dbml generator

dbml.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Metadata;

namespace BiFrost.Web.DataManagement
{
    public class EFDBMLService<TDbContext>
        where TDbContext : DbContext
    {
        private readonly TDbContext context;

        public EFDBMLService(TDbContext context)
        {
            this.context = context;
        }

        public string GenerateDBMLDocument()
        {
            var stringBuilder = new StringBuilder();

            GenerateProject(stringBuilder);

            GenerateTables(stringBuilder);

            return stringBuilder.ToString();
        }

        private void GenerateProject(StringBuilder stringBuilder)
        {
            var rel = context.Model.Relational();

            stringBuilder.AppendLine("Project " + rel.DefaultSchema + " {");
            stringBuilder.AppendLine('\t' + "database_type: " + "'SQLServer'");
            stringBuilder.AppendLine("}");
            stringBuilder.AppendLine();
        }

        private void GenerateTables(StringBuilder stringBuilder)
        {
            var types = context.Model.GetEntityTypes().ToList();

            foreach (var type in types)
            {
                if (type.IsOwned())
                {
                    continue;
                }

                var rel = type.Relational();

                stringBuilder.AppendLine("Table " + rel.TableName + " {");

                var props = type.GetProperties().Where(x => !x.IsShadowProperty).ToList();
                foreach (var prop in props)
                {
                    GenerateProps(stringBuilder, prop);
                }

                var navs = type.GetNavigations().Where(x => !x.IsShadowProperty).ToList();
                foreach (var nav in navs)
                {
                    GenerateNavs(stringBuilder, nav);
                }

                stringBuilder.AppendLine("}");
                stringBuilder.AppendLine();
            }
        }

        private void GenerateNavs(StringBuilder stringBuilder, INavigation nav)
        {
            if (nav.IsCollection() || nav.IsDependentToPrincipal()) { return; }

            var type = nav.DeclaringType.Model.FindEntityType(nav.ClrType);

            if (type == null) { return; }

            var props = type.GetProperties().Where(x => !x.IsShadowProperty).ToList();
            foreach (var prop in props)
            {
                GenerateProps(stringBuilder, prop);
            }
        }

        private void GenerateProps(StringBuilder stringBuilder, IProperty prop)
        {
            var rel = prop.Relational();

            if (prop.ClrType.IsEnum)
            {
                stringBuilder.AppendLine('\t' + rel.ColumnName + " " + prop.ClrType.Name);
            }
            else
            {
                var foreings = prop.GetContainingForeignKeys();

                var stringBuilder2 = new StringBuilder();

                foreach (var foreing in foreings)
                {
                    var rel2 = foreing.Relational();

                    var propsFk = foreing.PrincipalKey.Properties;

                    foreach (var propFk in propsFk)
                    {
                        var t = propsFk.FirstOrDefault().DeclaringEntityType.Relational().TableName;
                        var p = propsFk.FirstOrDefault().Relational().ColumnName;

                        stringBuilder2.Append(" [ref: > " + t + "." + p + "]");
                    }

                }

                stringBuilder.AppendLine('\t' + rel.ColumnName + " " + rel.ColumnType + stringBuilder2.ToString());
            }

        }
    }
}