How to Enable Feature Toggle in .Net Core Using Feature Toggle Nuget Package?

Question

Below are the changes which I did it in my application. Added FeatureToggle package in the code. And Created New Printing Class(Sample class only for) Extending SimpleFeatureToggle.

using FeatureToggle;

namespace AspDotNetCoreExample.Models
{
    public class Printing : SimpleFeatureToggle {}
}

appSettings.json added featureToggle Key and it is set as true. So the Printing class will read it and enable feature toggling.

    {
  "FeatureToggle": {
    "Printing": "true"
  }
  }

** Startup.cs Registered my Printing Service in ConfigureServices Method. I have passed the configuration file(appSettings.json) into Printing class.

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

    public IConfigurationRoot Configuration { get; }

    public void ConfigureServices(IServiceCollection services)
    {
        // Set provider config so file is read from content root path
        var provider = new AppSettingsProvider { Configuration = Configuration };
        services.Configure<AppSettings(Configuration.GetSection("AppSettings"));
        services.AddSingleton(new Printing { ToggleValueProvider = provider });       
        services.AddTransient<IMapper, Mapper>();
        // Add framework services.
        services.AddMvc();
    }

// In Mapper Class, to check the feature toggle is enabled or not and to enable the features.

namespace STAR.Marketing.Portal.Web
{
    public class Mapper: Mapper
    {
        private readonly Printing _print;

        public Mapper(Printing print) //Dependency Injection to get Printing
        {
            _print = print;
        }
        public string Enabled()
        {
            return _print.FeatureEnabled;   // To check the feature is enabled but getting the Error System.FileIOException
        }
    }
}

What are the mistakes I have done in the above code? Why I am getting this error in my code, System.FileIOException.?

score 0 · Answer 1 · answered Dec 20 '17 at 15:20

I would suggest you include the error next time you are trying to get help. My guess is if you just created a project it is likely that the appsetting.json file is not in the bin folder. You can investigate this, or you can just right click on the appsettings.json file, select properties, and change the "Copy to Output Directory" to "Always Copy".

How to Enable Feature Toggle in .Net Core Using Feature Toggle Nuget Package?

1 Answers1