Whenever you need to modify an entity that Umbraco stores in the database, there are service APIs available to help you. This means that you can create, update and delete any of the core Umbraco entities directly from your custom code.
Accessing the Umbraco services
Services are typically defined using interfaces. Umbraco has them in the Umbraco.Cms.Core.Services namespace, while the specific implementations can be found under the Umbraco.Cms.Core.Services.Implement namespace. To use the service APIs you must first access them. Owing to the built-in dependency injection (DI) in ASP.NET Core, configured services are made available throughout Umbraco's codebase. This can be achieved via injecting the specific service you require - the service type or an interface.
Access via a Controller
If you are accessing Umbraco services inside your own controller class, you can add the Umbraco services that you need as constructor parameters. An instance of every service will be provided at runtime from the service container. By saving each one to a local field, you can make use of them within the scope of your class:
public class CustomController
{
private readonly IContentService _contentService;
public ContentController(IContentService contentService)
{
_contentService = contentService;
}
public ActionResult PerformAction()
{
var someContent = _contentService.GetById(1234);
}
}
Access via a Razor View Template
Inside a Razor View template, you can make use of a service injection into a view using the @inject directive. It works similarly to adding a property to the view, and populating the property using DI:
If we wish to subscribe to notifications on one of the services, we'd create a Composer C# class, where you will add a custom NotificationHandler. In this custom NotificationHandler we would inject the service we need into the public constructor of the class and Umbraco's. The underlying dependency injection framework will do the rest.
In this example we will wire up to the ContentService 'Saved' event. We will create a new folder in the Media section whenever a new LandingPage is created in the content section to store associated media. Therefore we will need the MediaService available to create the new folder.
public class CustomComposer : IComposer
{
public void Compose(IUmbracoBuilder builder)
{
builder.AddNotificationHandler<ContentSavedNotification, CustomNotificationHandler>();
}
}
using System.Linq;
using Umbraco.Cms.Core;
using Umbraco.Cms.Core.Events;
using Umbraco.Cms.Core.Models;
using Umbraco.Cms.Core.Notifications;
using Umbraco.Cms.Core.Services;
namespace Umbraco.Cms.Core.Events;
public class CustomNotificationHandler : INotificationHandler<ContentSavedNotification>
{
// access to the MediaService by injection
private readonly IMediaService _mediaService;
private readonly IRuntimeState _runtimeState;
public CustomNotificationHandler(IMediaService mediaService, IRuntimeState runtimeState)
{
_mediaService = mediaService;
_runtimeState = runtimeState;
}
public void Handle(ContentSavedNotification notification)
{
if (_runtimeState.Level != RuntimeLevel.Run)
{
return;
}
foreach (var contentItem in notification.SavedEntities)
{
// if this is a new landing page create a folder for associated media in the media section
if (contentItem.ContentType.Alias == "landingPage")
{
// we have injected in the mediaService in the constructor for the component see above.
bool hasExistingFolder = _mediaService.GetByLevel(1).Any(f => f.Name == contentItem.Name);
if (!hasExistingFolder)
{
// let's create one (-1 indicates the root of the media section)
IMedia newFolder = _mediaService.CreateMedia(contentItem.Name, -1, "Folder");
_mediaService.Save(newFolder);
}
}
}
}
}
Custom Class example
When you're creating your own class, in order to make use of the dependency injection framework, you need register the ICustomNewsArticleService service with the type CustomNewsArticleService. The AddScoped() method registers the service with the lifetime of a single request.
There are different ways that you can achieve the same outcome:
Another approach is to create an extension method to IUmbracoBuilder and add it to the startup pipeline.
using Microsoft.Extensions.DependencyInjection;
using Umbraco.Cms.Core.DependencyInjection;
namespace DefaultNamespace;
public static class UmbracoBuilderServiceExtensions
{
public static IUmbracoBuilder AddCustomServices(this IUmbracoBuilder builder)
{
builder.Services.AddScoped<ICustomNewsArticleService, CustomNewsArticleService>();
return builder;
}
}
When creating Umbraco packages you don't have access to the Startup class, therefore it's recommended to use a IComposer instead. A Composer gives you access to the IUmbracoBuilder.
If you don't have access to the Startup class
public class CustomComposer : IComposer
{
public void Compose(IUmbracoBuilder builder)
{
builder.Services.AddScoped<ICustomNewsArticleService, CustomNewsArticleService>();
}
}
Then your custom class eg. CustomNewsArticleService can take advantage of the same injection to access services eg:
using System.Linq;
using Microsoft.Extensions.Logging;
using Umbraco.Cms.Core.Models.PublishedContent;
using Umbraco.Cms.Core.PublishedCache;
using Umbraco.Cms.Core.Services;
using Umbraco.Cms.Core.Web;
namespace Umbraco.Cms.Infrastructure.Services.Implement;
public class CustomNewsArticleService: ICustomNewsArticleService
{
private readonly IMediaService _mediaService;
private readonly ILogger<CustomNewsArticleService> _logger;
private readonly IUmbracoContextFactory _contextFactory;
public CustomNewsArticleService(ILogger<CustomNewsArticleService> logger, IUmbracoContextFactory contextFactory, IMediaService mediaService)
{
_logger = logger;
_contextFactory = contextFactory;
_mediaService = mediaService;
}
public void DoSomethingWithNewsArticles()
{
using (var contextReference = _contextFactory.EnsureUmbracoContext())
{
IPublishedContentCache contentCache = contextReference.UmbracoContext.Content;
IPublishedContent newsSection = contentCache.GetAtRoot().FirstOrDefault().Children.FirstOrDefault(f => f.ContentType.Alias == "newsSection");
if (newsSection == null)
{
_logger.LogDebug("News Section Not Found");
}
}
// etc
}
}
Services available
There is full API coverage of all Umbraco core entities:
