Actually read AppSettings in ConfigureServices phase in ASP.NET Core

Question

I need to setup a few dependencies (services) in the ConfigureServices method in an ASP.NET Core 1.0 web application.

The issue is that based on the new JSON configuration I need to setup a service or another.

I can't seem to actually read the settings in the ConfigureServices phase of the app lifetime:

public void ConfigureServices(IServiceCollection services) {     var section = Configuration.GetSection("MySettings"); // this does not actually hold the settings     services.Configure<MySettingsClass>(section); // this is a setup instruction, I can't actually get a MySettingsClass instance with the settings     // ...     // set up services     services.AddSingleton(typeof(ISomething), typeof(ConcreteSomething)); } 

I would need to actually read that section and decide what to register for ISomething (maybe a different type than ConcreteSomething).

Answer 1

That is the way you can get the typed settings from appSettings.json right in ConfigureServices method:

public class Startup {     public Startup(IConfiguration configuration)     {         Configuration = configuration;     }      public IConfiguration Configuration { get; }      public void ConfigureServices(IServiceCollection services)     {         services.Configure<MySettings>(Configuration.GetSection(nameof(MySettings)));         services.AddSingleton(Configuration);          // ...          var settings = Configuration.GetSection(nameof(MySettings)).Get<MySettings>();         int maxNumberOfSomething = settings.MaxNumberOfSomething;          // ...     }      // ... }