Re: Beginners DDD question, getting data in domain class

The answer simply is EF is not a DDD construction set. That is, EF is a
tool that lets you express an implementation but it is not a DDD solution.
DDD is more about the communication of ideas and concerns in the domain. I
would say you should get the data in an organized manner. You should use a
bounded context, you should consider whether your update locking strategy
is in line with the notion of aggregate roots. Lazy loading is probably a
good strategy to keep the controller happy.

Pluralsight has a course on Entity Framework in the Enterprise that talks
about a particular DDD implementation strategy. I am reviewing the material
because I have a new project that wants to use EF to do DDD. I am not done
with it yet, but I like what I am seeing so far.

Michael


On Tue, Dec 3, 2013 at 1:02 PM, <[email protected]> wrote:

>
>
> I posted this on StackOverflow too, but I thought I might get better
> answers here. I think I've read 16,154 questions, blog posts, tweets, etc
> about DDD and best practices. Apologies for yet another question of that
> type. Let's say I have three tables in my database, User, Department, and
> UserDepartment. All very simple. I need to build a hierarchy showing what
> departments a user has access to. The issue is that I also need to show the
> parent departments of those that they have access to.
>
>
> Is it best to have a GetDepartments() method on my user class? Right now I
> have a user service with GetDepartments(string userName), but I don't feel
> like that is the optimal solution. If user.GetDepartments() is preferred
> then how do I get access the repository to get the parent departments for
> those that the user has access to?
>
>
> For example, let's say a user has permissions to Department2. The parent
> of Department2 is Department1, so the list of departments returned should
> include them both.
>
>
> Don't know that it matters, but I'm using the Entity Framework.
>
>
> public class User
>
> {
>
>     [Key]
>
>     public int UserId { get; private set; }
>
>
>     [Display(Name = "User Name")]
>
>     public string UserName { get; private set; }
>
>
>     [Display(Name = "Email")]
>
>     public string Email { get; private set; }
>
>
>     [Display(Name = "UserDepartments")]
>
>     public virtual ICollection<UserDepartment> UserDepartments { get;
> private set; }
>
>
>     public List<Department> GetDepartments()
>
>     {
>
>         // Should this be here? and if so, what's the preferred method for
> accessing the repository?
>
>     }
>
> }
>
>
> It seems like a function of the domain to me, but maybe I should just
> leave it in the service.
>
>
> Thanks for any help. I really appreciate it.
>
>
> Nick
>
>  
>