i'm in a project with a service layer (WCF), a proxy layer that are between this service layer and the "controllers". Every controller should call this proxy layer to get data, and instead return a model to be rendered, returns a bigger entity that i've to convert using Linq to a more little model. Then pass it to the view.
Do you think is a good idea that this conversion be done by the controller? In my opinion the controller is not the responsable to shape the incoming object from the proxy layer. This object should be returned by the proxy layer and the controller should pass it to the view directly.
Are this way of thinking good or im wrong?
Perhaps you should consider adding a ViewModel, so you end up with a MVVMC pattern. This will ensure that your controller doesn't need to handle any of the dataconversion.
Related
Here's my problem.
I'm using SOAP to retrieve information from a third-party web service.
Response time is too high, so I was planning on using JSON instead, at least in a couple of methods.
For this I'm using DataContractJsonSerializer, but I seem to be having some trouble.
For example, in SOAP there's a method called getAvailablePublic with returns an object of type getAvailablePublicResponse.
There's an equivalent for this method in JSON, which also returns a an object of type getAvailablePublicResponse.
In order to deserialize the information I needed to create a couple of data contracts, and here are my concerns:
Do I really need to create a DataContract? Why can't I use getAvailablePublicResponse object from asmx?
The problem is that if I create a DataContract, I need to use a different name other than getAvailablePublicResponse, as I would have two objects with the same name (the one created by me, and the one from SOAP), and this would require making several changes in my solution.
Hope this makes sense.
Thanks.
Can you post your client code that is making the call to the web service? I don't know what you are using now, but I'm a fan of RestSharp for making remote calls and serializing JSON to C# classes. Something like this:
RestClient client = new RestClient("http://some.domain.com/someservice?someparam=yes");
var results = client.Execute<MyGreatDTOClass>(new RestRequest(Method.GET));
I have a quick question on scope of ModelAttributes.
Dev. Env: Spring MVC 3.1/Java 6/JSP w/JSTL for Views
In my controller, I add an attribute to the model via
model.addAttribute(“appForResubmission”, appForResubmission);
In the JSP(served out in response to a GET request) I read it’s contents as:
${appForResubmission.appId}
— works fine and the data is shown on JSP as expected.
Upon submission of the JSP, in the same controller in a different method(in response to a PUT request), I try to read the attributes from the Model for any changes and I am doing this as
#ModelAttribute(“appForResubmission”) Application app
in the method signature.
However, all I get is a new Application object when I try to interrogate the object for data. Spring’s documentation says this kind of instantiation of a new object happens when the requested attribute does not exist in the Model.
What would cause the attribute to be lost? Any ideas? I am suspecting it is a scope issue someplace but I am not sure where the problem could be.
Any pointers you could provide is greatly appreciated?
Thank you,
M. Reddy
The scope of a modelattribute is the request, internally it is just equivalent to HttpSerletRequest.setAttribute("model", model).
If you want the model to be available in a different controller you probably have two options, one is to reconstruct it, based on what you submit to the controller or using your persistent source. The second option is for specific model attributes to be added to the session using #SessionAttribute({'modelname'}), but just be careful that you have to call SessionStatus.complete to remove the model added to the session later.
I have a 3-tier web application wit ha bunch of simple forms. One to list records, one to edit a single record, etc. The works.
I have a DataLayer where my EDMX is.
I have an App Layer where my POCOs are.
I haev a BusinessLayer with all my controller classes, etc. (not MVC!)
I have a UI layer where my web UI is.
The EDMX has many, many tables wit ha lot of navigation properties.
Of course, when I fetch the data in one of my controllers, e.g. GetCustomerById(int id), I create the Object context and close it when I'm done.
However, the ObjectContext is out of scope when I try to access the navigation properties in the UI layer.
Should I do (using MyContext = new MyContext()) {... } in the web layer?? that does not seem right.
Should I create another set of POCOs that I populate from the entities' data from the BizLayer?
What happens when I want to save data entered in a web form? Would I call a BizLayer controller e.g. SaveCustomer()?
My question is, how do you design the web UI layer if I want to be able to properly access the navigation properties of an entity?
Note:
EDMX is set to LazyLoading.
You want to use lazy loading in UI but it means that UI defines lifetime of your ObjectContext. There are many ways to achieve this without exposing the context to UI. You can for example use this simple approach:
You mentioned some controller which uses context and disposes it. So make your controller disposable and instead of disposing context in every method use single context for whole lifetime of the controller. Dispose the context in controller's Dispose method.
Instantiate your controller per request. So for example you can create instance of controller in Page.Load and dispose it in Page.Unload.
Use your controller and entities as you want. Whole processing of the request (between Load and Unload) will be in scope of single living context.
Anyway you should not need lazy loading in Web application too much. In your form you usually know exactly what entities you need so you should request them directly with eager loading.
I have developed webservices using CXF framework. We are exposing all our Database operation(Service Layer) methods as a web service methods. We are using Hibernate for persistence.
For example consider I have one Java POJO class(for hibernate mapping)
named CountryEntity.java with the following
properties(ID,Name,ModifiedDate).
Inside my service layer i have two methods called
#WebMethod
public CountryEntity createCountryEntity(CountryEntity countryEntity);
#WebMethod
public CountryEntity getCountryEntityById(long id);
Based on JAX-WS documentation i understand that it is using JAXB to do
the databinding. When user calling my webservice for creating the new
Country record i dont want the user to send the Id value and Modified
Date value . So what i done is i annotated the propeties(id,modified
date) inside the CountryEntity.java with #XmlTransistent annotation.
So that operation is working fine.
But when i call getCountryEntityById web service method its returning
CountryEntity object but that object dont have the values for ID and
Modified Date property. I understand because of XMLTransistent
annotation the values not getting Marshalling.
Can i change my method createCountryEntity taking parameters like
(String countryName) , so that i no need to include XMLTransistent
annotation in my entity classes.? or Anyother solution for this?
Please help me . Thanks in advance
Since no answer i go with parameters instead of sending an object as parameter. Thank you.
I am new to the MVC way of programming so please bear with my basic question !
I have a Status class with a default constructor (in an ASP.NET MVC application).
public Status()
{
this.DatePosted = DateTime.Now;
}
I noticed Fluent NHibernate calls this constructor each time it fetched a list of existing Status objects from the database. Hence, the constructor does not seem like the right place to initialize the date.
Where should I move this initialization ? Moving it to the Controller (Add action of Status controller) also seems to violate the principle that the Controller should not make any business decisions. Should I move it to the Status DAO then ? (In traditional ASP.NET Web Form applications I worked with, a DAO simply accepted a business object and saved it to the database and did not contain any logic)
I would like to know the right way to accomplish this. Is there another layer I am missing here where this initialization should take place?
I noticed Fluent NHibernate calls this
constructor each time it fetched a
list of existing Status objects from
the database. This does not seem right
This is exactly what is supposed to be happening. Why wouldn't an ORM call the default constructor for an object? I think every hand rolled DAL and ORM in the world would trigger DatePosted to be reset because thats just how constructors work.
Your DatePosted property should probably set via ModelBinding or manually in the controller and not be part of a constructor.