Fixed: Tracked Download Cache Keeps Deleted Albums (#811)

* Fixed: Tracked Download Cache Deleted Albums

* Add a test

src/NzbDrone.Core.Test/Download/TrackedDownloads/TrackedDownloadServiceFixture.cs

@@ -11,6 +11,7 @@ using NzbDrone.Core.Test.Framework;
 using NzbDrone.Core.Music;
 using NzbDrone.Core.Indexers;
 using System.Linq;
+using NzbDrone.Core.Music.Events;
 
 namespace NzbDrone.Core.Test.Download.TrackedDownloads
 {
@@ -72,5 +73,54 @@ namespace NzbDrone.Core.Test.Download.TrackedDownloads
             trackedDownload.RemoteAlbum.Albums.First().Id.Should().Be(4);
         }
 
+        [Test]
+        public void should_unmap_tracked_download_if_album_deleted()
+        {
+            GivenDownloadHistory();
+
+            var remoteAlbum = new RemoteAlbum
+            {
+                Artist = new Artist() { Id = 5 },
+                Albums = new List<Album> { new Album { Id = 4 } },
+                ParsedAlbumInfo = new ParsedAlbumInfo()
+                {
+                    AlbumTitle = "Audio Album",
+                    ArtistName = "Audio Artist"
+                }
+            };
+
+            Mocker.GetMock<IParsingService>()
+                  .Setup(s => s.Map(It.Is<ParsedAlbumInfo>(i => i.AlbumTitle == "Audio Album" && i.ArtistName == "Audio Artist"), It.IsAny<int>(), It.IsAny<IEnumerable<int>>()))
+                  .Returns(remoteAlbum);
+
+            var client = new DownloadClientDefinition()
+            {
+                Id = 1,
+                Protocol = DownloadProtocol.Torrent
+            };
+
+            var item = new DownloadClientItem()
+            {
+                Title = "Audio Artist - Audio Album [2018 - FLAC]",
+                DownloadId = "35238",
+            };
+
+            // get a tracked download in place
+            var trackedDownload = Subject.TrackDownload(client, item);
+            Subject.GetTrackedDownloads().Should().HaveCount(1);
+
+            // simulate deletion - album no longer maps
+            Mocker.GetMock<IParsingService>()
+                .Setup(s => s.Map(It.Is<ParsedAlbumInfo>(i => i.AlbumTitle == "Audio Album" && i.ArtistName == "Audio Artist"), It.IsAny<int>(), It.IsAny<IEnumerable<int>>()))
+                .Returns(default(RemoteAlbum));
+
+            // handle deletion event
+            Subject.Handle(new AlbumDeletedEvent(remoteAlbum.Albums.First(), false));
+
+            // verify download has null remote album
+            var trackedDownloads = Subject.GetTrackedDownloads();
+            trackedDownloads.Should().HaveCount(1);
+            trackedDownloads.First().RemoteAlbum.Should().BeNull();
+        }
     }
 }

src/NzbDrone.Core/Download/TrackedDownloads/TrackedDownloadService.cs

@@ -9,10 +9,11 @@ using NzbDrone.Core.Messaging.Events;
 using NzbDrone.Core.Music;
 using NzbDrone.Core.Parser;
 using NzbDrone.Common.Serializer;
+using NzbDrone.Core.Music.Events;
 
 namespace NzbDrone.Core.Download.TrackedDownloads
 {
-    public interface ITrackedDownloadService
+    public interface ITrackedDownloadService : IHandle<AlbumDeletedEvent>
     {
         TrackedDownload Find(string downloadId);
         void StopTracking(string downloadId);
@@ -48,6 +49,24 @@ namespace NzbDrone.Core.Download.TrackedDownloads
             return _cache.Find(downloadId);
         }
 
+        public void UpdateAlbumCache(int albumId)
+        {
+            var updateCacheItems = _cache.Values.Where(x => x.RemoteAlbum.Albums.Any(a => a.Id == albumId)).ToList();
+
+            foreach (var item in updateCacheItems)
+            {
+                var parsedAlbumInfo = Parser.Parser.ParseAlbumTitle(item.DownloadItem.Title);
+                item.RemoteAlbum = null;
+
+                if (parsedAlbumInfo != null)
+                {
+                    item.RemoteAlbum = _parsingService.Map(parsedAlbumInfo);
+                }
+            }
+
+            _eventAggregator.PublishEvent(new TrackedDownloadRefreshedEvent(GetTrackedDownloads()));
+        }
+
         public void StopTracking(string downloadId)
         {
             var trackedDownload = _cache.Find(downloadId);
@@ -224,5 +243,11 @@ namespace NzbDrone.Core.Download.TrackedDownloads
 
             return TrackedDownloadStage.Downloading;
         }
+
+        public void Handle(AlbumDeletedEvent message)
+        {
+            UpdateAlbumCache(message.Album.Id);
+        }
     }
 }
+