Data Context w/ Custom Configuration Classes

data-context-with-configurations

using System.Data.Entity;
using System.Data.Entity.ModelConfiguration;
using System.Data.Entity.ModelConfiguration.Conventions;
using EntityFrameworkExtraMile.Web.Domain.Model;

namespace EntityFrameworkExtraMile.Web.DataAccess
{
    public class BlogContext : DbContext
    {
        public BlogContext()
            : base("Blog")
        {
        }

        public DbSet<Author> Authors { get; set; }
        public DbSet<Post> Posts { get; set; }

        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
            base.OnModelCreating(modelBuilder);
            modelBuilder.Conventions.Remove<PluralizingTableNameConvention>(); //Remove the plurals!
            modelBuilder.Configurations.Add(new PostConfiguration());
            modelBuilder.Configurations.Add(new CategoryConfiguration());
            modelBuilder.Configurations.Add(new AuthorConfiguration());
            modelBuilder.Configurations.Add(new JobTitleConfiguration());
        }
    }

    public class PostConfiguration : EntityTypeConfiguration<Post>
    {
        public PostConfiguration()
        {
            HasKey(post => post.ID);
            Property(post => post.Title).HasMaxLength(150).IsRequired();
            Property(post => post.Title).IsRequired();

            HasRequired(post => post.Author)
                .WithMany(author => author.Posts)
                .Map(configuration => configuration.MapKey("AuthorID"));

            HasRequired(post => post.Category)
                .WithMany(category => category.Posts)
                .Map(post => post.MapKey("PostCategoryID"));
        }
    }

    public class CategoryConfiguration : EntityTypeConfiguration<Category>
    {
        public CategoryConfiguration()
        {
            HasKey(cat => cat.ID);
            Property(cat => cat.Name).HasMaxLength(50).IsRequired();
        }
    }

    public class AuthorConfiguration : EntityTypeConfiguration<Author>
    {
        public AuthorConfiguration()
        {
            HasKey(author => author.ID);
            Property(author => author.Name).HasMaxLength(50).IsRequired();
            Property(author => author.TwitterHandle).HasMaxLength(50);

            HasOptional(author => author.JobTitle)
                .WithMany(title => title.Authors)
                .Map(author => author.MapKey("JobTitleID"));
        }
    }

    public class JobTitleConfiguration : EntityTypeConfiguration<JobTitle>
    {
        public JobTitleConfiguration()
        {
            HasKey(title => title.ID);
            Property(title => title.Title).HasMaxLength(50).IsRequired();
        }
    }
}