Handle ajax Requests in Angular JS - angularjs

I am working on one web application which is Single Page Application.
In that my front end will be on server and back end will be on other server.
So for each add/edit/delete/fetch operation , i need to call an Ajax request to the Back End.
There are plenty of ajax requests till now.So is there any way to handle them. I mean in angular js is there any way to do so?
FYI. I am bit new in the Angular Js.
Thanks.

You can create factories using ngResource https://docs.angularjs.org/api/ngResource or individually using make individual requests using $http service provider https://docs.angularjs.org/api/ng/service/$http. I would recommend to go for factories method. You will find this link useful if you are looking for ward to experiment it https://www.sitepoint.com/creating-crud-app-minutes-angulars-resource/

Related

best practice to pass mock data to Angular & Ionic

I am working on an Ionic phone app using AngualrJs as the framework. Now I faced an issue. I don't want my app to send an HTTP request to my backend(which use Ruby on Rails) API to do a manual test.
So I'm wondering what's the best practice to pass a mock JSON data as a response when I want to call the API.
I'm not familiar with Angular and Ionic, I can find some tutorials on both sides but I don't know what's is the best practice if use them together.
You can either store the data in localStorage after the first hit and read the data from localStorage every-time whenever you need.
https://medium.com/#petehouston/awesome-local-storage-for-ionic-with-ngstorage-c11c0284d658
Or you can use
$httpBackend
https://docs.angularjs.org/api/ngMock/service/$httpBackend
by saving json files locally and injecting them back when the application tries to hit the network . One limitation here, you cannot update the json file later after the user have installed the application.
So, localStorage is preferred if you want to cache the data you have received from network.

Asp.Net MVC and AngularJS in same View

I´d like to know if exists a better way to render a view like this:
For the first load I need bring data from Controller like usual but after apply a filter in same page I need to start use AngularJS and never more uses Razor.
Is there a way to do that ?
Thanks for all.
Yes. you can do that.
Basically, you'd need to add the line below in your view. After you do that, the json is going to be available to the DOM / javascript and angular can take it from there. Hope this help
var json = '#Html.Raw(Model.MyJsonStringForMyCoolAngularJsApp)';
There are multiple ways to implement ASP.Net MVC with AngularJs.
I personally like Mini SPA (Silos). You can watch Miguel A Castro's video here.
You can also download the source at his website.
What it does is when a request comes in, it goes to ASP.Net MVC Route first. Then, Angular Route takes over the rest. It is a very slick design.
FYI: I also use Angular.Net Helpers to generate strongly typed views.
You could use WebAPI project in visual studio to exchange data between frontend and backend. It would go stateless, so to secure the data, you could use a mechanism like JWT.
The frontend would exchange JSONS from/to the backend using REST apis.
Yes. You can make angular views and exchange data using $http.get(/controller/method/). You can also configure routing using ngRoute.

How can I update the $scope in AngularJS when a server sided update occurs?

Background
I am trying to make a single page real-time application that uses a PHP , MYSQL back end and AngularJS frontend
My back end is using CakePHP framework which serves a JSON API and the front uses ngResource in AngularJS to access this API.
I have got 'Ratchet WebSockets for PHP' working, which can trigger a response to the browser via websockets when something updates in the back end.
My Incomplete Solutions
Solution 1: Use the response via the websocket to update the AngularJS $scope object through some kind of $scope.model.push(websocket.data) method?
Solution 2: Use the response via the websocket to trigger Refresh on the ngResource which would refresh the $scope object completely?
Question
Are my solutions viable? and how could I achieve it ?
You just need to read events from the WS and populate them using $emit and $broadcast, then your controllers can subscribe to whichever events are relevant to them.
Take a look at:
angular websocket factory
AngularJS and WebSockets beyond

Using Angular with Play: Role for Scala Templates?

When I first looked at Play and went through all the samples, I was pretty excited by the zentasks sample and the fluid, clean, effortless Javascript routing that left the work of rendering things to Play. But we decided instead to go with Angular.
Upon going down that road, I thought that Angular would control all aspects of rendering.
However, we have a page that has to get a socket. We were having the socket made on the server, so for now, we still have a Play (Scala) template doing that. We have pared it down to pretty much nothing: create the socket and then inject it into the Angular context.
But we are also trying to do Protractor tests and that is made uglier by having to figure out how to accommodate the Scala template.
Question: should we just ditch the scala template and have the Angular controller call the server and get the socket? That was my favored approach to begin with.
I'm currently working on two Play apps with Angular and in both we decided to have one single main.scala.html file that load all the necessary controllers,services,directives, etc from angular using of require.js.
The goal with Angular is to create a single page app and therefore you should avoid to mix it with server side templates.
You must see your main.scala.html template as the entry point of your single page application. There you generate and load all the pieces you need and give the hand to angular to manage the rest.
I agree with Renato. It's probably better to have a single controller and template that sets up the single page app with angular. Then use AJAX to send requests from the browser to other controllers (see http://www.playframework.com/documentation/2.2.x/JavaJsonRequests).
If want to to avoid Scala templates completely, you can put your web pages and javascript in the public directory and only use AJAX.

AngularJS getting data from backend

I would like to know what is the proper way to get data from backend when I want to use angularJs (or similar) in my web app?
The only way I see is to render html (static html with js scripts - e.g. angularjs) with no data from backend and then download data via ajax requests from my backend API. But I think this solution is not good because of many HTTP requests:
For example I have blog website, I want to show a post, comments, and the related posts on the sidebar. So probably I need to make at least 3 HTTP requests to get the data unless I will prepare API to get all I need in one request.
I can also imagine websites that could have much more HTTP requests. Is it a proper way to do this? Doesn't it overload a server? Or my way of thinking is so wrong?
It is either websockets or HTTP requests. Preparing API to get all in one request is one option. Another two options are XMLHttpRequest/iframe streaming which is a method of a technique known as Comet.
I would go with websockets since it is supposed to solve the problem that was previously solved with weird applications like iframe streaming. There are libraries that properly handles fallbacks if the browser does not support websockets:
web-socket-js ( this needs a websocket server )
Socket.IO ( this has a node.js module and also implements a kind of unnecessary protocol on top of websocket protocol )
If you choose the old methods there will be many problems waiting for you on the road like XmlHttpRequest.responseText while loading (readyState==3) in Chrome
I think you have to distinguish two cases:
You render the page for the first time.
You update parts of your page when something changes
Of course in the second case it makes sense to fetch only parts of the page via individual HTTP requests. However, in the first case you can simply serialize your complete model as one JSON object and embed it in the page like this:
<script type="text/javascript">
var myCompleteModel = { /* Here goes your model */ };
<script>
The controllers of the components on your page can then access this global variable to extract the parts being relevant for them. You can also wrap access to the initial model in a service to avoid accessing a global variable in all your controllers.

Resources