Disposing dependencies in ASP.NET application with Hangfire

Question

Typically in my ASP.NET MVC application that uses Unity as dependency framework i use PerRequestLifetimeManager which disposes all the dependencies when HTTP request completes.

Now i configured Hangfire into ASP.NET application. Hangfire schedules a background job that has dependency on DBContext. Something like below

(The IGenericRepository use DBContext but for brevity purpose that code is not shown here)

public interface IMyService:IDisposable
{
    void DoWork();
}

public class MyService : IMyService
{
    private bool _disposed = false;

    protected readonly IGenericRepository _repository = null;        

    public MyService(IGenericRepository repository)
    {
        _repository = repository ?? throw new ArgumentNullException(nameof(repository));            
    }

    public void DoWork()
    {

    }


    public void Dispose()
    {
        Dispose(true);
        GC.SuppressFinalize(this);
    }

    protected virtual void Dispose(bool disposing)
    {
        if (_disposed)
            return;

        if (disposing)
        {
            if (_repository != null)
            {
                _repository.Dispose();
            }
            // Free any other managed objects here.                    
        }

        // Free any unmanaged objects here.
        _disposed = true;
    }
}

}

and then on application startup i register a recurring job like below

RecurringJob.AddOrUpdate<IMyService>(x => x.DoWork(), Cron.Hourly());

I understand that i cannot use PerRequestLifetimeManager because there wont be HttpContext available when Hangfire schedules a background job. But i wanted to know what lifetime manager i should be using here to register IGenericRepository and IMyService so that Dispose method will get invoked implicitly as soon as the job is done.

score 1 · Answer 1 · answered Jul 23 '18 at 22:41

I found the answer Resolving type with PerRequestLifetimeManager without HTTP request

I have to use HierarchicalLifetimeManager

and then Change this...

GlobalConfiguration.Configuration.DependencyResolver = 
    new Unity.WebApi.UnityDependencyResolver(container);

to this...

GlobalConfiguration.Configuration.DependencyResolver = 
    new Unity.WebApi.UnityHierarchicalDependencyResolver(container);

Disposing dependencies in ASP.NET application with Hangfire

1 Answers1