I Use EF Code First, and lazy loading.
My problem relates to how to efficiently update an entity in within a grandchild collection. First of all, i fear this makes a lot of calls in the db that is not really needed. But if my domain class is not to care about persitance, I cant see another way to do this.
Here is the classes:
public class Supplier
{
public int Id {get;set;}
//...Supplier properties
public virtual ICollection<Contract> Contracts {get;set;}
//supplier methods
}
public class Contract
{
public int id {get;set;}
public int SupplierId{get;set;}
//---Contract properties
[ForeignKey("SupplierId")]
public virtual Supplier Supplier {get;set;}
public virtual ICollection<DeliveryContract> DeliveryContracts {get;set;}
}
public class DeliveryContract
{
public int Id {get;set;}
public bool DeliveryOnMonday{get;set;}
public bool DeliveryOnTuesday{get;set}
//...30 different Delivery terms properties
public Department Department {get;set;}
public int ContractId {get;set;}
[ForeignKey("ContractId")
public virtual Contract Contract {get;set;}
}
The Supplier is the aggregate Root. So i have a method on the supplier which is ChangeDeliveryContract, and that corresponds to what would happen in the real world.
public class Supplier
{
//properties
public void ChangeDeliveryContract (DeliveryContract cahangedDc)
{
//So from the supplier i have to find the contract to change
var dcToUpdate = Contracts
.SingleOrDefault(c=>c.Id == changedDc.ContractId)
.SingleOrDefalut(dc=>dc.Id == changedDc.Id);
//So... what do i do now? Map all 30 properties from changedDc to DcToUpdate
//Some business rules is also applied here i.e. there can only be one
// DeliveryContract between Supplier and Department
}
}
I use MVC so the program would look something like: public ActionResult Update (DeliveryContract changedDc, int supplierId)
{
var Supplier = supplierRepository.GetById(supplierid);
supplier ChangeDeliveryContract (changedDc);
supplierRepository.Save();
//More code...
}
First of all, the problem lays in the ChangeDeliveryContract. I've not been able to get this to work. Also, i feel querying through collections like I do might be inefficient. Third, mapping 30 + properties also feels a bit wrong.
How do you guys do it, and is there a best practices here.
