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c#asp.net-coreautofacioptions

Get a collection of all IOptions objects with autofac


I'd like to be able to get a collection of all IOptions<T> registered in autofac so that I can save them to a custom JSON file. Something like:

class OptionsManager(IEnumerable IOptions)

I don't know if this is even possible because there is not AFAIK a non-generic IOptions interface, and currently I don't actually register the options per se, I build a service collection that adds them, and that gets populates my container via an extension:

var builder = new ContainerBuilder();
var serviceCollection = new ServiceCollection().AddOptions();
builder.Populate(serviceCollection);

Which doesn't expose any way for me to reigster the these options under a single interface anyways.

I could register all my classes under my own generic interface, IOptions or a common base class or something. But this doesn't prevent me from using a class outside of this interface as an IOptions<T> and further, I don't think the classes I register would be the same as the ones provided by the IOptions<T> registration, so it wouldn't even work.

I could just abandon IOptions<T> all together, but that means I have to expose my own Options interface for others to implement, which I can do, but I would rather not.


Solution

  • You could try following sample register to IOptions<object> :
    Console app, Package Microsoft.Extensions.Configuration Microsoft.Extensions.Configuration.Json Microsoft.Extensions.Configuration.Binder Microsoft.Extensions.Options ``
    Appsettings.json

    {
      "Option1": {
        "Name": "Tom"
      },
      "Option2": {
        "Age": 14
      }
    }
    

    option type

        public class Option1
        {
            public string Name { get; set; }
        }
        public class Option2 
        {
            public int Age { get; set; }
        }
    
    Console.WriteLine("Hello, World!");
    
    var builder = new ContainerBuilder();
    
    var config = new ConfigurationBuilder().AddJsonFile("appsettings.json").Build();
    builder.Register(c => Options.Create(config.GetSection("Option1").Get<Option1>())).As<IOptions<object>>();
    builder.Register(c => Options.Create(config.GetSection("Option2").Get<Option2>())).As<IOptions<object>>();
    
    var container = builder.Build();
    
    var optionsList = container.Resolve<IEnumerable<IOptions<object>>>();
    
    Console.ReadLine();
    

    Test result
    enter image description here