728 questions
84
votes
6
answers
36k
views
EF codefirst : Should I initialize navigation properties?
I had seen some books(e.g programming entity framework code first Julia Lerman) define their domain classes (POCO) with no initialization of the navigation properties like:
public class User
{
...
- 7,023
7
votes
4
answers
1k
views
Making Entity Class Closed for Changes
I have a database relationship as shown below. The domain objects are created based on LINQ to SQL ORM.
A payment comprises of Cash Payment and Gift Coupon Payments. Suppose the total amount of ...
19
votes
2
answers
4k
views
Who should handle the conditions in complex queries, the data mapper or the service layer?
this question did a very good job of clearing my confusion a bit on the matter, but I'm having a hard time finding reliable sources on what the exact limitations of the service layer should be.
For ...
- 2,111
310
votes
9
answers
118k
views
Should services always return DTOs, or can they also return domain models? [closed]
I'm (re)designing large-scale application, we use multi-layer architecture based on DDD.
We have MVC with data layer (implementation of repositories), domain layer (definition of domain model and ...
- 6,061
2
votes
2
answers
800
views
Persist Data by Programming Against Interface
I have a IBankAccount interface that I will be passing to the ApplicationService. The changes made on the account objects (in the ApplicationService project) need to be persisted in the database. The ...
- 22.8k
140
votes
9
answers
60k
views
Value vs Entity objects (Domain Driven Design)
I have just started reading DDD. I am unable to completely grasp the concept of Entity vs Value objects.. Can someone please explain the problems (maintainability, performance.. etc) a system could ...
StackUnderflow
11
votes
2
answers
6k
views
How to remove unit of work functionality from repositories using IOC
I have an application using ASP.NET MVC, Unity, and Linq to SQL.
The unity container registers the type AcmeDataContext which inherits from System.Data.Linq.DataContext, with a LifetimeManager using ...
- 7,408
79
votes
2
answers
22k
views
How are Value Objects stored in the database?
I haven't really seen any examples, but I assume that they are saved inside the containing entity table within the database.
Ie. If I have a Person entity/aggregate root and a corresponding Person ...
- 11.7k
36
votes
5
answers
22k
views
MVVM: Binding to Model while keeping Model in sync with a server version
I've spent quite some time to try and find an elegant solution for the following challenge. I've been unable to find a solution that's more than a hack around the problem.
I've got a simple setup of ...
- 1,213
12
votes
2
answers
6k
views
ASP.MVC: Repository that reflects IQueryable but not Linq to SQL, DDD How To question
I want to create a DDD repository that returns IQueryable Entities that match the Linq to SQL underlying classes, minus any relations. I can easily return Entities minus the relations with a Linq ...
- 21.3k
41
votes
6
answers
26k
views
Communicating between two Bounded Contexts in DDD
I have few different Bounded Contexts in the domain. The validation of a CRUD operation is built in each Bounded Context.
For example, I can create an entity called GAME only if the person creating ...
- 11.7k
4
votes
1
answer
1k
views
IQueryable & Repositories - take 2?
I have to admit I have been carrying the "Repository should not return IQueryable" banner because it is harder to test. I have been influenced by the answers to other questions like this and this.
...
- 19.9k
1
vote
1
answer
792
views
Polymorphism: Is ORM entity a Domain Entity or Data Entity?
I have a BankAccount table. LINQ to SQL generates a class named “BankAccount” as shown below.
[global::System.Data.Linq.Mapping.TableAttribute(Name="dbo.BankAccount")]
public partial class ...
- 22.8k
37
votes
4
answers
5k
views
How to handle set based consistency validation in CQRS?
I have a fairly simple domain model involving a list of Facility aggregate roots. Given that I'm using CQRS and an event-bus to handle events raised from the domain, how could you handle validation ...
- 2,963
28
votes
3
answers
15k
views
Why does the entity framework need an ICollection for lazy loading?
I want to write a rich domain class such as
public class Product
{
public IEnumerable<Photo> Photos {get; private set;}
public void AddPhoto(){...}
public void ...
Akk
94
votes
5
answers
82k
views
DDD - which layer DTO should be implemented
I am learning about DDD so apologies if my question is naive. I think I need to use Local Data Transfer Object in order to display data to the users as a lot of properties are not part of any of ...
- 951
43
votes
2
answers
40k
views
DDD, Anti Corruption layer, how-to?
At the moment, we have to build an application which is based on a legacy one. Code for that old application should be thrown away and rewritten, but as it usually goes - instead of rewriting it, we ...
- 47.6k
136
votes
8
answers
66k
views
DTO = ViewModel?
I'm using NHibernate to persist my domain objects.
To keep things simple I'm using an ASP.NET MVC project as both my presentation layer, and my service layer.
I want to return my domain objects in ...
- 4,413
74
votes
5
answers
47k
views
Rest API and DDD
In my project using DDD methodology.
The project has the aggregate(entity) Deal. This aggregate has many of use cases.
For this aggregate I need to create a rest api.
With standard: create and ...
- 1,263
54
votes
6
answers
52k
views
Repository pattern and mapping between domain models and Entity Framework
My repositories deal with and provide persistence for a rich domain model. I do not want to expose the anemic, Entity Framework data entity to my business layers, so I need some way of mapping ...
- 40.3k
32
votes
3
answers
20k
views
DDD Using Specification pattern for Validation
I am thinking of using Specification pattern for validation purposes. The hard thing is how to tell the user why some Specification was not satisfied. What if the Specification.IsSatisfiedBy() will ...
- 3,635
13
votes
3
answers
11k
views
Program Design - Package by Feature vs. Layer or Both?
I am in the design stage of a web application that allows users to create requests of work and the workers to put time against those requests. The application will also have reporting capabilities for ...
- 491
2
votes
3
answers
5k
views
Unit Testing without Database: Linq to SQL
I have a repository implemented using LINQ to SQL. I need to do Unit Testing though I don't have a database. How can I write the UT for FreezeAllAccountsForUser method? Can you please show an example ...
- 22.8k
91
votes
2
answers
26k
views
Access Control in Domain Driven Design
I read about DDD and Access Control, and I found some contradiction between the following two opinions:
"security concerns should be handled outside the domain"
"access control ...
- 26.3k
50
votes
7
answers
8k
views
What is domain driven design? [closed]
So I got this question from one of the developers in my team: What is domain driven design? I could of course point to the book from Evans but is that actually an answer?
How would you explain DDD ...
- 1,431