Clean up domain entities: shared picture value object, lifecycle and ownership interfaces, explicit tables

backend/Core/Musify.Application/Albums/CreateAlbum.cs

@@ -56,7 +56,7 @@ public class CreateAlbumCommandHandler(
             NormalizedTitle = title.ToUpperInvariant(),
             Description = request.Description,
             ReleaseYear = request.ReleaseYear,
-            Pictures = AlbumPictures.Pending(intent.ObjectName)
+            Pictures = EntityPictures.Pending(intent.ObjectName)
         };
 
         await database.Albums.AddAsync(album, cancellationToken);

backend/Core/Musify.Application/Albums/UpdateAlbum.cs

@@ -64,7 +64,7 @@ public class UpdateAlbumCommandHandler(
                 return validation.Errors;
 
             var pictureIntent = validation.Value;
-            album.Pictures = AlbumPictures.Pending(pictureIntent.ObjectName);
+            album.Pictures = EntityPictures.Pending(pictureIntent.ObjectName);
             var finalPictureKey = albumConfiguration.Routes.BuildOriginalPicturePath(request.UserId, pictureIntent.ObjectName);
 
             var publishResult = await PublishUpdateAlbumPictureSourceEventAsync(

backend/Core/Musify.Application/PlayLists/AddTrackToPlayList.cs

@@ -24,7 +24,7 @@ public class AddTrackToPlayListCommandHandler(
         if (playList == null)
             return AppErrors.NotFound("PlayList", request.PlayListId);
 
-        if (playList.UserId != request.UserId)
+        if (playList.OwnerUserId != request.UserId)
             return AppErrors.Forbidden("PlayList", request.PlayListId);
 
         var trackExists = await database.Tracks

backend/Core/Musify.Application/PlayLists/CreatePlayList.cs

@@ -17,7 +17,7 @@ public record CreatePlayListCommand(
     string Name,
     string? Description,
     Guid? PictureIntentId,
-    PlaylistVisibility Visibility = PlaylistVisibility.Private)
+    PlayListVisibility Visibility = PlayListVisibility.Private)
     : ICommand<ErrorOr<PlayListApplicationResponse>>;
 
 public class CreatePlayListCommandHandler(
@@ -30,7 +30,7 @@ public class CreatePlayListCommandHandler(
     UploadIntentConfiguration uploadIntentConfiguration)
     : ICommandHandler<CreatePlayListCommand, ErrorOr<PlayListApplicationResponse>>
 {
-    private sealed record ResolvedPlayListPictures(PlayListPictures? Pictures, UploadIntent? Intent);
+    private sealed record ResolvedPlayListPictures(EntityPictures? Pictures, UploadIntent? Intent);
 
     public async ValueTask<ErrorOr<PlayListApplicationResponse>> Handle(CreatePlayListCommand request, CancellationToken cancellationToken)
     {
@@ -51,7 +51,7 @@ public class CreatePlayListCommandHandler(
 
         var playList = new PlayList
         {
-            UserId = request.UserId,
+            OwnerUserId = request.UserId,
             Name = request.Name.Trim(),
             NormalizedName = request.Name.Trim().ToUpperInvariant(),
             Description = string.IsNullOrWhiteSpace(request.Description) ? null : request.Description.Trim(),
@@ -96,7 +96,7 @@ public class CreatePlayListCommandHandler(
         if (validation.IsError)
             return validation.Errors;
 
-        return new ResolvedPlayListPictures(PlayListPictures.Pending(validation.Value.ObjectName), validation.Value);
+        return new ResolvedPlayListPictures(EntityPictures.Pending(validation.Value.ObjectName), validation.Value);
     }
 
     private async Task<ErrorOr<Success>> PublishCreatePlayListEventAsync(

backend/Core/Musify.Application/PlayLists/DeletePlayList.cs

@@ -27,7 +27,7 @@ public class DeletePlayListCommandHandler(
             return Error.NotFound();
         }
 
-        if (playList.UserId != request.UserId)
+        if (playList.OwnerUserId != request.UserId)
         {
             logger.LogWarning("Playlist {PlayListId} does not belong to user {UserId}", request.PlayListId, request.UserId);
             return AppErrors.Forbidden("PlayList", request.PlayListId);

backend/Core/Musify.Application/PlayLists/GetPlayListById.cs

@@ -32,8 +32,8 @@ public class GetPlayListByIdQueryHandler(IDatabase database)
         if (entry == null)
             return Error.NotFound();
 
-        if (entry.PlayList.Visibility == PlaylistVisibility.Private
+        if (entry.PlayList.Visibility == PlayListVisibility.Private
-            && entry.PlayList.UserId != request.RequestingUserId)
+            && entry.PlayList.OwnerUserId != request.RequestingUserId)
         {
             return Error.NotFound();
         }

backend/Core/Musify.Application/PlayLists/GetPlayListCover.cs

@@ -24,7 +24,7 @@ public class GetPlayListCoverQueryHandler(
     {
         var owned = await database.PlayLists.AsNoTracking()
             .Where(e => e.Id == request.PlayListId && e.LifeCycleStatus == LifeCycleStatus.Active)
-            .Select(e => new { OwnerUserId = e.UserId, e.Pictures })
+            .Select(e => new { OwnerUserId = e.OwnerUserId, e.Pictures })
             .SingleOrDefaultAsync(cancellationToken);
 
         if (owned?.Pictures == null)

backend/Core/Musify.Application/PlayLists/GetPlayListTracks.cs

@@ -27,7 +27,7 @@ public class GetPlayListTracksQueryHandler(IDatabase database)
             .AnyAsync(
                 p => p.Id == request.PlayListId
                     && p.LifeCycleStatus == LifeCycleStatus.Active
-                    && (p.Visibility == PlaylistVisibility.Public || p.UserId == request.ViewerId),
+                    && (p.Visibility == PlayListVisibility.Public || p.OwnerUserId == request.ViewerId),
                 cancellationToken);
         if (!playListExists)
             return Error.NotFound();

backend/Core/Musify.Application/PlayLists/GetPlayListsByUserId.cs

@@ -25,9 +25,9 @@ public class GetPlayListsByUserIdQueryHandler(IDatabase database)
     {
         var playListsQuery = database.PlayLists
             .AsNoTracking()
-            .Where(p => p.UserId == request.UserId
+            .Where(p => p.OwnerUserId == request.UserId
                 && p.LifeCycleStatus == LifeCycleStatus.Active
-                && (p.Visibility == PlaylistVisibility.Public || p.UserId == request.ViewerId));
+                && (p.Visibility == PlayListVisibility.Public || p.OwnerUserId == request.ViewerId));
 
         if (!string.IsNullOrEmpty(request.Name))
         {

backend/Core/Musify.Application/PlayLists/RemoveTrackFromPlayList.cs

@@ -23,7 +23,7 @@ public class RemoveTrackFromPlayListCommandHandler(
         if (playList == null)
             return AppErrors.NotFound("PlayList", request.PlayListId);
 
-        if (playList.UserId != request.UserId)
+        if (playList.OwnerUserId != request.UserId)
             return AppErrors.Forbidden("PlayList", request.PlayListId);
 
         var playListTracks = await database.PlayListHasTracks

backend/Core/Musify.Application/PlayLists/Responses/PlayListApplicationResponse.cs

@@ -10,7 +10,7 @@ public record PlayListApplicationResponse(
     string? SmallImageKeyName,
     string? MediumImageKeyName,
     string? LargeImageKeyName,
-    PlaylistVisibility Visibility,
+    PlayListVisibility Visibility,
     DateTime CreatedAt,
     DateTime UpdatedAt,
     IReadOnlyList<Guid> CoverTrackIds)

backend/Core/Musify.Application/PlayLists/UpdatePlayList.cs

@@ -19,7 +19,7 @@ public record UpdatePlayListCommand(
     string? NewName,
     string? NewDescription,
     Guid? NewPictureIntentId,
-    PlaylistVisibility? NewVisibility = null)
+    PlayListVisibility? NewVisibility = null)
     : ICommand<ErrorOr<PlayListApplicationResponse>>;
 
 public class UpdatePlayListCommandHandler(
@@ -41,7 +41,7 @@ public class UpdatePlayListCommandHandler(
             return Error.NotFound();
         }
 
-        if (playListEntity.UserId != request.UserId)
+        if (playListEntity.OwnerUserId != request.UserId)
         {
             logger.LogWarning("User {UserId} is not the owner of playlist {PlayListId}", request.UserId, request.PlayListId);
             return AppErrors.Forbidden("PlayList", request.PlayListId);
@@ -72,7 +72,7 @@ public class UpdatePlayListCommandHandler(
                 return validation.Errors;
 
             var pictureIntent = validation.Value;
-            playListEntity.Pictures = PlayListPictures.Pending(pictureIntent.ObjectName);
+            playListEntity.Pictures = EntityPictures.Pending(pictureIntent.ObjectName);
             var finalPictureKey = playListConfiguration.Routes.BuildOriginalPicturePath(request.UserId, pictureIntent.ObjectName);
 
             var publishResult = await PublishUpdatePlayListPictureSourceEventAsync(

backend/Core/Musify.Application/Services/UploadIntentValidator.cs

@@ -52,7 +52,7 @@ public sealed class UploadIntentValidator(
         if (intent.IsConsumed)
             return Error.Conflict(description: "Upload intent has already been consumed.");
 
-        if (intent.IsExpired)
+        if (intent.IsExpiredAt(DateTime.UtcNow))
             return Error.Validation(description: "Upload intent has expired.");
 
         var metadata = await storageService.HeadObjectAsync(intent.Bucket, intent.Key, cancellationToken);

backend/Core/Musify.Domain/Abstractions/IHasLifeCycle.cs

@@ -0,0 +1,10 @@
+using Musify.Domain.ValueObjects;
+
+namespace Musify.Domain.Abstractions;
+
+public interface IHasLifeCycle
+{
+    public Guid Id { get; }
+
+    public LifeCycleStatus LifeCycleStatus { get; set; }
+}

backend/Core/Musify.Domain/Abstractions/IOwnedEntity.cs

@@ -0,0 +1,8 @@
+namespace Musify.Domain.Abstractions;
+
+public interface IOwnedEntity
+{
+    public Guid Id { get; }
+
+    public long OwnerUserId { get; }
+}

backend/Core/Musify.Domain/Entities/Album.cs

@@ -5,17 +5,15 @@ using Musify.Domain.ValueObjects;
 
 namespace Musify.Domain.Entities;
 
-#pragma warning disable CS8618
+[Table("Albums")]
-public class Album : IAuditable
+public class Album : IAuditable, IHasLifeCycle, IOwnedEntity
 {
     [Key]
     public Guid Id { get; set; } = Guid.NewGuid();
 
-    [Required]
     [MaxLength(200)]
     public required string Title { get; set; }
 
-    [Required]
     [MaxLength(200)]
     public required string NormalizedTitle { get; set; }
 
@@ -24,21 +22,17 @@ public class Album : IAuditable
 
     public int? ReleaseYear { get; set; }
 
-    public AlbumPictures? Pictures { get; set; }
+    public EntityPictures? Pictures { get; set; }
 
-    [Required]
     public required long OwnerUserId { get; set; }
 
     [ForeignKey(nameof(OwnerUserId))]
-    public User Owner { get; set; }
+    public User Owner { get; set; } = null!;
 
-    [Required]
     public LifeCycleStatus LifeCycleStatus { get; set; } = LifeCycleStatus.Active;
 
-    [Required]
     public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
 
-    [Required]
     public DateTime UpdatedAt { get; set; } = DateTime.UtcNow;
 
     public ICollection<AlbumHasTrack> AlbumTracks { get; set; } = new List<AlbumHasTrack>();

backend/Core/Musify.Domain/Entities/AlbumHasTrack.cs

@@ -1,29 +1,23 @@
-using System.ComponentModel.DataAnnotations;
 using System.ComponentModel.DataAnnotations.Schema;
 
 namespace Musify.Domain.Entities;
 
-#pragma warning disable CS8618
 [Table("AlbumHasTrack")]
 public class AlbumHasTrack
 {
     public Guid Id { get; set; } = Guid.NewGuid();
 
-    [Required]
     public required Guid AlbumId { get; set; }
 
-    [Required]
     public required Guid TrackId { get; set; }
 
-    [Required]
     public int TrackNumber { get; set; } = 1;
 
-    [Required]
     public DateTime AddedAt { get; set; } = DateTime.UtcNow;
 
     [ForeignKey(nameof(AlbumId))]
-    public Album Album { get; set; }
+    public Album Album { get; set; } = null!;
 
     [ForeignKey(nameof(TrackId))]
-    public Track Track { get; set; }
+    public Track Track { get; set; } = null!;
 }

backend/Core/Musify.Domain/Entities/ListeningHistory.cs

@@ -3,20 +3,16 @@ using System.ComponentModel.DataAnnotations.Schema;
 
 namespace Musify.Domain.Entities;
 
-#pragma warning disable CS8618
 [Table("ListeningHistory")]
 public class ListeningHistory
 {
     [Key]
     public Guid Id { get; set; } = Guid.NewGuid();
 
-    [Required]
     public required long UserId { get; set; }
 
-    [Required]
     public required Guid TrackId { get; set; }
 
-    [Required]
     public DateTime ListenedAt { get; set; } = DateTime.UtcNow;
 
     public double? PlayedSeconds { get; set; }
@@ -26,8 +22,8 @@ public class ListeningHistory
     public bool IsCounted { get; set; }
 
     [ForeignKey(nameof(UserId))]
-    public User User { get; set; }
+    public User User { get; set; } = null!;
 
     [ForeignKey(nameof(TrackId))]
-    public Track Track { get; set; }
+    public Track Track { get; set; } = null!;
 }

backend/Core/Musify.Domain/Entities/Mix.cs

@@ -5,34 +5,28 @@ using Musify.Domain.Abstractions;
 
 namespace Musify.Domain.Entities;
 
-#pragma warning disable CS8618
 [Table("Mixes")]
 public class Mix : IAuditable
 {
     [Key]
     public Guid Id { get; set; } = Guid.NewGuid();
 
-    [Required]
     public required long UserId { get; set; }
 
-    [Required]
     [MaxLength(100)]
     public required string Title { get; set; }
 
     [MaxLength(256)]
     public string? Subtitle { get; set; }
 
-    [Required]
+    public int Position { get; set; }
-    public int Position { get; set; } = 0;
 
-    [Required]
     public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
 
-    [Required]
     public DateTime UpdatedAt { get; set; } = DateTime.UtcNow;
 
     [ForeignKey(nameof(UserId))]
-    public User User { get; set; }
+    public User User { get; set; } = null!;
 
     public ICollection<MixItem> Items { get; set; } = new List<MixItem>();
 }

backend/Core/Musify.Domain/Entities/MixItem.cs

@@ -3,25 +3,21 @@ using System.ComponentModel.DataAnnotations.Schema;
 
 namespace Musify.Domain.Entities;
 
-#pragma warning disable CS8618
 [Table("MixItems")]
 public class MixItem
 {
     [Key]
     public Guid Id { get; set; } = Guid.NewGuid();
 
-    [Required]
     public required Guid MixId { get; set; }
 
-    [Required]
+    public int Position { get; set; }
-    public int Position { get; set; } = 0;
 
-    [Required]
     public required Guid TrackId { get; set; }
 
     [ForeignKey(nameof(MixId))]
-    public Mix Mix { get; set; }
+    public Mix Mix { get; set; } = null!;
 
     [ForeignKey(nameof(TrackId))]
-    public Track Track { get; set; }
+    public Track Track { get; set; } = null!;
 }

backend/Core/Musify.Domain/Entities/PlayList.cs

@@ -6,43 +6,36 @@ using Musify.Domain.ValueObjects;
 
 namespace Musify.Domain.Entities;
 
-#pragma warning disable CS8618
 [Table("PlayLists")]
-public class PlayList : IAuditable
+public class PlayList : IAuditable, IHasLifeCycle, IOwnedEntity
 {
     [Key]
     public Guid Id { get; set; } = Guid.NewGuid();
 
-    [Required]
+    [Column("UserId")]
-    public required long UserId { get; set; }
+    public required long OwnerUserId { get; set; }
 
-    [Required]
     [MaxLength(50)]
     public required string Name { get; set; }
 
-    [Required]
     [MaxLength(50)]
     public required string NormalizedName { get; set; }
 
     [MaxLength(256)]
     public string? Description { get; set; }
 
-    public PlayListPictures? Pictures { get; set; }
+    public EntityPictures? Pictures { get; set; }
 
-    [Required]
     public LifeCycleStatus LifeCycleStatus { get; set; } = LifeCycleStatus.Active;
 
-    [Required]
+    public PlayListVisibility Visibility { get; set; } = PlayListVisibility.Private;
-    public PlaylistVisibility Visibility { get; set; } = PlaylistVisibility.Private;
 
-    [Required]
     public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
 
-    [Required]
     public DateTime UpdatedAt { get; set; } = DateTime.UtcNow;
 
-    [ForeignKey(nameof(UserId))]
+    [ForeignKey(nameof(OwnerUserId))]
-    public User User { get; set; }
+    public User Owner { get; set; } = null!;
 
     public ICollection<PlayListHasTrack> PlayListTracks { get; set; } = new List<PlayListHasTrack>();
 }

backend/Core/Musify.Domain/Entities/PlayListHasTrack.cs

@@ -1,29 +1,23 @@
-using System.ComponentModel.DataAnnotations;
 using System.ComponentModel.DataAnnotations.Schema;
 
 namespace Musify.Domain.Entities;
 
-#pragma warning disable CS8618
 [Table("PlayListHasTrack")]
 public class PlayListHasTrack
 {
     public Guid Id { get; set; } = Guid.NewGuid();
 
-    [Required]
     public required Guid PlayListId { get; set; }
 
-    [Required]
     public required Guid TrackId { get; set; }
 
-    [Required]
+    public int Position { get; set; }
-    public int Position { get; set; } = 0;
 
-    [Required]
     public DateTime AddedAt { get; set; } = DateTime.UtcNow;
 
     [ForeignKey(nameof(PlayListId))]
-    public PlayList PlayList { get; set; }
+    public PlayList PlayList { get; set; } = null!;
 
     [ForeignKey(nameof(TrackId))]
-    public Track Track { get; set; }
+    public Track Track { get; set; } = null!;
 }

backend/Core/Musify.Domain/Entities/Track.cs

@@ -5,39 +5,31 @@ using Musify.Domain.ValueObjects;
 
 namespace Musify.Domain.Entities;
 
-#pragma warning disable CS8618
+[Table("Tracks")]
-public class Track : IAuditable
+public class Track : IAuditable, IHasLifeCycle, IOwnedEntity
 {
     [Key]
     public Guid Id { get; set; } = Guid.NewGuid();
 
-    [Required]
     [MaxLength(200)]
     public required string Title { get; set; }
 
-    [Required]
     [MaxLength(200)]
     public required string NormalizedTitle { get; set; }
 
-    [Required]
     public double DurationSeconds { get; set; }
 
-    [Required]
     public required long OwnerUserId { get; set; }
 
     [ForeignKey(nameof(OwnerUserId))]
-    public required User Owner { get; set; }
+    public User Owner { get; set; } = null!;
 
-    [Required]
     public LifeCycleStatus LifeCycleStatus { get; set; } = LifeCycleStatus.Active;
 
-    [Required]
     public bool IsExplicit { get; set; }
 
-    [Required]
     public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
 
-    [Required]
     public DateTime UpdatedAt { get; set; } = DateTime.UtcNow;
 
     public TrackPictures Pictures { get; set; } = new();

backend/Core/Musify.Domain/Entities/TrackLike.cs

@@ -3,25 +3,21 @@ using System.ComponentModel.DataAnnotations.Schema;
 
 namespace Musify.Domain.Entities;
 
-#pragma warning disable CS8618
 [Table("TrackLikes")]
 public class TrackLike
 {
     [Key]
     public Guid Id { get; set; } = Guid.NewGuid();
 
-    [Required]
     public required long UserId { get; set; }
 
-    [Required]
     public required Guid TrackId { get; set; }
 
-    [Required]
     public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
 
     [ForeignKey(nameof(UserId))]
-    public User User { get; set; }
+    public User User { get; set; } = null!;
 
     [ForeignKey(nameof(TrackId))]
-    public Track Track { get; set; }
+    public Track Track { get; set; } = null!;
 }

backend/Core/Musify.Domain/Entities/TrackTag.cs

@@ -4,18 +4,16 @@ using Musify.Domain.ValueObjects;
 
 namespace Musify.Domain.Entities;
 
-#pragma warning disable CS8618
+[Table("TrackTags")]
 public class TrackTag
 {
     [Key]
     public Guid Id { get; set; } = Guid.NewGuid();
 
-    [Required]
     public required Guid TrackId { get; set; }
 
-    [Required]
     public required Genre Tag { get; set; }
 
     [ForeignKey(nameof(TrackId))]
-    public Track Track { get; set; }
+    public Track Track { get; set; } = null!;
 }

backend/Core/Musify.Domain/Entities/UploadIntent.cs

@@ -11,40 +11,34 @@ public class UploadIntent
     [Key]
     public Guid Id { get; set; } = Guid.NewGuid();
 
-    [Required]
     public required long UserId { get; set; }
 
-    [Required, MaxLength(128)]
+    [MaxLength(128)]
     public required string Bucket { get; set; }
 
-    [Required, MaxLength(512)]
+    [MaxLength(512)]
     public required string Key { get; set; }
 
-    [Required, MaxLength(128)]
+    [MaxLength(128)]
     public required string ObjectName { get; set; }
 
-    [Required, MaxLength(128)]
+    [MaxLength(128)]
     public required string ContentType { get; set; }
 
     public long? ExpectedSizeBytes { get; set; }
 
-    [Required]
     public UploadIntentPurpose Purpose { get; set; }
 
-    [Required]
     public UploadIntentStatus Status { get; set; } = UploadIntentStatus.Issued;
 
-    [Required]
     public DateTime ExpiresAt { get; set; }
 
-    [Required]
     public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
 
     [NotMapped]
     public bool IsConsumed => Status == UploadIntentStatus.Consumed;
 
-    [NotMapped]
+    public bool IsExpiredAt(DateTime now) => Status == UploadIntentStatus.Expired || ExpiresAt < now;
-    public bool IsExpired => Status == UploadIntentStatus.Expired || ExpiresAt < DateTime.UtcNow;
 
     [ForeignKey(nameof(UserId))]
     public User User { get; set; } = null!;

backend/Core/Musify.Domain/Entities/User.cs

@@ -11,11 +11,9 @@ public class User : IAuditable
     [DatabaseGenerated(DatabaseGeneratedOption.None)]
     public required long Id { get; set; }
 
-    [Required]
     [MaxLength(48)]
     public required string Name { get; set; }
 
-    [Required]
     [MaxLength(48)]
     public required string NormalizedName { get; set; }
 
@@ -28,10 +26,8 @@ public class User : IAuditable
     [MaxLength(2048)]
     public string? ProfilePictureUrl { get; set; }
 
-    [Required]
     public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
 
-    [Required]
     public DateTime UpdatedAt { get; set; } = DateTime.UtcNow;
 
     public ICollection<UserHasTrack> UserTracks { get; set; } = new List<UserHasTrack>();

backend/Core/Musify.Domain/Entities/UserFollow.cs

@@ -3,25 +3,21 @@ using System.ComponentModel.DataAnnotations.Schema;
 
 namespace Musify.Domain.Entities;
 
-#pragma warning disable CS8618
 [Table("UserFollows")]
 public class UserFollow
 {
     [Key]
     public Guid Id { get; set; } = Guid.NewGuid();
 
-    [Required]
     public required long FollowerId { get; set; }
 
-    [Required]
     public required long FollowedId { get; set; }
 
-    [Required]
     public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
 
     [ForeignKey(nameof(FollowerId))]
-    public User Follower { get; set; }
+    public User Follower { get; set; } = null!;
 
     [ForeignKey(nameof(FollowedId))]
-    public User Followed { get; set; }
+    public User Followed { get; set; } = null!;
 }

backend/Core/Musify.Domain/Entities/UserHasTrack.cs

@@ -1,23 +1,19 @@
-using System.ComponentModel.DataAnnotations;
 using System.ComponentModel.DataAnnotations.Schema;
 
 namespace Musify.Domain.Entities;
 
-#pragma warning disable CS8618
 [Table("UserHasTrack")]
 public class UserHasTrack
 {
     public Guid Id { get; set; } = Guid.NewGuid();
 
-    [Required]
     public required long UserId { get; set; }
 
-    [Required]
     public required Guid TrackId { get; set; }
 
     [ForeignKey(nameof(UserId))]
-    public User User { get; set; }
+    public User User { get; set; } = null!;
 
     [ForeignKey(nameof(TrackId))]
-    public Track Track { get; set; }
+    public Track Track { get; set; } = null!;
 }

backend/Core/Musify.Domain/ValueObjects/EntityPictures.cs

@@ -2,7 +2,8 @@ using System.ComponentModel.DataAnnotations;
 
 namespace Musify.Domain.ValueObjects;
 
-public class AlbumPictures
+/// <summary>The picture file names of an album or playlist. Resized names stay null until processing finishes.</summary>
+public class EntityPictures
 {
     [Required]
     public required string OriginalName { get; set; }
@@ -13,5 +14,5 @@ public class AlbumPictures
 
     public string? LargeName { get; set; }
 
-    public static AlbumPictures Pending(string originalName) => new() { OriginalName = originalName };
+    public static EntityPictures Pending(string objectName) => new() { OriginalName = objectName };
 }

backend/Core/Musify.Domain/ValueObjects/PlayListPictures.cs

@@ -1,17 +0,0 @@
-using System.ComponentModel.DataAnnotations;
-
-namespace Musify.Domain.ValueObjects;
-
-public class PlayListPictures
-{
-    [Required]
-    public required string OriginalName { get; set; }
-
-    public string? SmallName { get; set; }
-
-    public string? MediumName { get; set; }
-
-    public string? LargeName { get; set; }
-
-    public static PlayListPictures Pending(string originalName) => new() { OriginalName = originalName };
-}

backend/Core/Musify.Domain/ValueObjects/PlaylistVisibility.cs

@@ -1,6 +1,6 @@
 namespace Musify.Domain.ValueObjects;
 
-public enum PlaylistVisibility
+public enum PlayListVisibility
 {
     Private = 0,
     Public = 1

backend/Core/Musify.Infrastructure/MassTransit/Activities/Pictures/UpdateAlbumPictureActivity.cs

@@ -89,7 +89,7 @@ internal class UpdateAlbumPictureActivity(
                 return compensateContext.Compensated();
             }
 
-            album.Pictures = new AlbumPictures
+            album.Pictures = new EntityPictures
             {
                 OriginalName = compensateContext.Log.PreviousOriginalPictureKey,
                 SmallName = compensateContext.Log.PreviousSmallPictureKey,

backend/Core/Musify.Infrastructure/MassTransit/Activities/Pictures/UpdatePlayListPictureActivity.cs

@@ -89,7 +89,7 @@ internal class UpdatePlayListPictureActivity(
                 return compensateContext.Compensated();
             }
 
-            playList.Pictures = new PlayListPictures
+            playList.Pictures = new EntityPictures
             {
                 OriginalName = compensateContext.Log.PreviousOriginalPictureKey,
                 SmallName = compensateContext.Log.PreviousSmallPictureKey,

backend/Core/Musify.Infrastructure/Persistence/Database.cs

@@ -64,7 +64,7 @@ public class Database(DatabaseConfiguration configuration)
 
         modelBuilder.Entity<PlayList>()
             .Property(playList => playList.Visibility)
-            .HasDefaultValue(PlaylistVisibility.Private);
+            .HasDefaultValue(PlayListVisibility.Private);
 
         modelBuilder.Entity<PlayList>()
             .OwnsOne(playList => playList.Pictures, pictures =>

backend/Core/Musify.Infrastructure/Persistence/Migrations/DatabaseModelSnapshot.cs

@@ -379,12 +379,13 @@ namespace Musify.Infrastructure.Persistence.Migrations
                         .HasMaxLength(50)
                         .HasColumnType("character varying(50)");
 
+                    b.Property<long>("OwnerUserId")
+                        .HasColumnType("bigint")
+                        .HasColumnName("UserId");
+
                     b.Property<DateTime>("UpdatedAt")
                         .HasColumnType("timestamp with time zone");
 
-                    b.Property<long>("UserId")
-                        .HasColumnType("bigint");
-
                     b.Property<int>("Visibility")
                         .ValueGeneratedOnAdd()
                         .HasColumnType("integer")
@@ -392,7 +393,7 @@ namespace Musify.Infrastructure.Persistence.Migrations
 
                     b.HasKey("Id");
 
-                    b.HasIndex("UserId");
+                    b.HasIndex("OwnerUserId");
 
                     b.ToTable("PlayLists");
                 });
@@ -756,7 +757,7 @@ namespace Musify.Infrastructure.Persistence.Migrations
                         .OnDelete(DeleteBehavior.Restrict)
                         .IsRequired();
 
-                    b.OwnsOne("Musify.Domain.ValueObjects.AlbumPictures", "Pictures", b1 =>
+                    b.OwnsOne("Musify.Domain.ValueObjects.EntityPictures", "Pictures", b1 =>
                         {
                             b1.Property<Guid>("AlbumId")
                                 .HasColumnType("uuid");
@@ -865,13 +866,13 @@ namespace Musify.Infrastructure.Persistence.Migrations
 
             modelBuilder.Entity("Musify.Domain.Entities.PlayList", b =>
                 {
-                    b.HasOne("Musify.Domain.Entities.User", "User")
+                    b.HasOne("Musify.Domain.Entities.User", "Owner")
                         .WithMany("PlayLists")
-                        .HasForeignKey("UserId")
+                        .HasForeignKey("OwnerUserId")
                         .OnDelete(DeleteBehavior.Cascade)
                         .IsRequired();
 
-                    b.OwnsOne("Musify.Domain.ValueObjects.PlayListPictures", "Pictures", b1 =>
+                    b.OwnsOne("Musify.Domain.ValueObjects.EntityPictures", "Pictures", b1 =>
                         {
                             b1.Property<Guid>("PlayListId")
                                 .HasColumnType("uuid");
@@ -904,9 +905,9 @@ namespace Musify.Infrastructure.Persistence.Migrations
                                 .HasForeignKey("PlayListId");
                         });
 
-                    b.Navigation("Pictures");
+                    b.Navigation("Owner");
 
-                    b.Navigation("User");
+                    b.Navigation("Pictures");
                 });
 
             modelBuilder.Entity("Musify.Domain.Entities.PlayListHasTrack", b =>

backend/Hosts/Musify.Api/DataTransferObjects/PlayLists/CreatePlayListRequest.cs

@@ -6,4 +6,4 @@ public record CreatePlayListRequest(
     string Name,
     string? Description,
     Guid? PictureIntentId,
-    PlaylistVisibility Visibility = PlaylistVisibility.Private);
+    PlayListVisibility Visibility = PlayListVisibility.Private);

backend/Hosts/Musify.Api/DataTransferObjects/PlayLists/UpdatePlayListRequest.cs

@@ -6,4 +6,4 @@ public record UpdatePlayListRequest(
     string? NewName,
     string? NewDescription,
     Guid? NewPictureIntentId,
-    PlaylistVisibility? NewVisibility = null);
+    PlayListVisibility? NewVisibility = null);

backend/Tests/Musify.Application.Tests/Albums/GetAlbumCoverQueryHandlerTests.cs

@@ -39,7 +39,7 @@ public sealed class GetAlbumCoverQueryHandlerTests : HandlerTestBase
     public async Task Handle_PicturesStillProcessing_FallsBackToTheOriginal()
     {
         var owner = TestEntities.User();
-        var album = TestEntities.Album(owner.Id, pictures: Musify.Domain.ValueObjects.AlbumPictures.Pending("original.png"));
+        var album = TestEntities.Album(owner.Id, pictures: Musify.Domain.ValueObjects.EntityPictures.Pending("original.png"));
         await SeedAsync(owner, album);
 
         var result = await CreateHandler().Handle(new GetAlbumCoverQuery(album.Id, "small"), TestContext.Current.CancellationToken);

backend/Tests/Musify.Application.Tests/PlayLists/CreatePlayListCommandHandlerTests.cs

@@ -71,7 +71,7 @@ public sealed class CreatePlayListCommandHandlerTests : HandlerTestBase
         var result = await CreateHandler().Handle(command, TestContext.Current.CancellationToken);
 
         Assert.False(result.IsError);
-        Assert.Equal(Musify.Domain.ValueObjects.PlaylistVisibility.Private, result.Value.Visibility);
+        Assert.Equal(Musify.Domain.ValueObjects.PlayListVisibility.Private, result.Value.Visibility);
     }
 
     [Fact]
@@ -80,12 +80,12 @@ public sealed class CreatePlayListCommandHandlerTests : HandlerTestBase
         var user = TestEntities.User();
         await SeedAsync(user);
 
-        var command = new CreatePlayListCommand(user.Id, "My Playlist", null, PictureIntentId: null, Visibility: Musify.Domain.ValueObjects.PlaylistVisibility.Public);
+        var command = new CreatePlayListCommand(user.Id, "My Playlist", null, PictureIntentId: null, Visibility: Musify.Domain.ValueObjects.PlayListVisibility.Public);
 
         var result = await CreateHandler().Handle(command, TestContext.Current.CancellationToken);
 
         Assert.False(result.IsError);
-        Assert.Equal(Musify.Domain.ValueObjects.PlaylistVisibility.Public, result.Value.Visibility);
+        Assert.Equal(Musify.Domain.ValueObjects.PlayListVisibility.Public, result.Value.Visibility);
     }
 
     [Fact]

backend/Tests/Musify.Application.Tests/PlayLists/GetPlayListByIdQueryHandlerTests.cs

@@ -14,7 +14,7 @@ public sealed class GetPlayListByIdQueryHandlerTests : HandlerTestBase
     public async Task Handle_ExistingPlayList_ReturnsItWithCoverTrackIds()
     {
         var owner = TestEntities.User();
-        var playList = TestEntities.PlayList(owner.Id, visibility: Musify.Domain.ValueObjects.PlaylistVisibility.Public);
+        var playList = TestEntities.PlayList(owner.Id, visibility: Musify.Domain.ValueObjects.PlayListVisibility.Public);
         var track = TestEntities.Track(owner);
         await SeedAsync(owner, playList, track, new PlayListHasTrack { PlayListId = playList.Id, TrackId = track.Id, Position = 0 });
 
@@ -37,7 +37,7 @@ public sealed class GetPlayListByIdQueryHandlerTests : HandlerTestBase
     public async Task Handle_PrivatePlayList_RequestedByOwner_ReturnsIt()
     {
         var owner = TestEntities.User();
-        var playList = TestEntities.PlayList(owner.Id, visibility: Musify.Domain.ValueObjects.PlaylistVisibility.Private);
+        var playList = TestEntities.PlayList(owner.Id, visibility: Musify.Domain.ValueObjects.PlayListVisibility.Private);
         await SeedAsync(owner, playList);
 
         var result = await CreateHandler().Handle(new GetPlayListByIdQuery(playList.Id, owner.Id), TestContext.Current.CancellationToken);
@@ -50,7 +50,7 @@ public sealed class GetPlayListByIdQueryHandlerTests : HandlerTestBase
     {
         var owner = TestEntities.User(1, "owner");
         var stranger = TestEntities.User(2, "stranger");
-        var playList = TestEntities.PlayList(owner.Id, visibility: Musify.Domain.ValueObjects.PlaylistVisibility.Private);
+        var playList = TestEntities.PlayList(owner.Id, visibility: Musify.Domain.ValueObjects.PlayListVisibility.Private);
         await SeedAsync(owner, stranger, playList);
 
         var result = await CreateHandler().Handle(new GetPlayListByIdQuery(playList.Id, stranger.Id), TestContext.Current.CancellationToken);
@@ -62,7 +62,7 @@ public sealed class GetPlayListByIdQueryHandlerTests : HandlerTestBase
     public async Task Handle_PrivatePlayList_RequestedAnonymously_ReturnsNotFound()
     {
         var owner = TestEntities.User();
-        var playList = TestEntities.PlayList(owner.Id, visibility: Musify.Domain.ValueObjects.PlaylistVisibility.Private);
+        var playList = TestEntities.PlayList(owner.Id, visibility: Musify.Domain.ValueObjects.PlayListVisibility.Private);
         await SeedAsync(owner, playList);
 
         var result = await CreateHandler().Handle(new GetPlayListByIdQuery(playList.Id, RequestingUserId: null), TestContext.Current.CancellationToken);
@@ -74,7 +74,7 @@ public sealed class GetPlayListByIdQueryHandlerTests : HandlerTestBase
     public async Task Handle_PublicPlayList_RequestedAnonymously_ReturnsIt()
     {
         var owner = TestEntities.User();
-        var playList = TestEntities.PlayList(owner.Id, visibility: Musify.Domain.ValueObjects.PlaylistVisibility.Public);
+        var playList = TestEntities.PlayList(owner.Id, visibility: Musify.Domain.ValueObjects.PlayListVisibility.Public);
         await SeedAsync(owner, playList);
 
         var result = await CreateHandler().Handle(new GetPlayListByIdQuery(playList.Id, RequestingUserId: null), TestContext.Current.CancellationToken);

backend/Tests/Musify.Application.Tests/PlayLists/GetPlayListTracksQueryHandlerTests.cs

@@ -41,7 +41,7 @@ public sealed class GetPlayListTracksQueryHandlerTests : HandlerTestBase
     public async Task Handle_PrivatePlayListOfAnotherUser_ReturnsNotFound()
     {
         var owner = TestEntities.User();
-        var playList = TestEntities.PlayList(owner.Id, visibility: PlaylistVisibility.Private);
+        var playList = TestEntities.PlayList(owner.Id, visibility: PlayListVisibility.Private);
         await SeedAsync(owner, playList);
 
         var result = await CreateHandler().Handle(new GetPlayListTracksQuery(playList.Id, PageNumber: 1, PageSize: 10, ViewerId: 999), TestContext.Current.CancellationToken);
@@ -53,7 +53,7 @@ public sealed class GetPlayListTracksQueryHandlerTests : HandlerTestBase
     public async Task Handle_PrivatePlayListOfViewer_ReturnsTracks()
     {
         var owner = TestEntities.User();
-        var playList = TestEntities.PlayList(owner.Id, visibility: PlaylistVisibility.Private);
+        var playList = TestEntities.PlayList(owner.Id, visibility: PlayListVisibility.Private);
         await SeedAsync(owner, playList);
 
         var result = await CreateHandler().Handle(new GetPlayListTracksQuery(playList.Id, PageNumber: 1, PageSize: 10, ViewerId: owner.Id), TestContext.Current.CancellationToken);

backend/Tests/Musify.Application.Tests/PlayLists/GetPlayListsByUserIdQueryHandlerTests.cs

@@ -33,8 +33,8 @@ public sealed class GetPlayListsByUserIdQueryHandlerTests : HandlerTestBase
         var owner = TestEntities.User();
         await SeedAsync(
             owner,
-            TestEntities.PlayList(owner.Id, "Public one", visibility: PlaylistVisibility.Public),
+            TestEntities.PlayList(owner.Id, "Public one", visibility: PlayListVisibility.Public),
-            TestEntities.PlayList(owner.Id, "Private one", visibility: PlaylistVisibility.Private));
+            TestEntities.PlayList(owner.Id, "Private one", visibility: PlayListVisibility.Private));
 
         var result = await CreateHandler().Handle(new GetPlayListsByUserIdQuery(owner.Id, Name: null, PageNumber: 1, PageSize: 10, ViewerId: 999), TestContext.Current.CancellationToken);
 
@@ -49,8 +49,8 @@ public sealed class GetPlayListsByUserIdQueryHandlerTests : HandlerTestBase
         var owner = TestEntities.User();
         await SeedAsync(
             owner,
-            TestEntities.PlayList(owner.Id, "Public one", visibility: PlaylistVisibility.Public),
+            TestEntities.PlayList(owner.Id, "Public one", visibility: PlayListVisibility.Public),
-            TestEntities.PlayList(owner.Id, "Private one", visibility: PlaylistVisibility.Private));
+            TestEntities.PlayList(owner.Id, "Private one", visibility: PlayListVisibility.Private));
 
         var result = await CreateHandler().Handle(new GetPlayListsByUserIdQuery(owner.Id, Name: null, PageNumber: 1, PageSize: 10, ViewerId: owner.Id), TestContext.Current.CancellationToken);
 

backend/Tests/Musify.Application.Tests/PlayLists/UpdatePlayListCommandHandlerTests.cs

@@ -69,19 +69,19 @@ public sealed class UpdatePlayListCommandHandlerTests : HandlerTestBase
         var playList = TestEntities.PlayList(owner.Id);
         await SeedAsync(owner, playList);
 
-        var command = new UpdatePlayListCommand(owner.Id, playList.Id, null, null, null, Musify.Domain.ValueObjects.PlaylistVisibility.Public);
+        var command = new UpdatePlayListCommand(owner.Id, playList.Id, null, null, null, Musify.Domain.ValueObjects.PlayListVisibility.Public);
 
         var result = await CreateHandler().Handle(command, TestContext.Current.CancellationToken);
 
         Assert.False(result.IsError);
-        Assert.Equal(Musify.Domain.ValueObjects.PlaylistVisibility.Public, result.Value.Visibility);
+        Assert.Equal(Musify.Domain.ValueObjects.PlayListVisibility.Public, result.Value.Visibility);
     }
 
     [Fact]
     public async Task Handle_NoVisibilitySpecified_LeavesItUnchanged()
     {
         var owner = TestEntities.User();
-        var playList = TestEntities.PlayList(owner.Id, visibility: Musify.Domain.ValueObjects.PlaylistVisibility.Public);
+        var playList = TestEntities.PlayList(owner.Id, visibility: Musify.Domain.ValueObjects.PlayListVisibility.Public);
         await SeedAsync(owner, playList);
 
         var command = new UpdatePlayListCommand(owner.Id, playList.Id, "New Name", null, null);
@@ -89,7 +89,7 @@ public sealed class UpdatePlayListCommandHandlerTests : HandlerTestBase
         var result = await CreateHandler().Handle(command, TestContext.Current.CancellationToken);
 
         Assert.False(result.IsError);
-        Assert.Equal(Musify.Domain.ValueObjects.PlaylistVisibility.Public, result.Value.Visibility);
+        Assert.Equal(Musify.Domain.ValueObjects.PlayListVisibility.Public, result.Value.Visibility);
     }
 
     [Fact]

backend/Tests/Musify.Application.Tests/TestSupport/TestEntities.cs

@@ -79,7 +79,7 @@ public static class TestEntities
         return track;
     }
 
-    public static PlayListPictures PlayListPictures() => new()
+    public static EntityPictures PlayListPictures() => new()
     {
         OriginalName = "original.webp",
         SmallName = "small.webp",
@@ -91,12 +91,12 @@ public static class TestEntities
         long userId,
         string name = "Test Playlist",
         string? description = null,
-        PlayListPictures? pictures = null,
+        EntityPictures? pictures = null,
         LifeCycleStatus lifeCycleStatus = LifeCycleStatus.Active,
-        PlaylistVisibility visibility = PlaylistVisibility.Private) =>
+        PlayListVisibility visibility = PlayListVisibility.Private) =>
         new()
         {
-            UserId = userId,
+            OwnerUserId = userId,
             Name = name,
             NormalizedName = name.ToUpperInvariant(),
             Description = description,
@@ -105,7 +105,7 @@ public static class TestEntities
             Visibility = visibility
         };
 
-    public static AlbumPictures AlbumPictures() => new()
+    public static EntityPictures AlbumPictures() => new()
     {
         OriginalName = "original.webp",
         SmallName = "small.webp",
@@ -118,7 +118,7 @@ public static class TestEntities
         string title = "Test Album",
         string? description = null,
         int? releaseYear = 2024,
-        AlbumPictures? pictures = null) =>
+        EntityPictures? pictures = null) =>
         new()
         {
             Title = title,