NinjaSettings

Simple Dynamic Wrapper around the .NET web.config app settings that gives strongly typed access to app settings. Easily mockable and extensible.

Quick Example

Add some ordinary old app settings to your web.config file.

  <appSettings>
    <add key="SomeIntegerList" value="50,20,10,100"/>
    <add key="SomeTestEnum" value="Bar"/>
    <add key="SomeDateValue" value ="11/10/2013"/>
    <add key="SomeStringArray" value ="bing,bam,  boom, buzz"/> 
  </appSettings>

Create an interface with property names matching the app settings keys, and the desired types you'd like the values converted to when you reference them in your application.

public interface IAppSettings
{
    List<int> SomeIntegerList { get; }
    TestEnum SomeTestEnum { get; }
    DateTime SomeDateValue { get; } 
    string[] SomeStringArray { get;  }
}

Register your interface with your favourite IOC container, using the NinjaSettings wrapper.

protected void Application_Start()
{
    //Autofac Setup
    var builder = new ContainerBuilder();
    builder.Register(c => new NinjaSettings<IAppSettings>().Settings)
        .As<IAppSettings>().SingleInstance();
}

Simply inject your app settings into your classes as a dependency on your interface. Access your settings as a strongly typed object with full intellisense.

public class MyService
{
    private readonly IAppSettings _appSettings;

    public MyService(IAppSettings appSettings)
    {
        _appSettings = appSettings;
    }

    public void DoSomeStuff()
    {
        foreach (var s in _appSettings.SomeStringArray)
        {
            // Do Something
        }
    }
} 

No need for your web.config or the NinjaSettings wrapper for your tests. Just Mock up an instance of your interface and pass that in to your class under test.

[Test]
public void GivenMyServiceDoesSomethingThenItShouldGoBeep()
{
    var mockAppSettings = Substitute.For<IAppSettings>();
    mockAppSettings.SomeStringArray.Returns(new[] {"foo", "bar", "baz"});

    var classUnderTest = new MyService(mockAppSettings);

    classUnderTest.DoSomeStuff();

    Assert.IsTrue(classUnderTest.HasGoneBeep);
}

Ok, so whats this about being extensible

The NinjaSettings wrapper can be extended to parse just about any type. Out of the box it handles converting string settings to scalar values, collections of scalar values, Enums and DateTimes. Just about any conversion from the original string can be handled by creating an implementing a simple value converter.

public interface ISettingValueConverter
{
    bool CanConvert(Type type);

    object Convert(string fromValue, Type convertToType);
}

By default, NinjaSettings wraps the <AppSettings> section of the ASP.NET web.config file, but can easily be used to wrap any key-value store (resource (resx) files, cache entries, string dictionaries, look-up tables in databases) by implementing the following super simple Interface.

public interface ISettingsRepository
{
    string Get(string settingName);
}

To extend NinjaSettings, just pass your ISettingsRepository and/or an IEnumerable<ISettingValueConverter> into the NinjaSettings constructor.

How do I get it

Clone this repository and build it yourself, or get it from Nuget

Install-Package NinjaSettings