AutoFac / .NET Core - Register DBcontext

Question

I have a new .NET Core Web API project that has the following projects structure:

API -> Business / Domain -> Infrastructure

The API is very thin with only the API methods. The Business / Domain layer has all my business logic. And finally, my Infrastructure layer has my DB classes using EF Core 2.0.

I know using .NET Core built-in Dependency Injection I can add a reference from the API project to the Infrastructure project, then add the following code in the StartUp.cs file:

services.AddDbContext<MyContext>(options => options.UseSqlServer(connectionString)); 

However, I would like to maintain a more traditional separation of concerns. So far I have added a module in my Infrastructure layer that attempts to make the registration like so:

builder.Register(c =>         {             var config = c.Resolve<IConfiguration>();              var opt = new DbContextOptionsBuilder<MyContext>();             opt.UseSqlServer(config.GetSection("ConnectionStrings:MyConnection:ConnectionString").Value);              return new MyContext(opt.Options);         }).AsImplementedInterfaces().InstancePerLifetimeScope(); 

The DBContext, however, is not getting registered. Any class that attempts to access the injected DBContext cannot resolve the parameter.

Is there a way to register the DBContext in a separate project using AuftoFac in a .NET Core Web API Project?

Answer 1

I use Autofac to register both HttpContextAccessor and DbContext.

builder     .RegisterType<HttpContextAccessor>()     .As<IHttpContextAccessor>()     .SingleInstance();  builder     .RegisterType<AppDbContext>()     .WithParameter("options", DbContextOptionsFactory.Get())     .InstancePerLifetimeScope(); 

DbContextOptionsFactory

public class DbContextOptionsFactory {     public static DbContextOptions<AppDbContext> Get()     {         var configuration = AppConfigurations.Get(             WebContentDirectoryFinder.CalculateContentRootFolder());          var builder = new DbContextOptionsBuilder<AppDbContext>();         DbContextConfigurer.Configure(             builder,              configuration.GetConnectionString(                 AppConsts.ConnectionStringName));          return builder.Options;     } } 

DbContextConfigurer

public class DbContextConfigurer {     public static void Configure(         DbContextOptionsBuilder<AppDbContext> builder,          string connectionString)     {         builder.UseNpgsql(connectionString).UseLazyLoadingProxies();     } }