using System.ComponentModel.DataAnnotations;

namespace BookStore.Models
{
    public class Book
    {
        public int Id { get; set; }

        [MaxLength(17)]
        public string ISBN { get; set; }

        [MaxLength(1024)]
        public string Title { get; set; }

        [MaxLength(1024)]
        public string Author { get; set; }

        public decimal Price { get; set; }

        public Address Location { get; set; }

        public Press Press { get; set; }
    }

    public class Press
    {
        public int Id { get; set; }

        [MaxLength(1024)]
        public string Name { get; set; }

        [MaxLength(1024)]
        public string Email { get; set; }

        public Category Category { get; set; }
    }

    public enum Category
    {
        Book,
        Magazine,
        EBook
    }

    public class Address
    {
        [MaxLength(1024)]
        public string City { get; set; }

        [MaxLength(1024)]
        public string Street { get; set; }
    }
}

using BookStore.Models;
using Microsoft.OData.Edm;
using Microsoft.OData.ModelBuilder;

private static IEdmModel GetEdmModel()
{
    ODataConventionModelBuilder builder = new ODataConventionModelBuilder();
    builder.EntitySet<Book>("Books");
    builder.EntitySet<Press>("Presses");
    return builder.GetEdmModel();
}

using Microsoft.EntityFrameworkCore;

namespace BookStore.Models
{
    public class BookStoreContext : DbContext
    {
        public BookStoreContext(DbContextOptions<BookStoreContext> options)
          : base(options)
        {
        }
     
        public DbSet<Book> Books { get; set; }
        public DbSet<Press> Presses { get; set; }
     
        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            // TODO: Replace the PERM value with your own.
            //       If the Default Database does not exist, EFCore will create it
            //       using this and other supported Model annotations. See the
            //       Teradata EFCore Provider documentation for more information.
            modelBuilder.ForTeradataUseStorageOptions("PERM = 1E7*(HASHAMP()+1)");
            
            modelBuilder.Entity<Book>().OwnsOne(c => c.Location);
        }
    }
}

using Microsoft.AspNetCore.OData;
using Microsoft.EntityFrameworkCore;

public Startup(IConfiguration configuration)
{
    Configuration = configuration;
}

public IConfiguration Configuration { get; }

public void ConfigureServices(IServiceCollection services)
{
    services
        .AddDbContext<BookStoreContext>(opt => opt.UseTeradata(Configuration.GetConnectionString("TeradataConnectionString")))
        .AddControllers().AddOData(opt => opt.AddRouteComponents(GetEdmModel()).EnableQueryFeatures());
}

public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
    if (env.IsDevelopment())
    {
        app.UseDeveloperExceptionPage();
    }
    else
    {
        app.UseExceptionHandler("/Error");
    }

    app.UseStaticFiles();
    app.UseRouting();
    app.UseAuthorization();
    app.UseEndpoints(endpoints => { endpoints.MapControllers(); });
}

using System.Collections.Generic;
using BookStore.Models;

namespace BookStore
{
    public static class DataSource
    {
        private static IList<Book> _books { get; set; }

        public static IList<Book> GetBooks()
        {
            if (_books != null)
            {
                return _books;
            }

            _books = new List<Book>();

            // book #1
            Book book = new Book
            {
                Id = 1,
                ISBN = "978-0-321-87758-1",
                Title = "Essential C#5.0",
                Author = "Mark Michaelis",
                Price = 59.99m,
                Location = new Address { City = "Redmond", Street = "156TH AVE NE" },
                Press = new Press
                {
                    Id = 1,
                    Name = "Addison-Wesley",
                    Category = Category.Book
                }
            };
            _books.Add(book);

            // book #2
            book = new Book
            {
                Id = 2,
                ISBN = "063-6-920-02371-5",
                Title = "Enterprise Games",
                Author = "Michael Hugos",
                Price = 49.99m,
                Location = new Address { City = "Bellevue", Street = "Main ST" },
                Press = new Press
                {
                    Id = 2,
                    Name = "O'Reilly",
                    Category = Category.EBook,
                }
            };
            _books.Add(book);

            return _books;
        }
    }
}

using System.Linq;
using BookStore.Models;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.OData.Query;
using Microsoft.AspNetCore.OData.Routing.Controllers;

namespace BookStore.Controllers
{
    public class BooksController : ODataController
    {
        private BookStoreContext _db;

        public BooksController(BookStoreContext context)
        {
            _db = context;

            // TODO: use EFCore Migrations or _db.Database.EnsureCreated() to create the database and tables
            _db.Database.EnsureCreated();

            // populate the database if it's empty
            if (context.Books.Count() == 0)
            {
                foreach (var b in DataSource.GetBooks())
                {
                    context.Books.Add(b);
                    context.Presses.Add(b.Press);
                }
                context.SaveChanges();
            }
        }

        [EnableQuery]
        public IActionResult Get()
        {
            return Ok(_db.Books);
        }

        [EnableQuery]
        public IActionResult Get(int key)
        {
            return Ok(_db.Books.FirstOrDefault(c => c.Id == key));
        }

        [EnableQuery]
        public IActionResult Post(/*[FromBody]*/ Book book)
        {
            _db.Books.Add(book);
            _db.SaveChanges();
            return Created(book);
        }
    }
}