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c#.net-coreautofac

Injecting AppDbContext with constructor with params exception


I am trying to use AppDbContext (belongs to entity framework core), in one of my classes and instantiate it with autofac, here's how it looks like:

public class AppDbContext : IdentityDbContext<ApplicationUser>
{
    public AppDbContext(DbContextOptions<AppDbContext> options) : base(options)
    {

    }

    protected override void OnModelCreating(ModelBuilder builder)
    {
        builder.Entity<Message>().Property(m => m.Service).HasConversion<int>();
        builder.Entity<ApplicationUser>().HasMany<Message>(m => m.Messages).WithOne(u => u.User).IsRequired();
        base.OnModelCreating(builder);
    }


    public DbSet<Message> Messages { get; set; }
    public DbSet<UsersCredentialsModel> UsersCredentialsModels { get; set; }
    public DbSet<CookieModel> CookieModel { get; set; }


}

I am having a hard time fully understanding on how to implement this correctly.could anyone throw a bone?

public static IContainer Startup()
{
    var builder = new ContainerBuilder();
   // builder.RegisterType<AppDbContext>().As<IdentityDbContext<ApplicationUser>>().InstancePerRequest();

    builder.RegisterType<Application>().As<IApplication>();
    builder.RegisterType<RabbitMQImpl>().As<IListenerQueue>().SingleInstance();
    builder.RegisterType<BotFactory>().As<IBotFactory>();
    var instance = QuartzInstance.Instance;
    builder.RegisterType<QueueImpl>().AsImplementedInterfaces();
    builder.RegisterType<ConsumerSchechuler>().AsImplementedInterfaces();
    builder.RegisterType<SchedulerImpl>().AsImplementedInterfaces();
    builder.RegisterModule(new QuartzAutofacJobsModule(typeof(ConsumerSchedulerJob).Assembly)).RegisterAssemblyModules();
    builder.RegisterModule(new QuartzAutofacJobsModule(typeof(DailyCleanUpJob).Assembly)).RegisterAssemblyModules();
    builder.RegisterInstance(QuartzInstance.Instance).AsImplementedInterfaces();
    return builder.Build();

this is the error that I am getting.

DependencyResolutionException: None of the constructors found with 'Autofac.Core.Activators.Reflection.DefaultConstructorFinder' on type 'JobsImpl.DailyCleanUpJob' can be invoked with the available services and parameters: Cannot resolve parameter 'Utils.AppDbContext context' of constructor 'Void .ctor(Utils.AppDbContext)'.


Solution

  • A friend helped me out with this one:

    If you're facing the same issue here is the code:

    var contextOptions = new DbContextOptionsBuilder<AppDbContext>().Options;
    
    //... configure options as necessary
    
    builder.RegisterInstance(contextOptions).As<DbContextOptions<AppDbContext>>();
    builder.RegisterType<IdentityDbContext>();
    builder.RegisterType<AppDbContext>();
    

    Because the constructor of AppDbContext is receiving an instance of DbContextOptions<AppDbContext> you need to instantiate it fist, then register the instance as DbContextOptions<AppDbContext>.