Moved files to core to enable reuse + use them

src/Umbraco.Core/Events/CancelableEnumerableObjectNotification.cs

@@ -2,9 +2,8 @@
 // See LICENSE for more details.
 
 using System.Collections.Generic;
-using Umbraco.Cms.Core.Events;
 
-namespace Umbraco.Cms.Infrastructure.Services.Notifications
+namespace Umbraco.Cms.Core.Events
 {
     public abstract class CancelableEnumerableObjectNotification<T> : CancelableObjectNotification<IEnumerable<T>>
     {

src/Umbraco.Core/Events/CancelableObjectNotification.cs

@@ -1,9 +1,7 @@
 // Copyright (c) Umbraco.
 // See LICENSE for more details.
 
-using Umbraco.Cms.Core.Events;
-
-namespace Umbraco.Cms.Infrastructure.Services.Notifications
+namespace Umbraco.Cms.Core.Events
 {
     public abstract class CancelableObjectNotification<T> : ObjectNotification<T>, ICancelableNotification where T : class
     {

src/Umbraco.Core/Events/CopiedNotification.cs

@@ -1,9 +1,7 @@
 // Copyright (c) Umbraco.
 // See LICENSE for more details.
 
-using Umbraco.Cms.Core.Events;
-
-namespace Umbraco.Cms.Infrastructure.Services.Notifications
+namespace Umbraco.Cms.Core.Events
 {
     public abstract class CopiedNotification<T> : ObjectNotification<T> where T : class
     {

src/Umbraco.Core/Events/CopyingNotification.cs

@@ -1,9 +1,7 @@
 // Copyright (c) Umbraco.
 // See LICENSE for more details.
 
-using Umbraco.Cms.Core.Events;
-
-namespace Umbraco.Cms.Infrastructure.Services.Notifications
+namespace Umbraco.Cms.Core.Events
 {
     public abstract class CopyingNotification<T> : CancelableObjectNotification<T> where T : class
     {

src/Umbraco.Core/Events/DeletedNotification.cs

@@ -2,9 +2,8 @@
 // See LICENSE for more details.
 
 using System.Collections.Generic;
-using Umbraco.Cms.Core.Events;
 
-namespace Umbraco.Cms.Infrastructure.Services.Notifications
+namespace Umbraco.Cms.Core.Events
 {
     public abstract class DeletedNotification<T> : EnumerableObjectNotification<T>
     {

src/Umbraco.Core/Events/EnumerableObjectNotification.cs

@@ -2,9 +2,8 @@
 // See LICENSE for more details.
 
 using System.Collections.Generic;
-using Umbraco.Cms.Core.Events;
 
-namespace Umbraco.Cms.Infrastructure.Services.Notifications
+namespace Umbraco.Cms.Core.Events
 {
     public abstract class EnumerableObjectNotification<T> : ObjectNotification<IEnumerable<T>>
     {

src/Umbraco.Core/Events/EventAggregator.cs

@@ -55,6 +55,30 @@ namespace Umbraco.Cms.Core.Events
             PublishNotification(notification);
             Task.WaitAll(PublishNotificationAsync(notification));
         }
+
+        public bool PublishCancelable<TCancelableNotification>(TCancelableNotification notification)
+            where TCancelableNotification : ICancelableNotification
+        {
+            if (notification == null)
+            {
+                throw new ArgumentNullException(nameof(notification));
+            }
+
+            Publish(notification);
+            return notification.Cancel;
+        }
+
+        public async Task<bool> PublishCancelableAsync<TCancelableNotification>(TCancelableNotification notification)
+            where TCancelableNotification : ICancelableNotification
+        {
+            if (notification == null)
+            {
+                throw new ArgumentNullException(nameof(notification));
+            }
+
+            await PublishAsync(notification);
+            return notification.Cancel;
+        }
     }
 
     /// <summary>

src/Umbraco.Core/Events/IEventAggregator.cs

@@ -29,5 +29,23 @@ namespace Umbraco.Cms.Core.Events
         /// <param name="notification">The notification object.</param>
         void Publish<TNotification>(TNotification notification)
             where TNotification : INotification;
+
+        /// <summary>
+        /// Publishes a cancelable notification to the notification subscribers
+        /// </summary>
+        /// <typeparam name="TNotification">The type of notification being handled.</typeparam>
+        /// <param name="notification"></param>
+        /// <returns>True if the notification was cancelled by a subscriber, false otherwise</returns>
+        bool PublishCancelable<TCancelableNotification>(TCancelableNotification notification)
+            where TCancelableNotification : ICancelableNotification;
+
+        /// <summary>
+        /// Publishes a cancelable notification async to the notification subscribers
+        /// </summary>
+        /// <typeparam name="TNotification">The type of notification being handled.</typeparam>
+        /// <param name="notification"></param>
+        /// <returns>True if the notification was cancelled by a subscriber, false otherwise</returns>
+        Task<bool> PublishCancelableAsync<TCancelableNotification>(TCancelableNotification notification)
+            where TCancelableNotification : ICancelableNotification;
     }
 }

src/Umbraco.Core/Events/ImportedPackageNotification.cs

@@ -3,7 +3,7 @@ using Umbraco.Cms.Core.Packaging;
 
 namespace Umbraco.Cms.Core.Events
 {
-    public class ImportedPackageNotification : INotification
+    public class ImportedPackageNotification : StatefulNotification
     {
 
         public ImportedPackageNotification(InstallationSummary installationSummary, IPackageInfo packageMetaData)

src/Umbraco.Core/Events/ImportingPackageNotification.cs

@@ -2,7 +2,7 @@ using Umbraco.Cms.Core.Models.Packaging;
 
 namespace Umbraco.Cms.Core.Events
 {
-    public class ImportingPackageNotification : ICancelableNotification
+    public class ImportingPackageNotification : StatefulNotification, ICancelableNotification
     {
         public ImportingPackageNotification(string packageName, IPackageInfo packageMetaData)
         {

src/Umbraco.Core/Events/MovedNotification.cs

@@ -2,9 +2,8 @@
 // See LICENSE for more details.
 
 using System.Collections.Generic;
-using Umbraco.Cms.Core.Events;
 
-namespace Umbraco.Cms.Infrastructure.Services.Notifications
+namespace Umbraco.Cms.Core.Events
 {
     public abstract class MovedNotification<T> : ObjectNotification<IEnumerable<MoveEventInfo<T>>>
     {

src/Umbraco.Core/Events/MovingNotification.cs

@@ -2,9 +2,8 @@
 // See LICENSE for more details.
 
 using System.Collections.Generic;
-using Umbraco.Cms.Core.Events;
 
-namespace Umbraco.Cms.Infrastructure.Services.Notifications
+namespace Umbraco.Cms.Core.Events
 {
     public abstract class MovingNotification<T> : CancelableObjectNotification<IEnumerable<MoveEventInfo<T>>>
     {

src/Umbraco.Core/Events/ObjectNotification.cs

@@ -1,9 +1,7 @@
 // Copyright (c) Umbraco.
 // See LICENSE for more details.
 
-using Umbraco.Cms.Core.Events;
-
-namespace Umbraco.Cms.Infrastructure.Services.Notifications
+namespace Umbraco.Cms.Core.Events
 {
     public abstract class ObjectNotification<T> : StatefulNotification where T : class
     {

src/Umbraco.Core/Events/RolledBackNotification.cs

@@ -1,9 +1,7 @@
 // Copyright (c) Umbraco.
 // See LICENSE for more details.
 
-using Umbraco.Cms.Core.Events;
-
-namespace Umbraco.Cms.Infrastructure.Services.Notifications
+namespace Umbraco.Cms.Core.Events
 {
     public abstract class RolledBackNotification<T> : ObjectNotification<T> where T : class
     {

src/Umbraco.Core/Events/RollingBackNotification.cs

@@ -1,9 +1,7 @@
 // Copyright (c) Umbraco.
 // See LICENSE for more details.
 
-using Umbraco.Cms.Core.Events;
-
-namespace Umbraco.Cms.Infrastructure.Services.Notifications
+namespace Umbraco.Cms.Core.Events
 {
     public abstract class RollingBackNotification<T> : CancelableObjectNotification<T> where T : class
     {

src/Umbraco.Core/Events/SavedNotification.cs

@@ -2,9 +2,8 @@
 // See LICENSE for more details.
 
 using System.Collections.Generic;
-using Umbraco.Cms.Core.Events;
 
-namespace Umbraco.Cms.Infrastructure.Services.Notifications
+namespace Umbraco.Cms.Core.Events
 {
     public abstract class SavedNotification<T> : EnumerableObjectNotification<T>
     {

src/Umbraco.Core/Events/SavingNotification.cs

@@ -2,9 +2,8 @@
 // See LICENSE for more details.
 
 using System.Collections.Generic;
-using Umbraco.Cms.Core.Events;
 
-namespace Umbraco.Cms.Infrastructure.Services.Notifications
+namespace Umbraco.Cms.Core.Events
 {
     public abstract class SavingNotification<T> : CancelableEnumerableObjectNotification<T>
     {

src/Umbraco.Core/Events/SortedNotification.cs

@@ -2,9 +2,8 @@
 // See LICENSE for more details.
 
 using System.Collections.Generic;
-using Umbraco.Cms.Core.Events;
 
-namespace Umbraco.Cms.Infrastructure.Services.Notifications
+namespace Umbraco.Cms.Core.Events
 {
     public abstract class SortedNotification<T> : EnumerableObjectNotification<T>
     {

src/Umbraco.Core/Events/SortingNotification.cs

@@ -2,9 +2,8 @@
 // See LICENSE for more details.
 
 using System.Collections.Generic;
-using Umbraco.Cms.Core.Events;
 
-namespace Umbraco.Cms.Infrastructure.Services.Notifications
+namespace Umbraco.Cms.Core.Events
 {
     public abstract class SortingNotification<T> : CancelableEnumerableObjectNotification<T>
     {

src/Umbraco.Core/Events/StatefulNotification.cs

@@ -1,9 +1,8 @@
 // Copyright (c) Umbraco.
 
 using System.Collections.Generic;
-using Umbraco.Cms.Core.Events;
 
-namespace Umbraco.Cms.Infrastructure.Services.Notifications
+namespace Umbraco.Cms.Core.Events
 {
     public abstract class StatefulNotification : IStatefulNotification
     {

src/Umbraco.Core/Events/UnattendedInstallNotification.cs

@@ -1,7 +1,4 @@
-using System;
-using Umbraco.Cms.Core.Events;
-
-namespace Umbraco.Core.Events
+namespace Umbraco.Cms.Core.Events
 {
     /// <summary>
     /// Used to notify that an Unattended install has completed

src/Umbraco.Infrastructure/RuntimeState.cs

@@ -11,7 +11,6 @@ using Umbraco.Cms.Core.Services;
 using Umbraco.Cms.Infrastructure.Migrations.Install;
 using Umbraco.Cms.Infrastructure.Migrations.Upgrade;
 using Umbraco.Cms.Infrastructure.Persistence;
-using Umbraco.Core.Events;
 
 namespace Umbraco.Cms.Core
 {

src/Umbraco.Infrastructure/Services/Implement/PackagingService.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
@@ -120,13 +120,12 @@ namespace Umbraco.Cms.Core.Services.Implement
             var compiledPackage = GetCompiledPackageInfo(packageFile);
             if (compiledPackage == null) throw new InvalidOperationException("Could not read the package file " + packageFile);
 
-            // Trigger the Importing Package Notification
-            var notification = new ImportingPackageNotification(packageFile.Name, compiledPackage);
-            _eventAggregator.Publish(notification);
-
-            // Stop execution if event/user is cancelling it
-            if (notification.Cancel)
+            // Trigger the Importing Package Notification and stop execution if event/user is cancelling it
+            var importingPackageNotification = new ImportingPackageNotification(packageFile.Name, compiledPackage);
+            if (_eventAggregator.PublishCancelable(importingPackageNotification))
+            {
                 return new InstallationSummary { MetaData = compiledPackage };
+            }
 
             var summary = _packageInstallation.InstallPackageData(packageDefinition, compiledPackage, userId);
 
@@ -135,7 +134,7 @@ namespace Umbraco.Cms.Core.Services.Implement
             _auditService.Add(AuditType.PackagerInstall, userId, -1, "Package", $"Package data installed for package '{compiledPackage.Name}'.");
 
             // trigger the ImportedPackage event
-            _eventAggregator.Publish(new ImportedPackageNotification(summary, compiledPackage));
+            _eventAggregator.Publish(new ImportedPackageNotification(summary, compiledPackage).WithStateFrom(importingPackageNotification));
 
             return summary;
         }

src/Umbraco.Infrastructure/Services/Notifications/ContentNotificationExtensions.cs

@@ -1,6 +1,7 @@
 // Copyright (c) Umbraco.
 // See LICENSE for more details.
 
+using Umbraco.Cms.Core.Events;
 using Umbraco.Cms.Core.Models;
 
 namespace Umbraco.Cms.Infrastructure.Services.Notifications

src/Umbraco.Web.Common/DependencyInjection/UmbracoBuilderExtensions.cs

@@ -55,8 +55,6 @@ using Umbraco.Cms.Web.Common.Routing;
 using Umbraco.Cms.Web.Common.Security;
 using Umbraco.Cms.Web.Common.Templates;
 using Umbraco.Cms.Web.Common.UmbracoContext;
-using Umbraco.Core.Events;
-using static Umbraco.Cms.Core.Cache.HttpContextRequestAppCache;
 using IHostingEnvironment = Umbraco.Cms.Core.Hosting.IHostingEnvironment;
 
 namespace Umbraco.Extensions

src/Umbraco.Web.Common/Install/CreateUnattendedUserNotificationHandler.cs

@@ -9,7 +9,6 @@ using Umbraco.Cms.Core.Events;
 using Umbraco.Cms.Core.Models.Membership;
 using Umbraco.Cms.Core.Security;
 using Umbraco.Cms.Core.Services;
-using Umbraco.Core.Events;
 using Umbraco.Extensions;
 
 namespace Umbraco.Cms.Web.Common.Install