EF Code First Fluent Configuration of Abstract Entities

Introduction

When I was building my set of POCOs, I saw commonality in some fields and created abstract classes to represent these fields. The main entities then inherited from these, however when I came to configure the EF more exactly, I found it wasn't obvious how to do it.

Using the Code

So if you have an entity defined like:

public class UnitType : ListValidRange
{
    public int Id { get; set; }
    public string Name { get; set; }
    [Display(Name = "Possible Review Types")]
    public virtual ICollection<ReviewType> ReviewTypes { get; set; }
}

Where ListValidRange is:

public abstract class ListValidRange : AuditInfo, IValidatableObject
{
    [DataType(DataType.Date)]
    public DateTime ValidFrom { get; set; }
    [DataType(DataType.Date)]
    public DateTime ValidTo { get; set; }

    #region IValidatableObject Members
    public System.Collections.Generic.IEnumerable<ValidationResult> Validate
        (ValidationContext validationContext)
    {
        if (ValidFrom > ValidTo || ValidTo == ValidFrom)
             yield return new ValidationResult(
                 "ValidFrom must be different from, and occur earlier than, ValidTo."
        //if both fields are mentioned, then you get duplicate messages
        //well no you get the same message for both fields
        //but once you receive it from the DataServices they've doubled!
                 , new[] { "ValidFrom" });
    }
    #endregion
}

Now to the fluent configuration, the simple (and well documented way) is to configure ValidFrom/ValidTo on UnitType, but that's time consuming if a lot of entities have those fields.

So to configure ListValidRange, you need to use the Types() collection of the modelBuilder in your OnModelCreating method, like so:

modelBuilder
    .Types<ListValidRange>()
    .Configure(p => p.Property(e => e.ValidFrom)
                     .HasColumnType("date"));

So it's slightly different from the examples you've probably already been looking at, but I hope it's easy to see how it works and can be expanded to suit your needs.