Backport pull request #18007 from jellyfin/release-12.z

Preserve library items when directory enumeration fails

Original-merge: 63def185b199c5afded850b8eb5667276bc864f9

Merged-by: crobibero <cody@robibe.ro>

Backported-by: Cody Robibero <cody@robibe.ro>

2 files changed, 64 insertions, 2 deletions

diff --git a/MediaBrowser.Controller/Entities/Folder.cs b/MediaBrowser.Controller/Entities/Folder.cs
index 25e19c8351..dae4612aa1 100644
--- a/MediaBrowser.Controller/Entities/Folder.cs
+++ b/MediaBrowser.Controller/Entities/Folder.cs
@@ -429,19 +429,23 @@ namespace MediaBrowser.Controller.Entities
 
             if (IsFileProtocol)
             {
-                IEnumerable<BaseItem> nonCachedChildren = [];
+                IEnumerable<BaseItem> nonCachedChildren;
 
                 try
                 {
-                    nonCachedChildren = GetNonCachedChildren(directoryService);
+                    // Finish enumeration before mutating the library. An I/O failure, including
+                    // one partway through a lazy enumeration, must not look like removed files.
+                    nonCachedChildren = GetNonCachedChildren(directoryService).ToArray();
                 }
                 catch (IOException ex)
                 {
                     Logger.LogError(ex, "Error retrieving children from file system");
+                    return;
                 }
                 catch (SecurityException ex)
                 {
                     Logger.LogError(ex, "Error retrieving children from file system");
+                    return;
                 }
                 catch (Exception ex)
                 {
diff --git a/tests/Jellyfin.Controller.Tests/Entities/BaseItemTests.cs b/tests/Jellyfin.Controller.Tests/Entities/BaseItemTests.cs
index 588f9d5530..e072bccb82 100644
--- a/tests/Jellyfin.Controller.Tests/Entities/BaseItemTests.cs
+++ b/tests/Jellyfin.Controller.Tests/Entities/BaseItemTests.cs
@@ -30,6 +30,43 @@ namespace Jellyfin.Controller.Tests.Entities;
 [Collection("LibraryManagerTests")]
 public class BaseItemTests
 {
+    [Theory]
+    [InlineData(false, false)]
+    [InlineData(true, false)]
+    [InlineData(false, true)]
+    [InlineData(true, true)]
+    public async Task ValidateChildren_FailedEnumeration_DoesNotReconcileOrDeleteChildren(bool failAfterFirstChild, bool accessDenied)
+    {
+        var previousLibrary = BaseItem.LibraryManager;
+        var previousRepository = BaseItem.ItemRepository;
+        var previousLogger = BaseItem.Logger;
+        var library = new Mock<ILibraryManager>(MockBehavior.Strict);
+        var repository = new Mock<MediaBrowser.Controller.Persistence.IItemRepository>(MockBehavior.Strict);
+        var directory = new Mock<IDirectoryService>();
+        directory.Setup(d => d.IsAccessible(It.IsAny<string>())).Returns(true);
+        try
+        {
+            BaseItem.LibraryManager = library.Object;
+            BaseItem.ItemRepository = repository.Object;
+            BaseItem.Logger = Microsoft.Extensions.Logging.Abstractions.NullLogger<BaseItem>.Instance;
+            var folder = new FailingEnumerationFolder(failAfterFirstChild, accessDenied)
+            {
+                Id = Guid.NewGuid(),
+                Path = "/media/review-folder"
+            };
+            await folder.ValidateChildren(new Progress<double>(), new MetadataRefreshOptions(directory.Object), recursive: false, cancellationToken: TestContext.Current.CancellationToken).ConfigureAwait(true);
+            Assert.True(folder.EnumerationAttempted);
+            repository.VerifyNoOtherCalls();
+            library.VerifyNoOtherCalls();
+        }
+        finally
+        {
+            BaseItem.LibraryManager = previousLibrary;
+            BaseItem.ItemRepository = previousRepository;
+            BaseItem.Logger = previousLogger;
+        }
+    }
+
     [Fact]
     public void SetPrimaryVersionId_Null_RestoresTheItemsOwnPresentationKey()
     {
@@ -692,4 +729,25 @@ public class BaseItemTests
 
         Assert.Equal([primary.Id, alt1.Id, alt2.Id], ids);
     }
+
+    private sealed class FailingEnumerationFolder(bool failAfterFirstChild, bool accessDenied) : Folder
+    {
+        public bool EnumerationAttempted { get; private set; }
+
+        protected override IEnumerable<BaseItem> GetNonCachedChildren(IDirectoryService directoryService)
+        {
+            EnumerationAttempted = true;
+            if (failAfterFirstChild)
+            {
+                yield return new Movie { Id = Guid.NewGuid(), Path = "/media/review-folder/movie.mkv" };
+            }
+
+            if (accessDenied)
+            {
+                throw new System.Security.SecurityException("Simulated access failure");
+            }
+
+            throw new IOException("Simulated directory read failure");
+        }
+    }
 }