# Umbraco Application Lifetime Notifications

Umbraco application lifetime notifications are published for the starting, started, stopping, and stopped events of the Umbraco runtime. These events implement the `IUmbracoApplicationLifetimeNotification` interface that contains a single `IsRestarting` property.

An Umbraco application is restarted after an install or upgrade has been completed. You can use this property to prevent running code twice: on initial boot and restart. To prevent running code when the application is in the install or upgrade state, inject an `IRuntimeState` instance in your notification and inspect the `Level` property instead.

## Usage

Example usage of the UmbracoApplicationLifetime notifications:

```csharp
using Microsoft.Extensions.Logging;
using Umbraco.Cms.Core.Composing;
using Umbraco.Cms.Core.Events;
using Umbraco.Cms.Core.DependencyInjection;
using Umbraco.Cms.Core.Notifications;

public class UmbracoApplicationNotificationComposer : IComposer
{
    public void Compose(IUmbracoBuilder builder)
    {
        builder.AddNotificationHandler<UmbracoApplicationStartingNotification, UmbracoApplicationNotificationHandler>();
        builder.AddNotificationHandler<UmbracoApplicationStartedNotification, UmbracoApplicationNotificationHandler>();
        builder.AddNotificationHandler<UmbracoApplicationStoppingNotification, UmbracoApplicationNotificationHandler>();
        builder.AddNotificationHandler<UmbracoApplicationStoppedNotification, UmbracoApplicationNotificationHandler>();
    }
}

public class UmbracoApplicationNotificationHandler : INotificationHandler<UmbracoApplicationStartingNotification>, INotificationHandler<UmbracoApplicationStartedNotification>, INotificationHandler<UmbracoApplicationStoppingNotification>, INotificationHandler<UmbracoApplicationStoppedNotification>
{
    private readonly ILogger _logger;

    public UmbracoApplicationNotificationHandler(ILogger<UmbracoApplicationNotificationHandler> logger) => _logger = logger;

    public void Handle(UmbracoApplicationStartingNotification notification) => Log(notification, notification.IsRestarting);

    public void Handle(UmbracoApplicationStartedNotification notification) => Log(notification, notification.IsRestarting);

    public void Handle(UmbracoApplicationStoppingNotification notification) => Log(notification, notification.IsRestarting);

    public void Handle(UmbracoApplicationStoppedNotification notification) => Log(notification, notification.IsRestarting);

    private void Log(INotification notification, bool isRestarting) => _logger.LogInformation("{Type} - {IsRestarting}", notification.GetType().Name, isRestarting);
}
```