Real Web Developers

Nhibernate helpers

Parent and child

Models

namespace RealWebDevelopers.Models;

public class Parent
{
    public virtual required string Reference { get; set; }
    public virtual required string Name { get; set; }
    public virtual required ISet<Child> Children { get; set; } = new HashSet<Child>();
}

public class Child
{
    public virtual required string Reference { get; set; }
    public virtual required string Name { get; set; }
    public virtual required Parent Parent { get; set; }
}
    

Mapping

namespace RealWebDevelopers;
public static partial class Extensions
{
    public static IServiceCollection AddNHibernate(this IServiceCollection services)
    {
        services.AddSingleton(factory =>
        {
            // ...
            return Fluently
                .Configure()
                .Database(MySQLConfiguration.Standard
                    .ConnectionString(options.ConnectionString)
                    .ShowSql())
                .Mappings(mappings => mappings.AutoMappings.Add(AutoMap.AssemblyOf()
                        .Where(where => where.Namespace!.Equals("TradingApplication.Models", StringComparison.OrdinalIgnoreCase))
                        .Override(populateMap =>
                        {
                            populateMap.Id(memberExpression => memberExpression.Reference).Not.Nullable().Length(31).GeneratedBy.Assigned();

                            // the next line sets this as the parent. Note the KeyColumn is the name of the column on the Child entity which holds a reference to this Parent
                            populateMap.HasMany(memberExpression => memberExpression.Children).Cascade.AllDeleteOrphan().Inverse().KeyColumn("ParentReference");
                        })
                        .Override(populateMap =>
                        {
                            populateMap.Id(memberExpression => memberExpression.Reference).Not.Nullable().Length(31).GeneratedBy.Assigned();
                            populateMap.References(memberExpression => memberExpression.Parent).Column("ParentReference");
                        })
            // ...
        });
    }
}
    

See associated posts: Service collection Fluent Nhibernate