Improved CancellationToken usage, Added more logging to Workers, Added Code-comments (please future me, be thankful)

API/Schema/MangaContext/Chapter.cs

@@ -71,7 +71,11 @@ public class Chapter : Identifiable, IComparable<Chapter>
     /// Checks the filesystem if an archive at the ArchiveFilePath exists
     /// </summary>
     /// <returns>True if archive exists on disk</returns>
-    public bool CheckDownloaded() => File.Exists(FullArchiveFilePath);
+    public bool CheckDownloaded()
+    {
+        //TODO Log here
+        return File.Exists(FullArchiveFilePath);
+    } 
 
     /// Placeholders:
     /// %M Obj Name

API/Schema/MangaContext/MetadataFetchers/MetadataEntry.cs

@@ -32,4 +32,6 @@ public class MetadataEntry
         this.Identifier = identifier;
         this.MetadataFetcherName = metadataFetcherName;
     }
+    
+    public override string ToString() => $"{GetType().FullName} {MangaId} {MetadataFetcherName}";
 }

API/Schema/MangaContext/MetadataFetchers/MyAnimeList.cs

@@ -48,12 +48,22 @@ public class MyAnimeList : MetadataFetcher
     /// <exception cref="DbUpdateException"></exception>
     public override async Task UpdateMetadata(MetadataEntry metadataEntry, MangaContext dbContext, CancellationToken token)
     {
-        if (await dbContext.Mangas.FirstOrDefaultAsync(m => m.Key == metadataEntry.MangaId, token) is not { } dbManga)
+        Manga? dbManga = metadataEntry.Manga; //Might be null!
+        if (dbManga is null)
+        {
+            if (await dbContext.Mangas.FirstOrDefaultAsync(m => m.Key == metadataEntry.MangaId, token) is not
+                { } update)
                 throw new DbUpdateException("Manga not found");
+            dbManga = update;
+        }
 
+        // Load all collections (tags, links, authors)...
         foreach (CollectionEntry collectionEntry in dbContext.Entry(dbManga).Collections)
+        {
+            if(!collectionEntry.IsLoaded)
                 await collectionEntry.LoadAsync(token);
-        await dbContext.Entry(dbManga).Navigation(nameof(Manga.Library)).LoadAsync(token);
+        }
+        await dbContext.Entry(dbManga).Reference(m => m.Library).LoadAsync(token);
         
         MangaFull resultData;
         try

API/Tranga.cs

@@ -207,28 +207,4 @@ public static class Tranga
         
         return true;
     }
-
-    internal static bool AddChapterToContext((Chapter, MangaConnectorId<Chapter>) addChapter, MangaContext context, [NotNullWhen(true)] out Chapter? chapter, CancellationToken token) =>
-        AddChapterToContext(addChapter.Item1, addChapter.Item2, context, out chapter, token);
-
-    internal static bool AddChapterToContext(Chapter addChapter, MangaConnectorId<Chapter> addChId, MangaContext context, [NotNullWhen(true)] out Chapter? chapter, CancellationToken token)
-    {
-        chapter = context.Chapters.Where(ch => ch.Key == addChapter.Key)
-                .Include(ch => ch.ParentManga)
-                .Include(ch => ch.MangaConnectorIds)
-                .FirstOrDefault();
-        if (chapter is not null)
-        {
-            chapter.MangaConnectorIds = chapter.MangaConnectorIds.UnionBy(addChapter.MangaConnectorIds, id => id.Key).ToList();
-        }
-        else
-        {
-            context.Chapters.Add(addChapter);
-            chapter = addChapter;
-        }
-
-        if (context.Sync(token).Result is { success: false })
-            return false;
-        return true;
-    }
 }

API/Workers/BaseWorker.cs

@@ -26,7 +26,8 @@ public abstract class BaseWorker : Identifiable
     public IEnumerable<BaseWorker> MissingDependencies => DependsOn.Where(d => d.State < WorkerExecutionState.Completed);
     public bool AllDependenciesFulfilled => DependsOn.All(d => d.State >= WorkerExecutionState.Completed);
     internal WorkerExecutionState State { get; private set; }
-    protected CancellationTokenSource CancellationTokenSource = new ();
+    private CancellationTokenSource _cancellationTokenSource = new ();
+    protected CancellationToken CancellationToken => _cancellationTokenSource.Token;
     protected ILog Log { get; init; }
 
     /// <summary>
@@ -36,7 +37,7 @@ public abstract class BaseWorker : Identifiable
     {
         Log.Debug($"Cancelled {this}");
         this.State = WorkerExecutionState.Cancelled;
-        CancellationTokenSource.Cancel();
+        _cancellationTokenSource.Cancel();
     }
 
     /// <summary>
@@ -46,7 +47,7 @@ public abstract class BaseWorker : Identifiable
     {
         Log.Debug($"Failed {this}");
         this.State = WorkerExecutionState.Failed;
-        CancellationTokenSource.Cancel();
+        _cancellationTokenSource.Cancel();
     }
 
     public BaseWorker(IEnumerable<BaseWorker>? dependsOn = null)
@@ -75,7 +76,7 @@ public abstract class BaseWorker : Identifiable
     {
         // Start the worker
         Log.Debug($"Checking {this}");
-        this.CancellationTokenSource = new(TimeSpan.FromMinutes(10));
+        this._cancellationTokenSource = new(TimeSpan.FromMinutes(10));
         this.State = WorkerExecutionState.Waiting;
         
         // Wait for dependencies, start them if necessary
@@ -111,7 +112,7 @@ public abstract class BaseWorker : Identifiable
     private BaseWorker[] WaitForDependencies()
     {
         Log.Info($"Waiting for {MissingDependencies.Count()} Dependencies {this}:\n\t{string.Join("\n\t", MissingDependencies.Select(d => d.ToString()))}");
-        while (CancellationTokenSource.IsCancellationRequested == false && MissingDependencies.Any())
+        while (_cancellationTokenSource.IsCancellationRequested == false && MissingDependencies.Any())
         {
             Thread.Sleep(Tranga.Settings.WorkCycleTimeoutMs);  
         }

API/Workers/MangaDownloadWorkers/DownloadChapterFromMangaconnectorWorker.cs

@@ -13,28 +13,41 @@ using static System.IO.UnixFileMode;
 
 namespace API.Workers;
 
+/// <summary>
+/// Downloads single chapter for Manga from Mangaconnector
+/// </summary>
+/// <param name="chId"></param>
+/// <param name="dependsOn"></param>
 public class DownloadChapterFromMangaconnectorWorker(MangaConnectorId<Chapter> chId, IEnumerable<BaseWorker>? dependsOn = null)
     : BaseWorkerWithContext<MangaContext>(dependsOn)
 {
     internal readonly string MangaConnectorIdId = chId.Key;
     protected override async Task<BaseWorker[]> DoWorkInternal()
     {
-        if(await DbContext.MangaConnectorToChapter.FirstOrDefaultAsync(c => c.Key == MangaConnectorIdId, CancellationTokenSource.Token) is not { } mangaConnectorId)
+        Log.Debug($"Downloading chapter for MangaConnectorId {MangaConnectorIdId}...");
+        // Getting MangaConnector info
+        if (await DbContext.MangaConnectorToChapter
+                .Include(id => id.Obj)
+                .ThenInclude(c => c.ParentManga)
+                .ThenInclude(m => m.Library)
+                .FirstOrDefaultAsync(c => c.Key == MangaConnectorIdId, CancellationToken) is not { } mangaConnectorId)
+        {
+            Log.Error("Could not get MangaConnectorId.");
             return []; //TODO Exception?
+        }
         if (!Tranga.TryGetMangaConnector(mangaConnectorId.MangaConnectorName, out MangaConnector? mangaConnector))
+        {
+            Log.Error("Could not get MangaConnector.");
             return []; //TODO Exception?
+        }
+        Log.Debug($"Downloading chapter for MangaConnectorId {mangaConnectorId}...");
         
-        await DbContext.Entry(mangaConnectorId).Navigation(nameof(MangaConnectorId<Chapter>.Obj)).LoadAsync(CancellationTokenSource.Token);
         Chapter chapter = mangaConnectorId.Obj;
         if (chapter.Downloaded)
         {
             Log.Info("Chapter was already downloaded.");
             return [];
         }
-        
-        await DbContext.Entry(chapter).Navigation(nameof(Chapter.ParentManga)).LoadAsync(CancellationTokenSource.Token);
-        await DbContext.Entry(chapter.ParentManga).Navigation(nameof(Manga.Library)).LoadAsync(CancellationTokenSource.Token);
-
         if (chapter.ParentManga.LibraryId is null)
         {
             Log.Info($"Library is not set for {chapter.ParentManga} {chapter}");
@@ -97,9 +110,8 @@ public class DownloadChapterFromMangaconnectorWorker(MangaConnectorId<Chapter> c
         
         Log.Debug($"Creating ComicInfo.xml {chapter}");
         foreach (CollectionEntry collectionEntry in DbContext.Entry(chapter.ParentManga).Collections)
-            await collectionEntry.LoadAsync(CancellationTokenSource.Token);
+            await collectionEntry.LoadAsync(CancellationToken);
-        await DbContext.Entry(chapter.ParentManga).Navigation(nameof(Manga.Library)).LoadAsync(CancellationTokenSource.Token);
+        await File.WriteAllTextAsync(Path.Join(tempFolder, "ComicInfo.xml"), chapter.GetComicInfoXmlString(), CancellationToken);
-        await File.WriteAllTextAsync(Path.Join(tempFolder, "ComicInfo.xml"), chapter.GetComicInfoXmlString(), CancellationTokenSource.Token);
         
         Log.Debug($"Packaging images to archive {chapter}");
         //ZIP-it and ship-it
@@ -108,8 +120,11 @@ public class DownloadChapterFromMangaconnectorWorker(MangaConnectorId<Chapter> c
             File.SetUnixFileMode(saveArchiveFilePath, UserRead | UserWrite | UserExecute | GroupRead | GroupWrite | GroupExecute | OtherRead | OtherExecute);
         Directory.Delete(tempFolder, true); //Cleanup
 
-        chapter.Downloaded = true;
+        DbContext.Entry(chapter).Property(c => c.Downloaded).CurrentValue = true;
-        await DbContext.Sync(CancellationTokenSource.Token);
+        if(await DbContext.Sync(CancellationToken) is { success: false } e)
+            Log.Error($"Failed to save database changes: {e.exceptionMessage}");
+        
+        Log.Debug($"Downloaded chapter {chapter}.");
 
         return [];
     }
@@ -164,7 +179,7 @@ public class DownloadChapterFromMangaconnectorWorker(MangaConnectorId<Chapter> c
         }
         
         //TODO MangaConnector Selection
-        await DbContext.Entry(manga).Collection(m => m.MangaConnectorIds).LoadAsync(CancellationTokenSource.Token);
+        await DbContext.Entry(manga).Collection(m => m.MangaConnectorIds).LoadAsync(CancellationToken);
         MangaConnectorId<Manga> mangaConnectorId = manga.MangaConnectorIds.First();
         if (!Tranga.TryGetMangaConnector(mangaConnectorId.MangaConnectorName, out MangaConnector? mangaConnector))
         {
@@ -173,7 +188,7 @@ public class DownloadChapterFromMangaconnectorWorker(MangaConnectorId<Chapter> c
         }
 
         Log.Info($"Copying cover to {publicationFolder}");
-        await DbContext.Entry(mangaConnectorId).Navigation(nameof(MangaConnectorId<Manga>.Obj)).LoadAsync(CancellationTokenSource.Token);
+        await DbContext.Entry(mangaConnectorId).Navigation(nameof(MangaConnectorId<Manga>.Obj)).LoadAsync(CancellationToken);
         string? fileInCache = manga.CoverFileNameInCache ?? mangaConnector.SaveCoverImageToCache(mangaConnectorId);
         if (fileInCache is null)
         {

API/Workers/MangaDownloadWorkers/DownloadCoverFromMangaconnectorWorker.cs

@@ -4,23 +4,42 @@ using Microsoft.EntityFrameworkCore;
 
 namespace API.Workers;
 
+/// <summary>
+/// Downloads the cover for Manga from Mangaconnector
+/// </summary>
 public class DownloadCoverFromMangaconnectorWorker(MangaConnectorId<Manga> mcId, IEnumerable<BaseWorker>? dependsOn = null)
     : BaseWorkerWithContext<MangaContext>(dependsOn)
 {
     internal readonly string MangaConnectorIdId = mcId.Key;
     protected override async Task<BaseWorker[]> DoWorkInternal()
     {
-        if (await DbContext.MangaConnectorToManga.FirstOrDefaultAsync(c => c.Key == MangaConnectorIdId) is not { } mangaConnectorId)
+        Log.Debug($"Getting Cover for MangaConnectorId {MangaConnectorIdId}...");
+        // Getting MangaConnector info
+        if (await DbContext.MangaConnectorToManga
+                .Include(id => id.Obj)
+                .FirstOrDefaultAsync(c => c.Key == MangaConnectorIdId, CancellationToken) is not { } mangaConnectorId)
+        {
+            Log.Error("Could not get MangaConnectorId.");
             return []; //TODO Exception?
+        }
         if (!Tranga.TryGetMangaConnector(mangaConnectorId.MangaConnectorName, out MangaConnector? mangaConnector))
+        {
+            Log.Error("Could not get MangaConnector.");
             return []; //TODO Exception?
+        }
+        Log.Debug($"Getting Cover for MangaConnectorId {mangaConnectorId}...");
 
-        await DbContext.Entry(mangaConnectorId).Navigation(nameof(MangaConnectorId<Manga>.Obj)).LoadAsync(CancellationTokenSource.Token);
+        string? coverFileName = mangaConnector.SaveCoverImageToCache(mangaConnectorId);
-        Manga manga = mangaConnectorId.Obj;
+        if (coverFileName is null)
+        {
+            Log.Error($"Could not get Cover for MangaConnectorId {mangaConnectorId}.");
+            return [];
+        }
+        DbContext.Entry(mangaConnectorId.Obj).Property(m => m.CoverFileNameInCache).CurrentValue = coverFileName;
 
-        manga.CoverFileNameInCache = mangaConnector.SaveCoverImageToCache(mangaConnectorId);
+        if(await DbContext.Sync(CancellationToken) is { success: false } e)
+            Log.Error($"Failed to save database changes: {e.exceptionMessage}");
         
-        await DbContext.Sync(CancellationTokenSource.Token);
         return [];
     }
     

API/Workers/MangaDownloadWorkers/RetrieveMangaChaptersFromMangaconnectorWorker.cs

@@ -4,35 +4,51 @@ using Microsoft.EntityFrameworkCore;
 
 namespace API.Workers;
 
+/// <summary>
+/// Retrieves the metadata of available chapters on the Mangaconnector
+/// </summary>
+/// <param name="mcId"></param>
+/// <param name="language"></param>
+/// <param name="dependsOn"></param>
 public class RetrieveMangaChaptersFromMangaconnectorWorker(MangaConnectorId<Manga> mcId, string language, IEnumerable<BaseWorker>? dependsOn = null)
     : BaseWorkerWithContext<MangaContext>(dependsOn)
 {
     internal readonly string MangaConnectorIdId = mcId.Key;
     protected override async Task<BaseWorker[]> DoWorkInternal()
     {
-        if (await DbContext.MangaConnectorToManga.FirstOrDefaultAsync(c => c.Key == MangaConnectorIdId) is not { } mangaConnectorId)
+        Log.Debug($"Getting Chapters for MangaConnectorId {MangaConnectorIdId}...");
+        // Getting MangaConnector info
+        if (await DbContext.MangaConnectorToManga
+                .Include(id => id.Obj)
+                .FirstOrDefaultAsync(c => c.Key == MangaConnectorIdId, CancellationToken) is not { } mangaConnectorId)
+        {
+            Log.Error("Could not get MangaConnectorId.");
             return []; //TODO Exception?
+        }
         if (!Tranga.TryGetMangaConnector(mangaConnectorId.MangaConnectorName, out MangaConnector? mangaConnector))
+        {
+            Log.Error("Could not get MangaConnector.");
             return []; //TODO Exception?
+        }
+        Log.Debug($"Getting Chapters for MangaConnectorId {mangaConnectorId}...");
         
-        await DbContext.Entry(mangaConnectorId).Navigation(nameof(MangaConnectorId<Manga>.Obj)).LoadAsync(CancellationTokenSource.Token);
         Manga manga = mangaConnectorId.Obj;
-        await DbContext.Entry(manga).Collection(m => m.Chapters).LoadAsync(CancellationTokenSource.Token);
+        // Load existing Chapters (in database)
+        await DbContext.Entry(manga).Collection(m => m.Chapters).LoadAsync(CancellationToken);
         
         // This gets all chapters that are not downloaded
-        (Chapter, MangaConnectorId<Chapter>)[] allChapters =
+        (Chapter chapter, MangaConnectorId<Chapter> chapterId)[] allChapters =
             mangaConnector.GetChapters(mangaConnectorId, language).DistinctBy(c => c.Item1.Key).ToArray();
         
-        int addedChapters = 0;
+        int beforeAmount = manga.Chapters.Count;
-        foreach ((Chapter chapter, MangaConnectorId<Chapter> mcId) newChapter in allChapters)
+        Log.Debug($"Got {allChapters.Length} chapters from connector.");
-        {
+        DbContext.Entry(manga).Collection(m => m.Chapters).CurrentValue = manga.Chapters.UnionBy(allChapters.Select(c => c.chapter), c => c.Key);
-            if (Tranga.AddChapterToContext(newChapter, DbContext, out Chapter? addedChapter, CancellationTokenSource.Token) == false)
+        int afterAmount = manga.Chapters.Count;
-                continue;
-            manga.Chapters.Add(addedChapter);
-        }
-        Log.Info($"{manga.Chapters.Count} existing + {addedChapters} new chapters.");
         
-        await DbContext.Sync(CancellationTokenSource.Token);
+        Log.Debug($"Got {afterAmount} new chapters.");
+
+        if(await DbContext.Sync(CancellationToken) is { success: false } e)
+            Log.Error($"Failed to save database changes: {e.exceptionMessage}");
 
         return [];
     }

API/Workers/MoveMangaLibraryWorker.cs

@@ -3,6 +3,9 @@ using Microsoft.EntityFrameworkCore;
 
 namespace API.Workers;
 
+/// <summary>
+/// Moves a Manga to a different Library
+/// </summary>
 public class MoveMangaLibraryWorker(Manga manga, FileLibrary toLibrary, IEnumerable<BaseWorker>? dependsOn = null)
     : BaseWorkerWithContext<MangaContext>(dependsOn)
 {
@@ -10,20 +13,32 @@ public class MoveMangaLibraryWorker(Manga manga, FileLibrary toLibrary, IEnumera
     internal readonly string LibraryId = toLibrary.Key;
     protected override async Task<BaseWorker[]> DoWorkInternal()
     {
-        if (await DbContext.Mangas.FirstOrDefaultAsync(m => m.Key == MangaId, CancellationTokenSource.Token) is not { } manga)
+        Log.Debug("Moving Manga...");
+        // Get Manga (with Chapters and Library)
+        if (await DbContext.Mangas
+                .Include(m => m.Chapters)
+                .Include(m => m.Library)
+                .FirstOrDefaultAsync(m => m.Key == MangaId, CancellationToken) is not { } manga)
+        {
+            Log.Error("Could not find Manga.");
             return []; //TODO Exception?
-        if (await DbContext.FileLibraries.FirstOrDefaultAsync(l => l.Key == LibraryId, CancellationTokenSource.Token) is not { } toLibrary)
+        }
+        // Get new Library
+        if (await DbContext.FileLibraries.FirstOrDefaultAsync(l => l.Key == LibraryId, CancellationToken) is not { } toLibrary)
+        {
+            Log.Error("Could not find Library.");
             return []; //TODO Exception?
+        }
         
-        await DbContext.Entry(manga).Collection(m => m.Chapters).LoadAsync(CancellationTokenSource.Token);
+        // Save old Path (to later move chapters)
-        await DbContext.Entry(manga).Navigation(nameof(Manga.Library)).LoadAsync(CancellationTokenSource.Token);
-        
         Dictionary<Chapter, string> oldPath = manga.Chapters.ToDictionary(c => c, c => c.FullArchiveFilePath);
-        manga.Library = toLibrary;
+        // Set new Path
+        DbContext.Entry(manga).Property(m => m.Library).CurrentValue = toLibrary;
         
-        if (await DbContext.Sync(CancellationTokenSource.Token) is { success: false })
+        if (await DbContext.Sync(CancellationToken) is { success: false })
             return [];
 
+        // Create Jobs to move chapters from old to new Path
         return manga.Chapters.Select(c => new MoveFileOrFolderWorker(c.FullArchiveFilePath, oldPath[c])).ToArray<BaseWorker>();
     }
 

API/Workers/PeriodicWorkers/CheckForNewChaptersWorker.cs

@@ -3,23 +3,28 @@ using Microsoft.EntityFrameworkCore;
 
 namespace API.Workers;
 
+/// <summary>
+/// Creates Jobs to update available Chapters for all Manga that are marked for Download
+/// </summary>
 public class CheckForNewChaptersWorker(TimeSpan? interval = null, IEnumerable<BaseWorker>? dependsOn = null)
     : BaseWorkerWithContext<MangaContext>(dependsOn), IPeriodic
 {
     public DateTime LastExecution { get; set; } = DateTime.UnixEpoch;
     public TimeSpan Interval { get; set; } = interval??TimeSpan.FromMinutes(60);
     
-    protected override Task<BaseWorker[]> DoWorkInternal()
+    protected override async Task<BaseWorker[]> DoWorkInternal()
     {
-        IQueryable<MangaConnectorId<Manga>> connectorIdsManga = DbContext.MangaConnectorToManga
+        Log.Debug("Checking for new chapters...");
+        List<MangaConnectorId<Manga>> connectorIdsManga = await DbContext.MangaConnectorToManga
             .Include(id => id.Obj)
-            .Where(id => id.UseForDownload);
+            .Where(id => id.UseForDownload)
+            .ToListAsync(CancellationToken);
+        Log.Debug($"Creating {connectorIdsManga.Count} update jobs...");
 
-        List<BaseWorker> newWorkers = new();
+        List<BaseWorker> newWorkers = connectorIdsManga.Select(id => new RetrieveMangaChaptersFromMangaconnectorWorker(id, Tranga.Settings.DownloadLanguage))
-        foreach (MangaConnectorId<Manga> mangaConnectorId in connectorIdsManga)
+            .ToList<BaseWorker>();
-            newWorkers.Add(new RetrieveMangaChaptersFromMangaconnectorWorker(mangaConnectorId, Tranga.Settings.DownloadLanguage));
 
-        return new Task<BaseWorker[]>(() => newWorkers.ToArray());
+        return newWorkers.ToArray();
     }
 
 }

API/Workers/PeriodicWorkers/MaintenanceWorkers/RemoveOldNotificationsWorker.cs

@@ -1,7 +1,11 @@
 using API.Schema.NotificationsContext;
+using Microsoft.EntityFrameworkCore;
 
 namespace API.Workers.MaintenanceWorkers;
 
+/// <summary>
+/// Removes sent notifications from database
+/// </summary>
 public class RemoveOldNotificationsWorker(TimeSpan? interval = null, IEnumerable<BaseWorker>? dependsOn = null)
     : BaseWorkerWithContext<NotificationsContext>(dependsOn), IPeriodic
 {
@@ -10,10 +14,14 @@ public class RemoveOldNotificationsWorker(TimeSpan? interval = null, IEnumerable
     
     protected override async Task<BaseWorker[]> DoWorkInternal()
     {
-        IQueryable<Notification> toRemove = DbContext.Notifications.Where(n => n.IsSent || DateTime.UtcNow - n.Date > Interval);
+        Log.Debug("Removing old notifications...");
+        List<Notification> toRemove = await DbContext.Notifications.Where(n => n.IsSent).ToListAsync(CancellationToken);
+        Log.Debug($"Removing {toRemove.Count} old notifications...");
         DbContext.RemoveRange(toRemove);
         
-        await DbContext.Sync(CancellationTokenSource.Token);
+        if(await DbContext.Sync(CancellationToken) is { success: false } e)
+            Log.Error($"Failed to save database changes: {e.exceptionMessage}");
+        
         return [];
     }
 

API/Workers/PeriodicWorkers/SendNotificationsWorker.cs

@@ -1,8 +1,14 @@
 using API.Schema.NotificationsContext;
 using API.Schema.NotificationsContext.NotificationConnectors;
+using Microsoft.EntityFrameworkCore;
 
 namespace API.Workers;
 
+/// <summary>
+/// Send notifications to NotificationConnectors
+/// </summary>
+/// <param name="interval"></param>
+/// <param name="dependsOn"></param>
 public class SendNotificationsWorker(TimeSpan? interval = null, IEnumerable<BaseWorker>? dependsOn = null)
     : BaseWorkerWithContext<NotificationsContext>(dependsOn), IPeriodic
 {
@@ -10,19 +16,26 @@ public class SendNotificationsWorker(TimeSpan? interval = null, IEnumerable<Base
     public TimeSpan Interval { get; set; } = interval??TimeSpan.FromMinutes(1);
     protected override async Task<BaseWorker[]> DoWorkInternal()
     {
-        NotificationConnector[] connectors = DbContext.NotificationConnectors.ToArray();
+        Log.Debug("Sending notifications...");
-        Notification[] notifications = DbContext.Notifications.Where(n => n.IsSent == false).ToArray();
+        List<NotificationConnector> connectors = await DbContext.NotificationConnectors.ToListAsync(CancellationToken);
+        List<Notification> unsentNotifications = await DbContext.Notifications.Where(n => n.IsSent == false).ToListAsync(CancellationToken);
         
-        foreach (Notification notification in notifications)
+        Log.Debug($"Sending {unsentNotifications.Count} notifications to {connectors.Count} connectors...");
+        
+        unsentNotifications.ForEach(notification =>
         {
-            foreach (NotificationConnector connector in connectors)
+            connectors.ForEach(connector =>
             {
                 connector.SendNotification(notification.Title, notification.Message);
-                notification.IsSent = true;
+                DbContext.Entry(notification).Property(n => n.IsSent).CurrentValue = true;
-            }
+            });
-        }
+        });
+        
+        Log.Debug("Notifications sent.");
+        
+        if(await DbContext.Sync(CancellationToken) is { success: false } e)
+            Log.Error($"Failed to save database changes: {e.exceptionMessage}");
             
-        await DbContext.Sync(CancellationTokenSource.Token);
         return [];
     }
 

API/Workers/PeriodicWorkers/StartNewChapterDownloadsWorker.cs

@@ -3,22 +3,26 @@ using Microsoft.EntityFrameworkCore;
 
 namespace API.Workers;
 
+/// <summary>
+/// Create new Workers for Chapters on Manga marked for Download, that havent been downloaded yet.
+/// </summary>
 public class StartNewChapterDownloadsWorker(TimeSpan? interval = null, IEnumerable<BaseWorker>? dependsOn = null)
     : BaseWorkerWithContext<MangaContext>(dependsOn), IPeriodic
 {
 
     public DateTime LastExecution { get; set; } = DateTime.UnixEpoch;
     public TimeSpan Interval { get; set; } = interval ?? TimeSpan.FromMinutes(1);
-    protected override Task<BaseWorker[]> DoWorkInternal()
+    protected override async Task<BaseWorker[]> DoWorkInternal()
     {
-        IQueryable<MangaConnectorId<Chapter>> mangaConnectorIds = DbContext.MangaConnectorToChapter
+        // Get missing chapters
+        List<MangaConnectorId<Chapter>> missingChapters = await DbContext.MangaConnectorToChapter
             .Include(id => id.Obj)
-            .Where(id => id.Obj.Downloaded == false && id.UseForDownload);
+            .Where(id => id.Obj.Downloaded == false && id.UseForDownload)
+            .ToListAsync(CancellationToken);
         
-        List<BaseWorker> newWorkers = new();
+        // Create new jobs
-        foreach (MangaConnectorId<Chapter> mangaConnectorId in mangaConnectorIds)
+        List<BaseWorker> newWorkers = missingChapters.Select(mcId => new DownloadChapterFromMangaconnectorWorker(mcId)).ToList<BaseWorker>();
-            newWorkers.Add(new DownloadChapterFromMangaconnectorWorker(mangaConnectorId));
         
-        return new Task<BaseWorker[]>(() => newWorkers.ToArray());
+        return newWorkers.ToArray();
     }
 }

API/Workers/PeriodicWorkers/UpdateChaptersDownloadedWorker.cs

@@ -3,6 +3,9 @@ using Microsoft.EntityFrameworkCore;
 
 namespace API.Workers;
 
+/// <summary>
+/// Updates the database to reflect changes made on disk
+/// </summary>
 public class UpdateChaptersDownloadedWorker(TimeSpan? interval = null, IEnumerable<BaseWorker>? dependsOn = null)
     : BaseWorkerWithContext<MangaContext>(dependsOn), IPeriodic
 {
@@ -10,10 +13,14 @@ public class UpdateChaptersDownloadedWorker(TimeSpan? interval = null, IEnumerab
     public TimeSpan Interval { get; set; } = interval??TimeSpan.FromMinutes(60);
     protected override async Task<BaseWorker[]> DoWorkInternal()
     {
-        foreach (Chapter dbContextChapter in DbContext.Chapters.Include(c => c.ParentManga))
+        Log.Debug("Checking chapter files...");
-            dbContextChapter.Downloaded = dbContextChapter.CheckDownloaded();
+        List<Chapter> chapters = await DbContext.Chapters.Include(c => c.ParentManga).ToListAsync(CancellationToken);
+        Log.Debug($"Checking {chapters.Count} chapters...");
+        chapters.ForEach(chapter => DbContext.Entry(chapter).Property(c => c.Downloaded).CurrentValue = chapter.CheckDownloaded());
+
+        if(await DbContext.Sync(CancellationToken) is { success: false } e)
+            Log.Error($"Failed to save database changes: {e.exceptionMessage}");
         
-        await DbContext.Sync(CancellationTokenSource.Token);
         return [];
     }
 }

API/Workers/PeriodicWorkers/UpdateCoversWorker.cs

@@ -1,7 +1,13 @@
 using API.Schema.MangaContext;
+using Microsoft.EntityFrameworkCore;
 
 namespace API.Workers;
 
+/// <summary>
+/// Creates Workers to update covers for Manga
+/// </summary>
+/// <param name="interval"></param>
+/// <param name="dependsOn"></param>
 public class UpdateCoversWorker(TimeSpan? interval = null, IEnumerable<BaseWorker>? dependsOn = null)
     : BaseWorkerWithContext<MangaContext>(dependsOn), IPeriodic
 {
@@ -9,11 +15,10 @@ public class UpdateCoversWorker(TimeSpan? interval = null, IEnumerable<BaseWorke
     public DateTime LastExecution { get; set; } = DateTime.UnixEpoch;
     public TimeSpan Interval { get; set; } = interval ?? TimeSpan.FromHours(6);
     
-    protected override Task<BaseWorker[]> DoWorkInternal()
+    protected override async Task<BaseWorker[]> DoWorkInternal()
     {
-        List<BaseWorker> workers = new();
+        List<MangaConnectorId<Manga>> manga = await DbContext.MangaConnectorToManga.Where(mcId => mcId.UseForDownload).ToListAsync(CancellationToken);
-        foreach (MangaConnectorId<Manga> mangaConnectorId in DbContext.MangaConnectorToManga)
+        List<BaseWorker> newWorkers = manga.Select(m => new DownloadCoverFromMangaconnectorWorker(m)).ToList<BaseWorker>();
-            workers.Add(new DownloadCoverFromMangaconnectorWorker(mangaConnectorId));
+        return newWorkers.ToArray();
-        return new Task<BaseWorker[]>(() => workers.ToArray());
     }
 }

API/Workers/PeriodicWorkers/UpdateMetadataWorker.cs

@@ -4,6 +4,11 @@ using Microsoft.EntityFrameworkCore;
 
 namespace API.Workers;
 
+/// <summary>
+/// Updates Metadata for all Manga
+/// </summary>
+/// <param name="interval"></param>
+/// <param name="dependsOn"></param>
 public class UpdateMetadataWorker(TimeSpan? interval = null, IEnumerable<BaseWorker>? dependsOn = null)
     : BaseWorkerWithContext<MangaContext>(dependsOn), IPeriodic
 {
@@ -13,18 +18,27 @@ public class UpdateMetadataWorker(TimeSpan? interval = null, IEnumerable<BaseWor
     
     protected override async Task<BaseWorker[]> DoWorkInternal()
     {
-        IQueryable<string> mangaIds = DbContext.MangaConnectorToManga
+        Log.Debug("Updating metadata...");
-            .Where(m => m.UseForDownload)
+        // Get MetadataEntries of Manga marked for download
-            .Select(m => m.ObjId);
+        List<MetadataEntry> metadataEntriesToUpdate = await DbContext.MangaConnectorToManga
-        IQueryable<MetadataEntry> metadataEntriesToUpdate = DbContext.MetadataEntries
+            .Where(m => m.UseForDownload) // Get marked Manga
-            .Include(e => e.MetadataFetcher)
+            .Join(
-            .Where(e =>
+                DbContext.MetadataEntries.Include(e => e.MetadataFetcher).Include(e => e.Manga),
-                mangaIds.Any(id => id == e.MangaId));
+                mcId => mcId.ObjId,
+                e => e.MangaId,
+                (mcId, e) => e) // return MetadataEntry
+            .ToListAsync(CancellationToken);
+        Log.Debug($"Updating metadata of {metadataEntriesToUpdate.Count} manga...");
 
         foreach (MetadataEntry metadataEntry in metadataEntriesToUpdate)
-            await metadataEntry.MetadataFetcher.UpdateMetadata(metadataEntry, DbContext, CancellationTokenSource.Token);
+        {
+            Log.Debug($"Updating metadata of {metadataEntry}...");
+            await metadataEntry.MetadataFetcher.UpdateMetadata(metadataEntry, DbContext, CancellationToken);
+        }
+        Log.Debug("Updated metadata.");
 
-        await DbContext.Sync(CancellationTokenSource.Token);
+        if(await DbContext.Sync(CancellationToken) is { success: false } e)
+            Log.Error($"Failed to save database changes: {e.exceptionMessage}");
 
         return [];
     }