Inheritance with Repository Pattern

Question

I’m studying and trying to implement the Repository Pattern in C# however I am having some difficulties in solving certain problems with inheritance among my classes of Repository, for example the inheritance between Pessoa, PessoaFisica and PessoaJuridica, where I created 3 classes, PessoaRepository, PessoaFisicaRepository, PessoaJuridicaRepository, where PessoaFisicaRepository and PessoaJuridicaRepository are inheriting from PessoaRepository. My problem is that class PessoaRepository is allowing to include a Personal or Personal, but their respective classes Respository would have specific business rules, then class PessoaRepository, could not include its derivatives, remembering that I am also trying to follow some concepts of SOLID.

My classes are: Model

[Table("Pessoa")]
public class PessoaEntity: IEntity
{
    [Key]
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int PessoaId { get; set; }

    [Required]
    [MaxLength(100)]
    public string Nome { get; set; }

    [MaxLength(14)]
    public string CpfCnpj { get; set; }
}

[Table("PessoaFisica")]
public class PessoaFisicaEntity : PessoaEntity, IEntity
{
    public string NumeroRg { get; set; }
    public Sexo Sexo { get; set; }
}

[Table("PessoaJuridica")]
public class PessoaJuridicaEntity : PessoaEntity
{
    [MaxLength(100)]
    public string NomaFantasia { get; set; }
}

public enum Sexo
{
    Masculino = 1,
    Feminino = 2
}

public class PessoaContext : DbContext
{
    public DbSet<PessoaEntity> Pessoa { get; set; }
    public DbSet<PessoaFisicaEntity> PessoaFisica { get; set; }
    public DbSet<PessoaJuridicaEntity> PessoaJuridica { get; set; }
    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();

        base.OnModelCreating(modelBuilder);
    }
}

Meu Repository:

    public class Repository<TEntity, TContext> : IRepository<TEntity>
    where TEntity : class, IEntity
    where TContext : DbContext, new()
{
    protected TContext _context;

    public Repository()
    {
        _context = new TContext();
    }

    public virtual TEntity Find(params object[] keyValues)
    {
        return _context.Set<TEntity>().Find(keyValues);
    }

    public virtual void InsertOrUpdate(TEntity obj)
    {
        var entity = Find(GetKeyValue(obj));
        if (entity == null)
            _context.Set<TEntity>().Add(obj);
        else
        {
            entity = obj;
        }

        _context.SaveChanges();
    }

    public virtual void Delete(params object[] keyValues)
    {
        _context.Set<TEntity>().Remove(Find(keyValues));
        _context.SaveChanges();
    }

    public virtual void Save()
    {
        _context.SaveChanges();
    }


    private object[] GetKeyValue<T>(T entity) where T : class
    {
        var properties = entity.GetType().GetProperties();
        var keysProperties = properties.Where(p => p.GetCustomAttributes(typeof(KeyAttribute), true).Length != 0);

        List<object> retorno = new List<object>();

        foreach (var key in keysProperties)
        {
            retorno.Add(key.GetValue(entity, null));
        }

        return retorno.ToArray();
    }

}

public class PessoaRepository<TPessoa> : Repository<TPessoa, PessoaContext>
    where TPessoa : PessoaEntity, IEntity
{
    public override void InsertOrUpdate(TPessoa obj)
    {
        if (ConsisteInsertOrUpdate(obj))
        {
            base.InsertOrUpdate(obj);
        }
    }

    private bool ConsisteInsertOrUpdate(PessoaEntity obj)
    {
        if (!String.IsNullOrWhiteSpace(obj.CpfCnpj))
        {
            var cpfCnpjDuplicados = _context.Pessoa.Where(a => a.CpfCnpj == obj.CpfCnpj && obj.PessoaId != a.PessoaId).Count();

            return cpfCnpjDuplicados == 0;
        }

        return true;
    }
}

public class PessoaFisicaRespository<TPessoaFisica> : PessoaRepository<TPessoaFisica>
    where TPessoaFisica: PessoaFisicaEntity, IEntity
{
    public override void InsertOrUpdate(TPessoaFisica obj)
    {
        if (ConsisteInsertOrUpdate(obj))
        {
            base.InsertOrUpdate(obj);
        }
    }

    private bool ConsisteInsertOrUpdate(PessoaFisicaEntity obj)
    {
        if (!String.IsNullOrWhiteSpace(obj.NumeroRg))
        {
            var numeroRgDuplicados = _context.PessoaFisica.Where(a => a.NumeroRg == obj.NumeroRg && obj.PessoaId != a.PessoaId).Count();

            return numeroRgDuplicados == 0;
        }

        return true;
    }
}

Answer 1

Pablo, do you intend to save this to a database? I don’t know much about this Pattern, but looking at the way the entities were created, it seems to me to be a bit strange.

The way it’s being done, you’ll have tables like Pessoa, and also tables PessoaFisica and PessoaJuridica with the same fields as Pessoa.

It would not be the case to have the 3 entity and, instead of inheritance, use an object of the type Pessoa within the classes of PessoaFisica and PessoaJuridica? It would look something like:

[Table("Pessoa")]
public class PessoaEntity: IEntity
{
    [Key]
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int PessoaId { get; set; }

    [Required]
    [MaxLength(100)]
    public string Nome { get; set; }

    [MaxLength(14)]
    public string CpfCnpj { get; set; }
}

[Table("PessoaFisica")]
public class PessoaFisicaEntity : IEntity
{
    public string NumeroRg { get; set; }
    public Sexo Sexo { get; set; }

    [ForeignKey("Pessoa"), Required, Key]
    public int PessoaId { get; set; }
    public virtual PessoaEntity Pessoa { get; set; }
}

[Table("PessoaJuridica")]
public class PessoaJuridicaEntity : IEntity
{
    [MaxLength(100)]
    public string NomaFantasia { get; set; }

    [ForeignKey("Pessoa"), Required, Key]
    public int PessoaId { get; set; }
    public virtual PessoaEntity Pessoa { get; set; }
}