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returned object is undefined in a custom ajax service

I created an AngularJS service which does ajax request to the server and returns the response object to the controller. Below is my service
app.factory('ajaxService', function() {
return {
ajaxcall: function(url, type, data, handler) {
$.ajax({
url: url,
type: type,
data: data,
beforeSend: function(xhr) {
xhr.setRequestHeader("X-OCTOBER-REQUEST-HANDLER", handler);
xhr.setRequestHeader("X-Requested-With", "XMLHttpRequest");
}
})
.done(function(response) {
console.log("ajaxService done: ");
console.log(response);
return response;
})
.fail(function(response) {
console.log("in onCheckUser-error: ajaxService ");
});
}
}
});
The controller is defined as below
var app = angular.module('starter', [])
app.controller('myCtrl', function(ajaxService) {
var res = {};
res = ajaxService.ajaxcall("https://www.travelmg.in/check-login",'POST','',"onCheckLogin");
console.log(res);
});
Here, i get the expected response in console in the ajaxService service. When i return the response, i see an "undefined" value in res variable in console.
I don't understand why the res variable is undefined. Please suggest

Thats because your making an asynchronous call, which means it will not return the result immediately.
only way to resolve this is to receive the promise object returned from $.ajax & use the .done() function on it to receive the successful data.
What you need to do:
Move the done() & fail() outside service factory.
return the ajax promise object all the way to the consumer, i.e controller.
JS CODE:
//service factory code
return {
ajaxcall: function(url, type, data, handler) {
return $.ajax({
url: url,
type: type,
data: data,
beforeSend: function(xhr) {
xhr.setRequestHeader("X-OCTOBER-REQUEST-HANDLER", handler);
xhr.setRequestHeader("X-Requested-With", "XMLHttpRequest");
}
});
}
}
//controller code
app.controller('myCtrl', function(ajaxService) {
var res = {};
ajaxService.ajaxcall("https://www.travelmg.in/check- login",'POST','',"onCheckLogin")
.done(function(response) {
console.log("ajaxService done: ");
console.log(response);
//return response; // dont return instead process the result here
})
.fail(function(response) {
console.log("in onCheckUser-error: ajaxService ");
});
});
Note:
I would personally dont prefer mixing jquery and angularjs library unless jquery is really needed for some third party library. both are two different frameworks with different ideology,so dont mix them.
also if your referring to jquery only for $.ajax api ? then i would suggest you to use $http, whose API is same as $.ajax. ref: https://docs.angularjs.org/api/ng/service/$http

You have built the application in angular so it would be convenient to use $http directive to make ajax calls. Inject $http is your service, then you can handle the response as such:
ajaxService.ajaxcall("https://www.travelmg.in/check-login",'POST','',"onCheckLogin").then(function(response) {
console.log(response.data);
});

Backbone JSONP call from RESTful json API not working

I have a RESTful json API, which I need to access in my front-end Backbone site.
So, I did this:
/* Goal collection */
var GoalCollection = Backbone.Collection.extend({
model: GoalModel,
url: "http://staging.api.hiwarren.com:8080/api/v1/goals/?callback=?",
sync: function(method, collection, options) {
options.dataType = "jsonp";
// options.timeout = 10000;
return Backbone.sync(method, collection, options);
},
parse: function(response) {
return response.results;
}
});
/* View for the goal collection */
var GoalCollectionView = Backbone.View.extend({
tagName: 'ul',
initialize: function(callback){
var that = this;
_.bindAll(this, 'render');
that.collection = new GoalCollection();
that.collection.bind('reset', this.render)
that.collection.fetch({
dataType: 'jsonp',
success: function(collection, response){
that.render();
if(callback) callback(that);
},
error: function(collection, response){
throw new Error("Goal fetch error - " + response.statusText);
}
});
},
render: function(){
this.collection.each(function(goal){
var goalView = new GoalView({ model: goal });
this.$el.append(goalView.render().el);
}, this);
return this;
}
});
I am trying to use JSONP, because it is a different domain. I've followed answers to questions similar to this, as you can see in my code, but it doesn't work.
Instead, I get this error message:
Uncaught Error: Goal fetch error - load
Backbone.View.extend.initialize.that.collection.fetch.error
options.errorjquery.js:3094 jQuery.Callbacks.fire
jQuery.Callbacks.self.fireWithjquery.js:8261 done
jQuery.ajaxTransport.send.jQuery.prop.on.callback
jQuery.event.dispatchjquery.js:4116 jQuery.event.add.elemData.handle
What am I doing wrong? How can I make this work?

Are you sure that the domain you are trying to access has support for jsonp? Some sites only enable the json format.

using backbone with third party api

I'm trying to use backbone to grab hold of an instagram feed. This doesn't require authenticating the user, it is pulling a public feed available through:
https://api.instagram.com/v1/users/<user_id>/media/recent/?client_id=<client_id>
I've gotten as far as outputting the JSON response into the console, but I'm unable to make it display on my page.
In the code below, I use fetchData to grab the feed, and I'd like to eventually get it to a point where render outputs everything stylized on #social. However, despite setting the feed property to the JSON response, render still returns an empty object. console.log in fetchData however displays the proper information.
var social = {}
social.Instagram = Backbone.Model.extend();
social.InstagramFeed = Backbone.Collection.extend({
model: social.Instagram,
url: 'https://api.instagram.com/v1/users/<user_id>/media/recent/?client_id=<client_id>',
parse: function(response) {
return response.results;
},
sync: function(method, model, options) {
var params = _.extend({
type: 'GET',
dataType: 'jsonp',
url: this.url,
processData: false
}, options);
return $.ajax(params);
}
});
social.InstagramView = Backbone.View.extend({
el: '#social',
feed: {},
initialize: function() {
this.collection = new social.InstagramFeed();
this.fetchData();
this.render();
},
render: function() {
console.log(this.feed);
},
fetchData: function() {
this.collection.fetch({
success: function(collection, response) {
// console.log(response);
feed = response;
// console.log(this.feed);
},
error: function() {
console.log("failed to find instagram feed...");
}
});
}
});
social.instagramview = new social.InstagramView;
I've tried to output the information using just the fetchData function however this.el.append(response) results in a notice saying that el is undefined.

Your render method is called before the fetching has completed. You should bind to the sync event of the collection and call render in the event handler.
social.InstagramView = Backbone.View.extend({
el: '#social',
feed: {},
initialize: function() {
this.collection = new social.InstagramFeed();
this.fetchData();
this.collection.on('sync', function(){
this.render();
}, this);
// this.render();
},
...
})
Quoting Backbone.js documentation : sync event is fired :
when a model or collection has been successfully synced with the server.

Get values from object using Backbonejs

i want to get value from this API http://demo82.com/lois/api/get_page/?id=6 using Backbone js. i tried but i don't know how can we get values from object in backbone.
here is my Backbone code
Page = Backbone.Model.extend({
initialize: function() {
this.on('all', function() { console.log(this.get('page')); });
},
url: "http://demo82.com/lois/api/get_page/?id=6",
defaults: {
"id":null,
"title":"",
"content":""
}
});
var page = new Page();
console.log(page.fetch({}));
i am new and try to learn backbonejs please explain what is the better way ? please give me ans using jsfiddle.net.
thanks

Is id always going to be 6? In your code, your model is always getting the 6th thing. If you want a custom url with a get parameter, override url as a function:
url: function() {
id = this.get("id");
return "loispage/api/get_page/?id=" + id
}
Better yet, if you have control over the server side and can do something a little more RESTful with a page entity -- simply set urlRoot
urlRoot: "loispage/api/page/"
and fetch will automatically do an HTTP get from
"http://.../loispage/api/page/<id>

It looks like a context problem (this doesn't refer to the model in on's callback). You can fix this by specifying the context:
this.on('all',
function() { console.log(this.get('pagel')); },
this
);
Edit
There's also a cross-domain issue. You'll need to use a JSONP request for this by overriding sync and parse. (I adapted the following code from this example.)
var Page= Backbone.Model.extend({
// override backbone synch to force a jsonp call
sync: function(method, model, options) {
// Default JSON-request options.
var params = _.extend({
type: 'GET',
dataType: 'jsonp',
url: model.url(),
processData: false
}, options);
// Make the request.
return $.ajax(params);
},
parse: function(response) {
// parse can be invoked for fetch and save, in case of save it can be undefined so check before using
if (response) {
console.log(JSON.stringify(response));
// here you write code to parse the model data returned and return it as a js object
// of attributeName: attributeValue
return { status: response.status }; // just an example
}
},
Here's a JSFiddle demo.

Backbone.js fetch callback

I'm using Backbone.js and using fetch with options, but it doesn't seem to get the error or success callbacks, however data is being returned.
this.user.fetch({data: {username : this.username.val(), check : 'true'}}, {
error: function(model, response) {
console.log(response);
},
success: function(model, response) {
console.log(response);
}
});
This is what I have setup, am I missing something? It never hits error or success, but it does do the ajax request and it's returning data.
Thank you!

You're passing 2 separate arguments to fetch. Combine them into a single object with data, success, and error fields and it should work for you.

Example for x1a4 answer
var myModel = new MyModel({id: modelId});
myModel.fetch({
success: function (model) {
console.log('success: model fetched');
},
error: function () {
console.log('error: loading model');
}
});