'Unable to resolve service for type 'Microsoft.Extensions.Logging.ILogger`1[Application.Startup]' while attempting to activate 'Application.Startup'.'

Question

I have an ASP.NET Core 3.0 application. I am getting error as

I Know that ILogger is not default registered in ASP.NET Core 3.0 Application. Below is my code for Program.cs and Startup.cs for reference

public static IHostBuilder CreateHostBuilder(string[] args) =>
    Host.CreateDefaultBuilder(args)
        .ConfigureLogging(logging =>
          {
            logging.ClearProviders();
            logging.SetMinimumLevel(LogLevel.Trace);
          })
        .ConfigureWebHostDefaults(webBuilder =>
        {
          webBuilder.UseStartup<Startup>();
        });

Startup.cs

public void ConfigureServices(IServiceCollection services)
    {
        var serviceProvider = services.BuildServiceProvider();
        var logger = serviceProvider.GetService<ILogger<AnyClass>>();
        services.AddSingleton(typeof(ILogger), logger);
        ...
     }

Please can anyone help me with this error, What I am doing wrong in my case ?

Does this answer your question? [How do I write logs from within Startup.cs](https://stackoverflow.com/questions/41287648/how-do-i-write-logs-from-within-startup-cs) — devNull, Mar 21 '20 at 21:38
No As said in the link for ASP.NET 3.0 followed but still the same error — PDTech, Mar 21 '20 at 21:56
part of the answer in that question is in regards to ASP.NET Core 3.0 — devNull, Mar 21 '20 at 22:11
Why are you resolving the logger just to register it as a Singleton anyways? — devNull, Mar 21 '20 at 22:12
@Claius If I empty all the code from ConfigureServices still it throws error — PDTech, Mar 22 '20 at 06:56
I could not reproduce your issue by using your code.Could you share more details? — Rena, Mar 23 '20 at 09:31

score 5 · Accepted Answer · answered Mar 21 '20 at 20:58

5

As per https://learn.microsoft.com/en-us/aspnet/core/fundamentals/logging/?view=aspnetcore-3.1#create-logs-in-the-startup-class writing logs before completion of the DI container setup in the Startup.ConfigureServices method is not supported.

You cannot do var logger = serviceProvider.GetService<ILogger<AnyClass>>(); since the DI container is not configured yet, at that stage.

More information on the link provided.

answered Mar 21 '20 at 20:58

Mihaimyh

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1

I tried commenting those lines as well, Still it throws error on Line HostBuilder.Build().Run() when I debug – PDTech Mar 21 '20 at 21:06
1

You cleared all providers by doing this `logging.ClearProviders();` and did not add any back. Try adding `logging.AddConsole();` and see how it goes. You might need this nuget package https://www.nuget.org/packages/Microsoft.Extensions.Logging.Console for this extension method. – Mihaimyh Mar 21 '20 at 21:16
1

ILoggingBuilder does not contain definition of AddConsole() Where logging is ILoggingBuilder – PDTech Mar 21 '20 at 21:30
1

AddConsole() gets available while I added In .ConfigureLogging but still the error exists In this case var logger = serviceProvider.GetService>(); was commented – PDTech Mar 21 '20 at 21:36

'Unable to resolve service for type 'Microsoft.Extensions.Logging.ILogger`1[Application.Startup]' while attempting to activate 'Application.Startup'.'

1 Answers1