App Settings .Net Core

Question

I am trying to add an appsettings.json and followed a lot of tutorials and still can not do it.

I create appsettings.json

{
  "option1": "value1_from_json",

  "ConnectionStrings": {
    "DefaultConnection": "Server=,\\SQL2016DEV;Database=DBName;Trusted_Connection=True"
  },
  "Logging": {
    "IncludeScopes": false,
    "LogLevel": {
      "Default": "Warning"
    }
  }
}

Add my class:

public class MyOptions
{
    public string Option1 { get; set; }
}

public class ConnectionStringSettings
{
    public string DefaultConnection { get; set; }
}

then on my Startup.cs

public IConfiguration Configuration { get; set; }

public Startup(IHostingEnvironment env)
{
    var builder = new ConfigurationBuilder()
                        .SetBasePath(env.ContentRootPath)
                        .AddJsonFile("appsettings.json", optional: false, reloadOnChange: true)
                        .AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true);

    if (env.IsDevelopment())
    {
        builder.AddUserSecrets<Startup>();
    }

    builder.AddEnvironmentVariables();
    Configuration = builder.Build();
}

and :

public void ConfigureServices(IServiceCollection services)
{
    services.AddMvc();
    services.AddScoped<IDataService<Sale>, DataService<Sale>>();

    // add My services
    // Register the IConfiguration instance which MyOptions binds against.
    services.AddOptions();

    // Load the data from the 'root' of the json file
    services.Configure<MyOptions>(Configuration);

    // load the data from the 'ConnectionStrings' section of the json file
    var connStringSettings = Configuration.GetSection("ConnectionStrings");
    services.Configure<ConnectionStringSettings>(connStringSettings); 
}

and also injected the Dependency into the controller constructor.

public class ForecastApiController : Controller
{
    private IDataService<Sale> _SaleDataService;
    private readonly MyOptions _myOptions;

    public ForecastApiController(IDataService<Sale> service, IOptions<MyOptions> optionsAccessor)
    {
        _SaleDataService = service;
        _myOptions = optionsAccessor.Value;
        var valueOfOpt1 = _myOptions.Option1;
    }
}

EDITED: The problem is that I get Configuration underlined in red

 services.Configure<MyOptions>(Configuration); 

Error CS1503
Argument 2: cannot convert from 'Microsoft.Extensions.Configuration.IConfiguration' to 'System.Action Exercise.Models.MyOptions

I know there are similar questions explaining how to: ASP.NET Core MVC App Settings

but it doesn't work for me

Cheers

Highspirited

If it's underlined, hit ctrl+. and see what it tells you. Are you missing this line? IConfigurationRoot Configuration { get; } – Wharve

Yes, and now i get: Error CS1503 Argument 2: cannot convert from 'Microsoft.Extensions.Configuration.IConfiguration' to 'System.Action<OPSIexercise.Models.MyOptions>' – Highspirited

That's the sort of bug I see when I have a bracket or semicolon missing or extra. – Wharve

Sorry, I edited the question with the new error message regarding your comment – Highspirited

I think you have a similar bug (incorrect brackets) in your Controller. Also, how do you know that the History field isn't being set by the Configuration? You've set var window, but you don't use it in the code you're showing. – Wharve

Actually, I think I've got an idea. Try putting a subsection in your appsettings, like { "ConfigStrings": { "History" 14 } }. Then call services.Configure<MyOptions>(Configuration.GetSection("ConfigStrings")) – Wharve

@AleGarcia ConfigureServices is called before Configure You are building the Configuration too late in the startup class. The linked question is doing it in the class constructor. – Ministry

not sure but I copy the code from linked question I get the same error – Highspirited

You should build your config in the Startup constructor or even in Program.cs and then inject it into Startup. – Ballocks

Yes I have done it but still same error, i fact Im going to edit my question to include the constructor and the build. cheers – Highspirited

Is there a reason why you are using ASP.NET Core 1.x instead of 2.0? – Designed

Answer 1

Did you include the correct namespace?

using Microsoft.Extensions.DependencyInjection;

Also did you have a reference to?:

Microsoft.Extensions.Options.ConfigurationExtensions

In above Assembly we have:

public static IServiceCollection Configure<TOptions>(this IServiceCollection services, IConfiguration config) where TOptions : class;

Most probably you are using the extension method from Microsoft.Extensions.Options assembly (which is wrong)

public static IServiceCollection Configure<TOptions>(this IServiceCollection services, Action<TOptions> configureOptions) where TOptions : class;

Geanine

Ha! Also did you have a reference to?: Microsoft.Extensions.Options.ConfigurationExtensions – Highspirited

Just a tip: Use the Meta package in Future at least for developement. It makes our life so much easier ;) learn.microsoft.com/en-us/aspnet/core/fundamentals/metapackage – Geanine

Answer 2

Make sure that you imported everything that is necessary and have the required packages installed. Then you can do the following

services.Configure<MyOptions>(options => Configuration.GetSection("options1").Bind(options)); 

this will cause the options to be updated at runtime whenever you change the appssettings programatically.

Necrophilism