fix: Improve app data migration logic

Smarter migration logic that does a directory merge instead of a
straight move. This is designed to fail less in cases like the
`recyclarr` directory already existing.

CHANGELOG.md

@@ -28,6 +28,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Version information in help output has been fixed.
 - If a HOME directory is not available, throw an error to the user (use `--app-data` instead).
 - Create `$HOME/.config` (on Linux) if it does not exist.
+- Smarter migration logic in the `trash-updater` migration step that does a directory merge instead
+  of a straight move. This is designed to fail less in cases such as `recyclarr` directory already
+  existing.
 
 [appdata]: https://github.com/recyclarr/recyclarr/wiki/File-Structure
 

src/Recyclarr.Tests/Command/Initialization/Init/InitializeAppDataPathTest.cs

@@ -5,6 +5,7 @@ using FluentAssertions;
 using NSubstitute;
 using NUnit.Framework;
 using Recyclarr.Command;
+using Recyclarr.Command.Initialization;
 using Recyclarr.Command.Initialization.Init;
 using TestLibrary.AutoFixture;
 using TrashLib;
@@ -20,9 +21,11 @@ public class InitializeAppDataPathTest
         [Frozen] IEnvironment env,
         [Frozen] IAppPaths paths,
         [Frozen(Matching.ImplementedInterfaces)] MockFileSystem fs,
+        [Frozen(Matching.ImplementedInterfaces)] DefaultAppDataSetup appDataSetup,
         SonarrCommand cmd,
         InitializeAppDataPath sut)
     {
+        paths.DefaultAppDataDirectoryName.Returns("recyclarr");
         env.GetFolderPath(Arg.Any<Environment.SpecialFolder>(), Arg.Any<Environment.SpecialFolderOption>())
             .Returns("app_data");
 

src/Recyclarr.Tests/Migration/Steps/MigrateTrashUpdaterAppDataDirTest.cs

@@ -12,14 +12,15 @@ namespace Recyclarr.Tests.Migration.Steps;
 [Parallelizable(ParallelScope.All)]
 public class MigrateTrashUpdaterAppDataDirTest
 {
-    private static readonly string BasePath = Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData);
+    private const string BasePath = "base_path";
 
     [Test, AutoMockData]
     public void Migration_check_returns_true_if_trash_updater_dir_exists(
         [Frozen(Matching.ImplementedInterfaces)] MockFileSystem fs,
+        [Frozen(Matching.ImplementedInterfaces)] TestAppPaths paths,
         MigrateTrashUpdaterAppDataDir sut)
     {
-        fs.AddDirectory(Path.Combine(BasePath, "trash-updater"));
+        fs.AddDirectory(fs.Path.Combine(paths.BasePath, "trash-updater"));
         sut.CheckIfNeeded().Should().BeTrue();
     }
 
@@ -39,7 +40,7 @@ public class MigrateTrashUpdaterAppDataDirTest
         fs.AddDirectory(Path.Combine(BasePath, "trash-updater"));
         fs.AddDirectory(Path.Combine(BasePath, "recyclarr"));
 
-        var act = () => sut.Execute();
+        var act = sut.Execute;
 
         act.Should().Throw<IOException>();
     }
@@ -47,12 +48,15 @@ public class MigrateTrashUpdaterAppDataDirTest
     [Test, AutoMockData]
     public void Migration_success(
         [Frozen(Matching.ImplementedInterfaces)] MockFileSystem fs,
+        [Frozen(Matching.ImplementedInterfaces)] TestAppPaths paths,
         MigrateTrashUpdaterAppDataDir sut)
     {
-        fs.AddDirectory(Path.Combine(BasePath, "trash-updater"));
+        // Add file instead of directory since the migration step only operates on files
+        fs.AddFile(fs.Path.Combine(paths.BasePath, "trash-updater", "1", "2", "test.txt"), new MockFileData(""));
 
         sut.Execute();
 
-        fs.AllDirectories.Should().ContainSingle(x => Regex.IsMatch(x, @"[/\\]recyclarr$"));
+        fs.AllDirectories.Should().NotContain(x => x.Contains("trash-updater"));
+        fs.AllFiles.Should().Contain(x => Regex.IsMatch(x, @"[/\\]recyclarr[/\\]1[/\\]2[/\\]test.txt$"));
     }
 }

src/Recyclarr.Tests/Migration/Steps/TestAppPaths.cs

@@ -0,0 +1,15 @@
+using System.IO.Abstractions;
+
+namespace Recyclarr.Tests.Migration.Steps;
+
+public class TestAppPaths : AppPaths
+{
+    public string BasePath { get; }
+
+    public TestAppPaths(IFileSystem fs)
+        : base(fs)
+    {
+        BasePath = fs.Path.Combine("base", "path");
+        SetAppDataPath(fs.Path.Combine(BasePath, DefaultAppDataDirectoryName));
+    }
+}

src/Recyclarr/AppPaths.cs

@@ -15,6 +15,7 @@ public class AppPaths : IAppPaths
     }
 
     public string DefaultConfigFilename => "recyclarr.yml";
+    public string DefaultAppDataDirectoryName => "recyclarr";
 
     public bool IsAppDataPathValid => _appDataPath is not null;
     public void SetAppDataPath(string path) => _appDataPath = path;

src/Recyclarr/Command/Initialization/DefaultAppDataSetup.cs

@@ -0,0 +1,32 @@
+using System.IO.Abstractions;
+using Common;
+using TrashLib;
+
+namespace Recyclarr.Command.Initialization;
+
+public class DefaultAppDataSetup : IDefaultAppDataSetup
+{
+    private readonly IEnvironment _env;
+    private readonly IAppPaths _paths;
+    private readonly IFileSystem _fs;
+
+    public DefaultAppDataSetup(IEnvironment env, IAppPaths paths, IFileSystem fs)
+    {
+        _env = env;
+        _paths = paths;
+        _fs = fs;
+    }
+
+    public void SetupDefaultPath(bool forceCreate = false)
+    {
+        var appData = _env.GetFolderPath(Environment.SpecialFolder.ApplicationData,
+            forceCreate ? Environment.SpecialFolderOption.Create : Environment.SpecialFolderOption.None);
+
+        if (string.IsNullOrEmpty(appData))
+        {
+            throw new DirectoryNotFoundException("Unable to find the default app data directory");
+        }
+
+        _paths.SetAppDataPath(_fs.Path.Combine(appData, _paths.DefaultAppDataDirectoryName));
+    }
+}

src/Recyclarr/Command/Initialization/IDefaultAppDataSetup.cs

@@ -0,0 +1,6 @@
+namespace Recyclarr.Command.Initialization;
+
+public interface IDefaultAppDataSetup
+{
+    void SetupDefaultPath(bool forceCreate = false);
+}

src/Recyclarr/Command/Initialization/Init/InitializeAppDataPath.cs

@@ -10,12 +10,18 @@ public class InitializeAppDataPath : IServiceInitializer
     private readonly IFileSystem _fs;
     private readonly IAppPaths _paths;
     private readonly IEnvironment _env;
+    private readonly IDefaultAppDataSetup _appDataSetup;
 
-    public InitializeAppDataPath(IFileSystem fs, IAppPaths paths, IEnvironment env)
+    public InitializeAppDataPath(
+        IFileSystem fs,
+        IAppPaths paths,
+        IEnvironment env,
+        IDefaultAppDataSetup appDataSetup)
     {
         _fs = fs;
         _paths = paths;
         _env = env;
+        _appDataSetup = appDataSetup;
     }
 
     public void Initialize(ServiceCommand cmd)
@@ -36,11 +42,7 @@ public class InitializeAppDataPath : IServiceInitializer
 
             // Set app data path to application directory value (e.g. `$HOME/.config` on Linux) and ensure it is
             // created.
-            var appData = _env.GetFolderPath(
-                Environment.SpecialFolder.ApplicationData,
-                Environment.SpecialFolderOption.Create);
-
-            _paths.SetAppDataPath(_fs.Path.Combine(appData, "recyclarr"));
+            _appDataSetup.SetupDefaultPath(true);
         }
         else
         {

src/Recyclarr/Command/Initialization/InitializationAutofacModule.cs

@@ -11,12 +11,13 @@ public class InitializationAutofacModule : Module
     {
         base.Load(builder);
         builder.RegisterType<ServiceInitializationAndCleanup>().As<IServiceInitializationAndCleanup>();
+        builder.RegisterType<DefaultAppDataSetup>().As<IDefaultAppDataSetup>();
 
         // Initialization Services
         builder.RegisterTypes(
                 typeof(InitializeAppDataPath),
-                typeof(ServiceInitializer),
-                typeof(CheckMigrationNeeded))
+                typeof(CheckMigrationNeeded),
+                typeof(ServiceInitializer))
             .As<IServiceInitializer>()
             .OrderByRegistration();
 

src/Recyclarr/Command/MigrateCommand.cs

@@ -4,6 +4,7 @@ using CliFx.Attributes;
 using CliFx.Exceptions;
 using CliFx.Infrastructure;
 using JetBrains.Annotations;
+using Recyclarr.Command.Initialization;
 using Recyclarr.Migration;
 
 namespace Recyclarr.Command;
@@ -13,14 +14,17 @@ namespace Recyclarr.Command;
 public class MigrateCommand : ICommand
 {
     private readonly IMigrationExecutor _migration;
+    private readonly IDefaultAppDataSetup _appDataSetup;
 
-    public MigrateCommand(IMigrationExecutor migration)
+    public MigrateCommand(IMigrationExecutor migration, IDefaultAppDataSetup appDataSetup)
     {
         _migration = migration;
+        _appDataSetup = appDataSetup;
     }
 
     public ValueTask ExecuteAsync(IConsole console)
     {
+        _appDataSetup.SetupDefaultPath();
         PerformMigrations();
         return ValueTask.CompletedTask;
     }

src/Recyclarr/Migration/MigrationAutofacModule.cs

@@ -11,7 +11,11 @@ public class MigrationAutofacModule : Module
         builder.RegisterType<MigrationExecutor>().As<IMigrationExecutor>();
 
         // Migration Steps
-        builder.RegisterType<MigrateTrashYml>().As<IMigrationStep>();
-        builder.RegisterType<MigrateTrashUpdaterAppDataDir>().As<IMigrationStep>();
+        builder.RegisterTypes
+            (
+                typeof(MigrateTrashYml),
+                typeof(MigrateTrashUpdaterAppDataDir)
+            )
+            .As<IMigrationStep>();
     }
 }

src/Recyclarr/Migration/Steps/MigrateTrashUpdaterAppDataDir.cs

@@ -1,5 +1,7 @@
 using System.IO.Abstractions;
+using Common.Extensions;
 using JetBrains.Annotations;
+using TrashLib;
 
 namespace Recyclarr.Migration.Steps;
 
@@ -9,37 +11,35 @@ namespace Recyclarr.Migration.Steps;
 [UsedImplicitly]
 public class MigrateTrashUpdaterAppDataDir : IMigrationStep
 {
-    private readonly IFileSystem _fileSystem;
-
-    private readonly string _oldPath =
-        Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData), "trash-updater");
-
-    // Do not use AppPaths class here since that may change yet again in the future and break this migration step.
-    private readonly string _newPath =
-        Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData), "recyclarr");
+    private readonly IFileSystem _fs;
+    private readonly Lazy<string> _newPath, _oldPath;
 
     public int Order => 20;
-    public string Description { get; }
-    public IReadOnlyCollection<string> Remediation { get; }
     public bool Required => true;
 
-    public MigrateTrashUpdaterAppDataDir(IFileSystem fileSystem)
+    public string Description
+        => $"Merge files from old app data directory `{GetOldPath()}` into `{GetNewPath()}` and delete old directory";
+
+    public IReadOnlyCollection<string> Remediation => new[]
     {
-        _fileSystem = fileSystem;
-        Remediation = new[]
-        {
-            $"Check if `{_newPath}` already exists. If so, manually copy settings you want and then delete `{_oldPath}` to fix the error.",
-            $"Ensure Recyclarr has permission to recursively delete {_oldPath}",
-            $"Ensure Recyclarr has permission to create {_newPath}"
-        };
-
-        Description = $"Rename app data directory from `{_oldPath}` to `{_newPath}`";
-    }
+        $"Check if `{GetNewPath()}` already exists. If so, manually copy all files from `{GetOldPath()}` and delete it to fix the error.",
+        $"Ensure Recyclarr has permission to recursively delete {GetOldPath()}",
+        $"Ensure Recyclarr has permission to create and move files into {GetNewPath()}"
+    };
 
-    public bool CheckIfNeeded() => _fileSystem.Directory.Exists(_oldPath);
+    private string GetNewPath() => _newPath.Value;
+    private string GetOldPath() => _oldPath.Value;
 
-    public void Execute()
+    public MigrateTrashUpdaterAppDataDir(IFileSystem fs, IAppPaths paths)
     {
-        _fileSystem.Directory.Move(_oldPath, _newPath);
+        _fs = fs;
+
+        // Will be something like `/home/user/.config/recyclarr`.
+        _newPath = new Lazy<string>(paths.GetAppDataPath);
+        _oldPath = new Lazy<string>(() => _fs.Path.Combine(_fs.Path.GetDirectoryName(GetNewPath()), "trash-updater"));
     }
+
+    public bool CheckIfNeeded() => _fs.Directory.Exists(GetOldPath());
+
+    public void Execute() => _fs.MergeDirectory(GetOldPath(), GetNewPath());
 }

src/TrashLib/IAppPaths.cs

@@ -11,4 +11,5 @@ public interface IAppPaths
     string CacheDirectory { get; }
     string DefaultConfigFilename { get; }
     bool IsAppDataPathValid { get; }
+    string DefaultAppDataDirectoryName { get; }
 }