Silverlight with mvc or Ria Services? - asp.net-mvc

I have an Asp.net MVC application which uses html5 and jquery on the client side. Management want to experiment with Silverlight as they feel it will give the end user the impression they are running a desktop application rather than web based application.
What I want is to create a silverlight version of the application but unlike a MVC application where html views are returned I really want to have data just returned and consumed by the silverlight application. So each time I go to a new page in the silverlight application only the data is returned to populate it (I do not want to return a xaml page which has the data embedded in it). So all my application logic will be in the silverlight application.
Since our application will be a multi-user system, one of the requirements is that when showing a grid of data in the silverlight application the grid must be periodically updated as other users add and remove records. Currently with the MVC app I have a timer which updates the grid with an Ajax call every few seconds.
I am not sure if I can reuse the mvc controllers and actions and just return data or whether I should go with RIA services as it may provide me with other richer functionality.
JD

RIA does provide with richer functionality, but IMO lacks the very reusability (interop with jquery for example) you'd need here. See Tim Heuer's blog on how to use Silverlight as a View with MVC here, and maybe add an extra parameter to your call's like (?mode=sl) and check for it in your controllers, so gather all your data you'll need for your views then
if (mode == "sl") return Json(data);
else return View(data);
Of course, life is not this simple, you'll have problems with Child Actions, ViewModels, etc. But it's a start.
On the other hand if you're just doing CRUD operations, and have written almost no business logic into your controllers, then fire away with RIA! IMO, the most important thing of them all is DRY!!! (Don't repeat yourself) So if you have lot's of code in Controller then don't rewrite it around RIA in SL again!

Both? :)
Create one or more repositories to contain your data IO and business logic and let your MVC actions and domain service methods surface what's needed.

Related

Routing: in AngularJS or .NET MVC?

We are starting a major upgrade of a large WebForms application. The logic will be split between AngularJS on the front end and .NET MVC on the back end. What are the criteria about where to put routing? I can put it in RouteConfig.cs on the server and have .NET to be responsible for routing; or I can use ng-route on the client, and use only WebApi calls to the server.
I see pros and cons both ways, and I was wondering if anybody has any decision criteria. Or some articles that I missed (Google has plenty on implementing the routes; but not on the decision to pick one over another).
I would argue for full separation of concerns, so routing on the client. Doing the routing on the client puts the client in control of what is being displayed. The server would only serve the raw data via rest.
This also allows you more flexibility in the future as well. Say in 2 year you want to ditch Angular for the next new client framework. All you need are client developers to implement the UI calling the existing endpoints, the server code would not need to be touched. Want to move away from .NET backend? No problem, just implement the endpoint in the new framework, not client could would need to be changed.
You should use both as your application is large.
let say your screens are divide on the bases of rule.
When Admin will login you will load all files related to that functionality and after that take benefit of ng-view and make that functionality as a single page app.
So in this way you don't need to load all files once. by ng-view you can also share data between different screens.

ASP.NET MVC and Angular JS tipping point

I want to create a largish ASP.NET MVC Web application. On some pages I would like to utilise AngularJS.
This app will not be a SPA.
At what point does this become a problem? For example at what point does running effectively two MVC paradigms become a headache?
Or is it a case of as long as you have clear delineation between what's using ASP.NET MVC (standard action methods etc) and what's using Angular JS then the two run side by side ok without giving you massive code organisation/maintainability headaches?
Cheers for any wisdom.
I'd love John Papas opinion!
Andrew
Since you are only asking for opinions, I will be happy to share my experience. The two do mix very well, and I think in most cases (at least most of my own development) the .NET side becomes very light weight.
Your .NET Web API Controller becomes a simple call to the Data Layer to populate a model or List(Of T) models. This gets returned as JSON to the Angular service.
From there, Angular takes over all of the logic until you need to perform another CRUD operation. Manipulating, validating, etc. all happens client-side in either the model (for me the Angular service acts as the model in MVVM) or the angular controller (which is really a ViewModel).
It's best if you let your model (Angular service) handle as much business logic as possible and restrict the Angular controller to responding to clicks, input controls, etc.
To sum up, let your .NET server side be very light. Just transport data back and forth to the Data Layer. Let Angular do the heavy lifting. You definitely do not need to be building a SPA to see the wonderful benefits of a JS data binding library, of which Angular is arguably the best of breed.
An excellent blog post that contains [ details of what I've discussed here ].
Good luck!
I use ASP.NET MVC alongside AngularJS for a fairly large in-house application. We don't really use many features of ASP.NET MVC beyond the basic page template and script bundling - so everything from the client-side is controlled by AngularJS and client-side routing - except for some distinctions we've made between 'modules' of the app where we wanted a different ng-app for each, along with different script dependencies.
If you're looking to take advantage of AngularJS on a page-by-page basis then I think you have no problem at all. As long as you reference the scripts (both core AngularJS scripts, and your AngularJS scripts for modules, controllers, etc.) correctly then you can just begin decorating elements with ng-app, ng-controller, etc. and it will just work. You could insert the relevant AngularJS scripts for relevant .cshtml pages using a #section declaration.
It will only be more complicated if you need a mix of server-side and client-side routing. Then it will be a case of carefully constructing ASP.NET MVC routes to deliver the SPA functionality where needed.

Is it a good practice to use an MVC application's own Web API for Ajax bindings?

I'm writting an application that has many Ajax widgets (Kendo-UI to be percise). It's starting to get messy to have all those Ajax responses without the standard controllers so I was starting to consider making each entities their own controller. If I'm taking the time to do this, I figured I might as well go foward and do those as WebAPIs since I was planning to do this in a not so close future, but hey, it would be done already...
So my question is: Is it a good practice to use an MVC application's own Web API as a Ajax Widget feeds or is there any reason to stick with standard Controllers?
I've seen some arguments about performance, but I don't think this applies to this situation. I believe it was more of a "Controller calling WebAPI" situation which has obvious performance hits. But since it's already a client side Ajax call, weither it goes into a standard MVC Controller or a WebAPI controller shouldn't change a thing, would it?
Edit
Additional information regarding the project:
I am using Entity Framework for the data access.
I have a repository pattern going on with UnitOfWork.
I am using proper a MVC structure (EF POCOs AutoMapped to DTO POCOs in the repository and fed into View Models by the controllers)
This is a MVC 4 project on .NET 4.0
There is a lot of database relationships (specially for the object I'm working with at the moment)
I don't know about "good practice", but it's certainly not "bad practice". I see no difference whether you do it in the app or a different one.
I think its a good thing but only if what you are doing in the API is kept as generic as possible to other applications and services can reuse the API.
Both the applications I have written and continue to maintain use pretty much the exact same stack as your app.
I have recently re-factored one of the applications to use the API for all the common things like lists that I'm binding to Kendo ComboBoxes etc. in my views. Its a fairly large application that re-uses a lot of the same lists such as states, priorities, complexities across various Entities and views so it makes sense to put those in the API.
I haven't gone as far as going the whole hog through. I draw the line with things like this:
public ActionResult GetAjaxProjectsList([DataSourceRequest]DataSourceRequest request)
{
return Json((DataSourceResult)GetProjectsList().ToDataSourceResult(request), JsonRequestBehavior.AllowGet);
}
That is very specific to how the Kendo Grid wants the data back. Nothing else I have connecting to this app will use this data in this format so I keep it in the controller.
In short... I use the API for common things within the same MVC app and things that I allow to be used by other applications or services, like Excel.

wcf and knockout.js combine

I got my datalayer, business layer ready. Now i want to to implement service layer.
I do not want to implement this layer in wcf ria services. Is there any other way to implement this layer in such a way using wcf, so that I get my model through wcf using js.
For example I have my domain 'Person'. (In domain project). Then in my 'PersonRespository' has
InsertPerson, GetPerson etc. to get and store the 'Person' in database.
Now I want to use asp.net mvc to show the person detais.
So next two layer will be Presentation Layer and service layer and manipulate data on client side using knockout.js and I am stuck on following issues.
Where will be mine Presentation layer will live. I am using asp.net mvc so It should be in model folder of mvc application, Is it wise to copy the same code class (Person) to model folder as well from domain model. Event when they are same.
How I will be able to get 'Person' model class in javascript and able to update it from javascript to database as well.
Is my architecture style is of enterprise level or i am missing something.
Any point to tutorial will be helpful.
If you have any further questions please let me know.
Thanks,
Daljit
Question 1:
No you should not be repeating your code. There is talk about this in the DRY (http://en.wikipedia.org/wiki/Don%27t_repeat_yourself) principals of development.
Question 2:
It is recommended that you serialize your model using a json serializer and send it to your UI. It will be updated etc, and then sent back to the services. Google MVVM pattern in javascript to see how this is done. KnockoutJs is a great start in achieving what you want. Its probably best to check out some examples done in knockoutjs to see what is going on. There are also many examples in MVVM for WPF that might help understanding the pattern at a higher level. I would recommend seeing codeproject.com for indepth MVVM examples.
As far as your layers go, you have many options, but a generic recommendation would be:
1) Presentation must be triggered through MVVM bindings, ie if the binding updates, the UI will then update itself.
2) the asp.net side of things should only update the models when sending updates via ajax to the UI. (not everything needs to be sent via ajax, im not saying that. When it does, it shouldn't also send extra html or js to put in the page).
3) Your models should really come from asp.net to the html page. (this will make things easier later, as the page will only be updated via asp.net models and you won't get items coming from multiple domains, which ends up being a nuisance.
4) Your asp.net site should provide a wrapper for your WCF service, and can foward calls to WCF.
OR
If you didn't want to wrap WCF with asp.net and needed your UI to communicate directly via ajax to WCF (should be a rarer usecase like doing an igoogle like page with widgets, or maybe mobile development with no asp.net interaction, ie full js app) Then you can investigate CORS as an option to go from JS to WCF and JS to asp.net (This is of a hard difficulty, easy to program, hard to get working for WCF as there is very very low documentation on it for in my case non IIS hosted WCF). See this page for information: http://enable-cors.org/

What Is ASP.Net MVC?

When I first heard about StackOverflow, and heard that it was being built in ASP.Net MVC, I was a little confused. I thought ASP.Net was always an example of an MVC architecture. You have the .aspx page that provides the view, the .aspx.vb page that provides the controller, and you can create another class to be the model. The process for using MVC in ASP.Net is described in this Microsoft article.
So my question is. What Does ASP.Net MVC provide that you wouldn't be able to do with regular ASP.Net (even as far back as ASP.Net 1.1)? It is just fancy URLs? Is it just for bragging rights for MS to be able to compare themselves with new technologies like Ruby On Rails, and say, "We can do that too"? Is there something more that ASP.Net MVC actually provides, rather than a couple extra templates in the File->New menu?
I'm probably sounding really skeptical and negative right now, so I'll just stop. But I really want to know what ASP.Net MVC actually provides. Also, if anybody can tell me why it's Model-View-Controller and not in order of the layers of View-Controller-Model or Model-Control-View depending on whether you are going top to bottom, or vice versa, I'd really appreciate that too.
EDIT
Also, it's probably worth pointing out that I've never really cared for the web forms (AKA server controls) model either. I've only used it minimally, and never on the job.
.aspx doesn't fulfill the MVC pattern because the aspx page (the 'view') is called before the code behind (the 'controller').
This means that the controller has a 'hard dependency' on the view, which is very much against MVC principles.
One of the core benefits of MVC is that it allows you to test your controller (which contains a lot of logic) without instantiating a real view. You simply can't do this in the .aspx world.
Testing the controller all by itself is much faster than having to instantiate an entire asp.net pipeline (application, request, response, view state, session state etc).
Scott Guthrie explained it in this post "ASP.NET MVC Framework"
It enables clean separation of concerns, testability, and TDD by
default. All core contracts within
the MVC framework are interface based
and easily mockable (it includes
interface based
IHttpRequest/IHttpResponse
intrinsics). You can unit test the
application without having to run the
Controllers within an ASP.NET process
(making unit testing fast). You can
use any unit testing framework you
want to-do this testing (including
NUnit, MBUnit, MS Test, etc).
It is highly extensible and pluggable. Everything in the MVC
framework is designed so that it can
be easily replaced/customized (for
example: you can optionally plug-in
your own view engine, routing policy,
parameter serialization, etc). It
also supports using existing
dependency injection and IOC container
models (Windsor, Spring.Net,
NHibernate, etc).
It includes a very powerful URL mapping component that enables you to
build applications with clean URLs.
URLs do not need to have extensions
within them, and are designed to
easily support SEO and REST-friendly
naming patterns. For example, I could
easily map the /products/edit/4 URL to
the "Edit" action of the
ProductsController class in my project
above, or map the
/Blogs/scottgu/10-10-2007/SomeTopic/
URL to a "DisplayPost" action of a
BlogEngineController class.
The MVC framework supports using the existing ASP.NET .ASPX, .ASCX, and
.Master markup files as "view
templates" (meaning you can easily use
existing ASP.NET features like nested
master pages, <%= %> snippets,
declarative server controls,
templates, data-binding, localization,
etc). It does not, however, use the
existing post-back model for
interactions back to the server.
Instead, you'll route all end-user
interactions to a Controller class
instead - which helps ensure clean
separation of concerns and testability
(it also means no viewstate or page
lifecycle with MVC based views).
The ASP.NET MVC framework fully supports existing ASP.NET features
like forms/windows authentication, URL
authorization, membership/roles,
output and data caching,
session/profile state management,
health monitoring, configuration
system, the provider architecture,
etc.
Primarily, it makes it very easy to create testable websites with well defined separations of responsibility. Its also much easier to create valid XHTML UIs using the new MVC framework.
I've used the 2nd CTP (I think they're on five now) to start work on a website and, having created a few web applications before, I have to say its hundreds of times better than using the server control model.
Server controls are fine when you don't know what you're doing. As you start to learn about how web applications should function, you start fighting them. Eventually, you have to write your own to get past the shortcomings of current controls. Its at this point where the MVC starts to shine. And that's not even considering the testability of your website...
No more auto-generated html IDs!!! Anyone doing any sort of javascript appreciates this fact.
ASP.Net with it's code behind is almost MVC - but not - the one big thing that makes it not is that the codebehinds are tied directly to the aspx's - which is a big component of MVC. If you are thinking of the codebehinds as the controller - the should be completely decoupled from the view. The new .NET MVC rounds this out - and brings a complete MVC framework. Though there are existing ones for .NET already (see Spring.NET).
I looked through a couple simple examples such as this one. I can kind of see the difference. However, I don't really see how MVC uncouples the view from the controller. The view still references stuff that's in the controller. I do see how it makes it much easier to test, and that at least in MVC the controller doesn't have any knowledge of the view. And you wouldn't have to process the view to call methods in the controller. I can see that's quite a leap, even though at first glance it may not seem like much.
I do agree with #Will about fighting server controls. I've never worked in a situation where they were actually used, but many people I know who have, have run into quite a few limitations with them.
Article about ASP.net MVC Vs ASP.net Web form
http://weblogs.asp.net/shijuvarghese/archive/2008/07/09/asp-net-mvc-vs-asp-net-web-form.aspx

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