('searchData', result);
});
}
});
App.Event is a normal ember-data model and is loaded by the router through the usual ember conventions, and as the various controllers need access to the search functionality they can access it through searchInEvent and searchData that were added to the model.
Here is a collection I define in backbone.js
var List=Backbone.Collection.extend({
model: Item,
url: "TodoApp/index.php/todo"
});
var list=new List
Then I created a Model in the collection with an ID=80
Now, when I do list.fetch();
It will make a call to
"TodoApp/index.php/todo/80"
However, at the backend, using Codeigniter, I really need to have
TodoApp/index.php/todo/get/82.........where get is a function I defined to access DB
So, should I change the Collection url to "TodoApp/index.php/todo/get"
But again, that's not really where the resource is located?
In route.php try:
$route['todo/(:num)'] = "todo/get/$1";
HERE is what I ended up doing.
I renamed the index of the controller to resource
therefore using a URL of:
TodoApp/index.php/todo/resource
When getting a GET request at
TodoApp/index.php/todo/resource/80
extract the second segment of the URI and read from DB with that.