Published 2nd sept 2020

I like this approach, site settings thru Dependency Injection (DI). Im fully aware that this subject is nothing new, and EMVP collegues have been blogged about this for ages.

Arild: https://www.epinova.se/nyheter-och-blogg/utvecklarbloggen/2016/configuration-options-for-episerver-sites/
Maris: https://marisks.net/2020/03/31/managing-settings-in-episerver-project-3/
Mathias: https://blog.mathiaskunto.com/2016/09/29/easy-way-to-manage-global-settings-in-multilanguage-episerver-website/
Linus: https://github.com/LinusEkstrom/AddOn.Episerver.Settings

However, none are using Interface and DI to locate the settings (except Linus’ addon, but thats another approach).

Usage

Example 1 – preferable

public FeatureFlagService(ISiteSettings siteSettings)
{
    _siteSettings = siteSettings;
} 

Example 2 – get StartPage as ISiteSettings

siteSettings = IContentLoader.Get<ISiteSettings>(SiteDefinition.Current.StartPage, LanguageSelector.AutoDetect());

        //Rule two, from site settings
        if (siteSettings.NewFeatureEnabled)
            _flag1 = siteSettings.NewFeatureEnabled;

Example 3, multiple ISiteSettings in one site

 var startPage = repository.GetClosest(currentPage); 

Make an Interface ISiteSettings

 namespace AlloyTemplates.Business
{
    public interface ISiteSettings : IContent
    {
        bool NewFeatureEnabled { get; set; }
    }
}

Add your settings properties into this Interface

SiteSetting needs to derive from IContent since you later want to use the contentLoader to load ISiteSettings

Implement Interface as a Partial class

What you need is to put key word “partial” into both object implementation, important to use same class name in same namespace.

[ContentType(GUID = "x")]
public partial class StartPage : SitePageData, IContent

and

     public partial class StartPage : ISiteSettings
    {
        [Display(GroupName = Global.GroupNames.SiteSettings, Order = 1)]
        public virtual bool NewFeatureEnabled { get; set; }
    } 

Note: It is the StartPage that is derived from PageData that implements IContent and not the StartPage.ISiteSettings

Register ISiteSettings to StructureMap with Registry

    public class SiteSettingsRegistry : Registry
    {
        /// Exposed as internal to enable usage from test class library
        internal static Func LangSelector = LanguageSelector.AutoDetect;

        public SiteSettingsRegistry()
        {
            For().HybridHttpOrThreadLocalScoped().Use(context => GetSiteSettings(context, LangSelector()));
        }

        private static ISiteSettings GetSiteSettings(IContext context, LanguageSelector languageSelector)
        {
            var contentLoader = context.GetInstance();
            return contentLoader.Get(ContentReference.StartPage, languageSelector);
        }
    }

The Registry will be scanned and configured if you configure StructureMap with a IConfigurableModule like this:

     [InitializableModule]
    public class DependencyResolverInitialization : IConfigurableModule
    {
        public void ConfigureContainer(ServiceConfigurationContext context)
        {
            //Implementations for custom interfaces can be registered here.

            context.StructureMap().Configure(
                x =>
                {
                    x.Scan(y =>
                    {
                        y.TheCallingAssembly();
                        y.LookForRegistries();
                        y.WithDefaultConventions();
                    });
                });
        }
    } 

Multisite scenario

Yes! by using ContentReference.StartPage in registry or SiteDefinition.Current.StartPage it will contextualy return the right settings.

Note: remember to set * in website management i Epi Admin to assign the default website if no HttpContext exists (in scheduled jobs ContentReference.StartPage will return the default website startpage if * is configured)

About the author

Luc Gosso
– Independent Senior Web Developer
working with Azure and Episerver

Twitter: @LucGosso
LinkedIn: linkedin.com/in/luc-gosso/
Github: github.com/lucgosso