[FA-27] Need to test events but seems to mostly work

FictionArchive.Service.NovelService/Models/IntegrationEvents/ChapterCreatedEvent.cs

@@ -0,0 +1,13 @@
+using FictionArchive.Service.Shared.Services.EventBus;
+
+namespace FictionArchive.Service.NovelService.Models.IntegrationEvents;
+
+public class ChapterCreatedEvent : IIntegrationEvent
+{
+    public required uint ChapterId { get; init; }
+    public required uint NovelId { get; init; }
+    public required uint VolumeId { get; init; }
+    public required int VolumeOrder { get; init; }
+    public required uint ChapterOrder { get; init; }
+    public required string ChapterTitle { get; init; }
+}

FictionArchive.Service.NovelService/Models/IntegrationEvents/NovelCreatedEvent.cs

@@ -0,0 +1,13 @@
+using FictionArchive.Common.Enums;
+using FictionArchive.Service.Shared.Services.EventBus;
+
+namespace FictionArchive.Service.NovelService.Models.IntegrationEvents;
+
+public class NovelCreatedEvent : IIntegrationEvent
+{
+    public required uint NovelId { get; init; }
+    public required string Title { get; init; }
+    public required Language OriginalLanguage { get; init; }
+    public required string Source { get; init; }
+    public required string AuthorName { get; init; }
+}

FictionArchive.Service.NovelService/Services/NovelUpdateService.cs

@@ -343,6 +343,12 @@ public class NovelUpdateService
         Novel novel;
         bool shouldPublishCoverEvent;
 
+        // Capture existing chapter IDs to detect new chapters later
+        var existingChapterIds = existingNovel?.Volumes
+            .SelectMany(v => v.Chapters)
+            .Select(c => c.Id)
+            .ToHashSet() ?? new HashSet<uint>();
+
         if (existingNovel == null)
         {
             // CREATE PATH: New novel
@@ -384,6 +390,36 @@ public class NovelUpdateService
 
         await _dbContext.SaveChangesAsync();
 
+        // Publish novel created event for new novels
+        if (existingNovel == null)
+        {
+            await _eventBus.Publish(new NovelCreatedEvent
+            {
+                NovelId = novel.Id,
+                Title = novel.Name.Texts.First(t => t.Language == novel.RawLanguage).Text,
+                OriginalLanguage = novel.RawLanguage,
+                Source = novel.Source.Key,
+                AuthorName = novel.Author.Name.Texts.First(t => t.Language == novel.RawLanguage).Text
+            });
+        }
+
+        // Publish chapter created events for new chapters
+        foreach (var volume in novel.Volumes)
+        {
+            foreach (var chapter in volume.Chapters.Where(c => !existingChapterIds.Contains(c.Id)))
+            {
+                await _eventBus.Publish(new ChapterCreatedEvent
+                {
+                    ChapterId = chapter.Id,
+                    NovelId = novel.Id,
+                    VolumeId = volume.Id,
+                    VolumeOrder = volume.Order,
+                    ChapterOrder = chapter.Order,
+                    ChapterTitle = chapter.Name.Texts.First(t => t.Language == novel.RawLanguage).Text
+                });
+            }
+        }
+
         // Publish cover image event if needed
         if (shouldPublishCoverEvent && novel.CoverImage != null && metadata.CoverImage != null)
         {

FictionArchive.Service.UserNovelDataService/Migrations/20260119184741_AddNovelVolumeChapter.Designer.cs

@@ -0,0 +1,198 @@
+// <auto-generated />
+using System;
+using FictionArchive.Service.UserNovelDataService.Services;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using NodaTime;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+
+#nullable disable
+
+namespace FictionArchive.Service.UserNovelDataService.Migrations
+{
+    [DbContext(typeof(UserNovelDataServiceDbContext))]
+    [Migration("20260119184741_AddNovelVolumeChapter")]
+    partial class AddNovelVolumeChapter
+    {
+        /// <inheritdoc />
+        protected override void BuildTargetModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("ProductVersion", "9.0.11")
+                .HasAnnotation("Relational:MaxIdentifierLength", 63);
+
+            NpgsqlModelBuilderExtensions.UseIdentityByDefaultColumns(modelBuilder);
+
+            modelBuilder.Entity("FictionArchive.Service.UserNovelDataService.Models.Database.Bookmark", b =>
+                {
+                    b.Property<int>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("Id"));
+
+                    b.Property<long>("ChapterId")
+                        .HasColumnType("bigint");
+
+                    b.Property<Instant>("CreatedTime")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.Property<string>("Description")
+                        .HasColumnType("text");
+
+                    b.Property<Instant>("LastUpdatedTime")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.Property<long>("NovelId")
+                        .HasColumnType("bigint");
+
+                    b.Property<Guid>("UserId")
+                        .HasColumnType("uuid");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("UserId", "ChapterId")
+                        .IsUnique();
+
+                    b.HasIndex("UserId", "NovelId");
+
+                    b.ToTable("Bookmarks");
+                });
+
+            modelBuilder.Entity("FictionArchive.Service.UserNovelDataService.Models.Database.Chapter", b =>
+                {
+                    b.Property<long>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("bigint");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<long>("Id"));
+
+                    b.Property<Instant>("CreatedTime")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.Property<Instant>("LastUpdatedTime")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.Property<long>("VolumeId")
+                        .HasColumnType("bigint");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("VolumeId");
+
+                    b.ToTable("Chapters");
+                });
+
+            modelBuilder.Entity("FictionArchive.Service.UserNovelDataService.Models.Database.Novel", b =>
+                {
+                    b.Property<long>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("bigint");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<long>("Id"));
+
+                    b.Property<Instant>("CreatedTime")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.Property<Instant>("LastUpdatedTime")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.HasKey("Id");
+
+                    b.ToTable("Novels");
+                });
+
+            modelBuilder.Entity("FictionArchive.Service.UserNovelDataService.Models.Database.User", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("uuid");
+
+                    b.Property<Instant>("CreatedTime")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.Property<Instant>("LastUpdatedTime")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.Property<string>("OAuthProviderId")
+                        .IsRequired()
+                        .HasColumnType("text");
+
+                    b.HasKey("Id");
+
+                    b.ToTable("Users");
+                });
+
+            modelBuilder.Entity("FictionArchive.Service.UserNovelDataService.Models.Database.Volume", b =>
+                {
+                    b.Property<long>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("bigint");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<long>("Id"));
+
+                    b.Property<Instant>("CreatedTime")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.Property<Instant>("LastUpdatedTime")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.Property<long>("NovelId")
+                        .HasColumnType("bigint");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("NovelId");
+
+                    b.ToTable("Volumes");
+                });
+
+            modelBuilder.Entity("FictionArchive.Service.UserNovelDataService.Models.Database.Bookmark", b =>
+                {
+                    b.HasOne("FictionArchive.Service.UserNovelDataService.Models.Database.User", "User")
+                        .WithMany()
+                        .HasForeignKey("UserId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.Navigation("User");
+                });
+
+            modelBuilder.Entity("FictionArchive.Service.UserNovelDataService.Models.Database.Chapter", b =>
+                {
+                    b.HasOne("FictionArchive.Service.UserNovelDataService.Models.Database.Volume", "Volume")
+                        .WithMany("Chapters")
+                        .HasForeignKey("VolumeId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.Navigation("Volume");
+                });
+
+            modelBuilder.Entity("FictionArchive.Service.UserNovelDataService.Models.Database.Volume", b =>
+                {
+                    b.HasOne("FictionArchive.Service.UserNovelDataService.Models.Database.Novel", "Novel")
+                        .WithMany("Volumes")
+                        .HasForeignKey("NovelId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.Navigation("Novel");
+                });
+
+            modelBuilder.Entity("FictionArchive.Service.UserNovelDataService.Models.Database.Novel", b =>
+                {
+                    b.Navigation("Volumes");
+                });
+
+            modelBuilder.Entity("FictionArchive.Service.UserNovelDataService.Models.Database.Volume", b =>
+                {
+                    b.Navigation("Chapters");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}

FictionArchive.Service.UserNovelDataService/Migrations/20260119184741_AddNovelVolumeChapter.cs

@@ -0,0 +1,95 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+using NodaTime;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+
+#nullable disable
+
+namespace FictionArchive.Service.UserNovelDataService.Migrations
+{
+    /// <inheritdoc />
+    public partial class AddNovelVolumeChapter : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.CreateTable(
+                name: "Novels",
+                columns: table => new
+                {
+                    Id = table.Column<long>(type: "bigint", nullable: false)
+                        .Annotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.IdentityByDefaultColumn),
+                    CreatedTime = table.Column<Instant>(type: "timestamp with time zone", nullable: false),
+                    LastUpdatedTime = table.Column<Instant>(type: "timestamp with time zone", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_Novels", x => x.Id);
+                });
+
+            migrationBuilder.CreateTable(
+                name: "Volumes",
+                columns: table => new
+                {
+                    Id = table.Column<long>(type: "bigint", nullable: false)
+                        .Annotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.IdentityByDefaultColumn),
+                    NovelId = table.Column<long>(type: "bigint", nullable: false),
+                    CreatedTime = table.Column<Instant>(type: "timestamp with time zone", nullable: false),
+                    LastUpdatedTime = table.Column<Instant>(type: "timestamp with time zone", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_Volumes", x => x.Id);
+                    table.ForeignKey(
+                        name: "FK_Volumes_Novels_NovelId",
+                        column: x => x.NovelId,
+                        principalTable: "Novels",
+                        principalColumn: "Id",
+                        onDelete: ReferentialAction.Cascade);
+                });
+
+            migrationBuilder.CreateTable(
+                name: "Chapters",
+                columns: table => new
+                {
+                    Id = table.Column<long>(type: "bigint", nullable: false)
+                        .Annotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.IdentityByDefaultColumn),
+                    VolumeId = table.Column<long>(type: "bigint", nullable: false),
+                    CreatedTime = table.Column<Instant>(type: "timestamp with time zone", nullable: false),
+                    LastUpdatedTime = table.Column<Instant>(type: "timestamp with time zone", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_Chapters", x => x.Id);
+                    table.ForeignKey(
+                        name: "FK_Chapters_Volumes_VolumeId",
+                        column: x => x.VolumeId,
+                        principalTable: "Volumes",
+                        principalColumn: "Id",
+                        onDelete: ReferentialAction.Cascade);
+                });
+
+            migrationBuilder.CreateIndex(
+                name: "IX_Chapters_VolumeId",
+                table: "Chapters",
+                column: "VolumeId");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_Volumes_NovelId",
+                table: "Volumes",
+                column: "NovelId");
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "Chapters");
+
+            migrationBuilder.DropTable(
+                name: "Volumes");
+
+            migrationBuilder.DropTable(
+                name: "Novels");
+        }
+    }
+}

FictionArchive.Service.UserNovelDataService/Migrations/UserNovelDataServiceDbContextModelSnapshot.cs

@@ -59,6 +59,49 @@ namespace FictionArchive.Service.UserNovelDataService.Migrations
                     b.ToTable("Bookmarks");
                 });
 
+            modelBuilder.Entity("FictionArchive.Service.UserNovelDataService.Models.Database.Chapter", b =>
+                {
+                    b.Property<long>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("bigint");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<long>("Id"));
+
+                    b.Property<Instant>("CreatedTime")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.Property<Instant>("LastUpdatedTime")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.Property<long>("VolumeId")
+                        .HasColumnType("bigint");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("VolumeId");
+
+                    b.ToTable("Chapters");
+                });
+
+            modelBuilder.Entity("FictionArchive.Service.UserNovelDataService.Models.Database.Novel", b =>
+                {
+                    b.Property<long>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("bigint");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<long>("Id"));
+
+                    b.Property<Instant>("CreatedTime")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.Property<Instant>("LastUpdatedTime")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.HasKey("Id");
+
+                    b.ToTable("Novels");
+                });
+
             modelBuilder.Entity("FictionArchive.Service.UserNovelDataService.Models.Database.User", b =>
                 {
                     b.Property<Guid>("Id")
@@ -80,6 +123,30 @@ namespace FictionArchive.Service.UserNovelDataService.Migrations
                     b.ToTable("Users");
                 });
 
+            modelBuilder.Entity("FictionArchive.Service.UserNovelDataService.Models.Database.Volume", b =>
+                {
+                    b.Property<long>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("bigint");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<long>("Id"));
+
+                    b.Property<Instant>("CreatedTime")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.Property<Instant>("LastUpdatedTime")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.Property<long>("NovelId")
+                        .HasColumnType("bigint");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("NovelId");
+
+                    b.ToTable("Volumes");
+                });
+
             modelBuilder.Entity("FictionArchive.Service.UserNovelDataService.Models.Database.Bookmark", b =>
                 {
                     b.HasOne("FictionArchive.Service.UserNovelDataService.Models.Database.User", "User")
@@ -90,6 +157,38 @@ namespace FictionArchive.Service.UserNovelDataService.Migrations
 
                     b.Navigation("User");
                 });
+
+            modelBuilder.Entity("FictionArchive.Service.UserNovelDataService.Models.Database.Chapter", b =>
+                {
+                    b.HasOne("FictionArchive.Service.UserNovelDataService.Models.Database.Volume", "Volume")
+                        .WithMany("Chapters")
+                        .HasForeignKey("VolumeId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.Navigation("Volume");
+                });
+
+            modelBuilder.Entity("FictionArchive.Service.UserNovelDataService.Models.Database.Volume", b =>
+                {
+                    b.HasOne("FictionArchive.Service.UserNovelDataService.Models.Database.Novel", "Novel")
+                        .WithMany("Volumes")
+                        .HasForeignKey("NovelId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.Navigation("Novel");
+                });
+
+            modelBuilder.Entity("FictionArchive.Service.UserNovelDataService.Models.Database.Novel", b =>
+                {
+                    b.Navigation("Volumes");
+                });
+
+            modelBuilder.Entity("FictionArchive.Service.UserNovelDataService.Models.Database.Volume", b =>
+                {
+                    b.Navigation("Chapters");
+                });
 #pragma warning restore 612, 618
         }
     }

FictionArchive.Service.UserNovelDataService/Models/Database/Chapter.cs

@@ -4,5 +4,6 @@ namespace FictionArchive.Service.UserNovelDataService.Models.Database;
 
 public class Chapter : BaseEntity<uint>
 {
-    
+    public uint VolumeId { get; set; }
+    public virtual Volume Volume { get; set; } = null!;
 }

FictionArchive.Service.UserNovelDataService/Models/Database/Novel.cs

@@ -4,5 +4,5 @@ namespace FictionArchive.Service.UserNovelDataService.Models.Database;
 
 public class Novel : BaseEntity<uint>
 {
-    public virtual ICollection<Volume> Volumes { get; set; }
+    public virtual ICollection<Volume> Volumes { get; set; } = new List<Volume>();
 }

FictionArchive.Service.UserNovelDataService/Models/Database/Volume.cs

@@ -4,5 +4,7 @@ namespace FictionArchive.Service.UserNovelDataService.Models.Database;
 
 public class Volume : BaseEntity<uint>
 {
-    public virtual ICollection<Chapter> Chapters { get; set; }
+    public uint NovelId { get; set; }
+    public virtual Novel Novel { get; set; } = null!;
+    public virtual ICollection<Chapter> Chapters { get; set; } = new List<Chapter>();
 }

FictionArchive.Service.UserNovelDataService/Models/IntegrationEvents/ChapterCreatedEvent.cs

@@ -0,0 +1,13 @@
+using FictionArchive.Service.Shared.Services.EventBus;
+
+namespace FictionArchive.Service.UserNovelDataService.Models.IntegrationEvents;
+
+public class ChapterCreatedEvent : IIntegrationEvent
+{
+    public required uint ChapterId { get; init; }
+    public required uint NovelId { get; init; }
+    public required uint VolumeId { get; init; }
+    public required int VolumeOrder { get; init; }
+    public required uint ChapterOrder { get; init; }
+    public required string ChapterTitle { get; init; }
+}

FictionArchive.Service.UserNovelDataService/Models/IntegrationEvents/NovelCreatedEvent.cs

@@ -0,0 +1,13 @@
+using FictionArchive.Common.Enums;
+using FictionArchive.Service.Shared.Services.EventBus;
+
+namespace FictionArchive.Service.UserNovelDataService.Models.IntegrationEvents;
+
+public class NovelCreatedEvent : IIntegrationEvent
+{
+    public required uint NovelId { get; init; }
+    public required string Title { get; init; }
+    public required Language OriginalLanguage { get; init; }
+    public required string Source { get; init; }
+    public required string AuthorName { get; init; }
+}

FictionArchive.Service.UserNovelDataService/Models/IntegrationEvents/UserInvitedEvent.cs

@@ -0,0 +1,15 @@
+using FictionArchive.Service.Shared.Services.EventBus;
+
+namespace FictionArchive.Service.UserNovelDataService.Models.IntegrationEvents;
+
+public class UserInvitedEvent : IIntegrationEvent
+{
+    public Guid InvitedUserId { get; set; }
+    public required string InvitedUsername { get; set; }
+    public required string InvitedEmail { get; set; }
+    public required string InvitedOAuthProviderId { get; set; }
+
+    public Guid InviterId { get; set; }
+    public required string InviterUsername { get; set; }
+    public required string InviterOAuthProviderId { get; set; }
+}

FictionArchive.Service.UserNovelDataService/Program.cs

@@ -3,7 +3,9 @@ using FictionArchive.Service.Shared;
 using FictionArchive.Service.Shared.Extensions;
 using FictionArchive.Service.Shared.Services.EventBus.Implementations;
 using FictionArchive.Service.UserNovelDataService.GraphQL;
+using FictionArchive.Service.UserNovelDataService.Models.IntegrationEvents;
 using FictionArchive.Service.UserNovelDataService.Services;
+using FictionArchive.Service.UserNovelDataService.Services.EventHandlers;
 
 namespace FictionArchive.Service.UserNovelDataService;
 
@@ -27,7 +29,10 @@ public class Program
             builder.Services.AddRabbitMQ(opt =>
             {
                 builder.Configuration.GetSection("RabbitMQ").Bind(opt);
-            });
+            })
+                .Subscribe<NovelCreatedEvent, NovelCreatedEventHandler>()
+                .Subscribe<ChapterCreatedEvent, ChapterCreatedEventHandler>()
+                .Subscribe<UserInvitedEvent, UserInvitedEventHandler>();
         }
 
         #endregion

FictionArchive.Service.UserNovelDataService/Scripts/00_README.md

@@ -0,0 +1,93 @@
+# UserNovelDataService Backfill Scripts
+
+SQL scripts for backfilling data from UserService and NovelService into UserNovelDataService.
+
+## Prerequisites
+
+1. **Run EF migrations** on the UserNovelDataService database to ensure all tables exist:
+   ```bash
+   dotnet ef database update --project FictionArchive.Service.UserNovelDataService
+   ```
+
+   This will apply the `AddNovelVolumeChapter` migration which creates:
+   - `Novels` table (Id, CreatedTime, LastUpdatedTime)
+   - `Volumes` table (Id, NovelId FK, CreatedTime, LastUpdatedTime)
+   - `Chapters` table (Id, VolumeId FK, CreatedTime, LastUpdatedTime)
+
+## Execution Order
+
+Run scripts in numeric order:
+
+### Extraction (run against source databases)
+1. `01_extract_users_from_userservice.sql` - Run against **UserService** DB
+2. `02_extract_novels_from_novelservice.sql` - Run against **NovelService** DB
+3. `03_extract_volumes_from_novelservice.sql` - Run against **NovelService** DB
+4. `04_extract_chapters_from_novelservice.sql` - Run against **NovelService** DB
+
+### Insertion (run against UserNovelDataService database)
+5. `05_insert_users_to_usernoveldataservice.sql`
+6. `06_insert_novels_to_usernoveldataservice.sql`
+7. `07_insert_volumes_to_usernoveldataservice.sql`
+8. `08_insert_chapters_to_usernoveldataservice.sql`
+
+## Methods
+
+Each script provides three options:
+
+1. **SELECT for review** - Review data before export
+2. **Generate INSERT statements** - Creates individual INSERT statements (good for small datasets)
+3. **CSV export/import** - Use PostgreSQL `\copy` for bulk operations (recommended for large datasets)
+
+## Example Workflow
+
+### Using CSV Export/Import (Recommended)
+
+```bash
+# 1. Export from source databases
+psql -h localhost -U postgres -d userservice -c "\copy (SELECT \"Id\", \"OAuthProviderId\", \"CreatedTime\", \"LastUpdatedTime\" FROM \"Users\" WHERE \"Disabled\" = false) TO '/tmp/users_export.csv' WITH CSV HEADER"
+
+psql -h localhost -U postgres -d novelservice -c "\copy (SELECT \"Id\", \"CreatedTime\", \"LastUpdatedTime\" FROM \"Novels\") TO '/tmp/novels_export.csv' WITH CSV HEADER"
+
+psql -h localhost -U postgres -d novelservice -c "\copy (SELECT \"Id\", \"NovelId\", \"CreatedTime\", \"LastUpdatedTime\" FROM \"Volume\" ORDER BY \"NovelId\", \"Id\") TO '/tmp/volumes_export.csv' WITH CSV HEADER"
+
+psql -h localhost -U postgres -d novelservice -c "\copy (SELECT \"Id\", \"VolumeId\", \"CreatedTime\", \"LastUpdatedTime\" FROM \"Chapter\" ORDER BY \"VolumeId\", \"Id\") TO '/tmp/chapters_export.csv' WITH CSV HEADER"
+
+# 2. Import into UserNovelDataService (order matters due to FK constraints!)
+psql -h localhost -U postgres -d usernoveldataservice -c "\copy \"Users\" (\"Id\", \"OAuthProviderId\", \"CreatedTime\", \"LastUpdatedTime\") FROM '/tmp/users_export.csv' WITH CSV HEADER"
+
+psql -h localhost -U postgres -d usernoveldataservice -c "\copy \"Novels\" (\"Id\", \"CreatedTime\", \"LastUpdatedTime\") FROM '/tmp/novels_export.csv' WITH CSV HEADER"
+
+psql -h localhost -U postgres -d usernoveldataservice -c "\copy \"Volumes\" (\"Id\", \"NovelId\", \"CreatedTime\", \"LastUpdatedTime\") FROM '/tmp/volumes_export.csv' WITH CSV HEADER"
+
+psql -h localhost -U postgres -d usernoveldataservice -c "\copy \"Chapters\" (\"Id\", \"VolumeId\", \"CreatedTime\", \"LastUpdatedTime\") FROM '/tmp/chapters_export.csv' WITH CSV HEADER"
+```
+
+**Important**: Insert order matters due to foreign key constraints:
+1. Users (no dependencies)
+2. Novels (no dependencies)
+3. Volumes (depends on Novels)
+4. Chapters (depends on Volumes)
+
+### Using dblink (Cross-database queries)
+
+If both databases are on the same PostgreSQL server, you can use `dblink` extension for direct cross-database inserts. See the commented examples in each insert script.
+
+## Verification
+
+After running the backfill, verify counts match:
+
+```sql
+-- Run on UserService DB
+SELECT COUNT(*) as user_count FROM "Users" WHERE "Disabled" = false;
+
+-- Run on NovelService DB
+SELECT COUNT(*) as novel_count FROM "Novels";
+SELECT COUNT(*) as volume_count FROM "Volume";
+SELECT COUNT(*) as chapter_count FROM "Chapter";
+
+-- Run on UserNovelDataService DB
+SELECT COUNT(*) as user_count FROM "Users";
+SELECT COUNT(*) as novel_count FROM "Novels";
+SELECT COUNT(*) as volume_count FROM "Volumes";
+SELECT COUNT(*) as chapter_count FROM "Chapters";
+```

FictionArchive.Service.UserNovelDataService/Scripts/01_extract_users_from_userservice.sql

@@ -0,0 +1,28 @@
+-- Extract Users from UserService database
+-- Run this against: UserService PostgreSQL database
+-- Output: CSV or use COPY TO for bulk export
+
+-- Option 1: Simple SELECT for review/testing
+SELECT
+    "Id",
+    "OAuthProviderId",
+    "CreatedTime",
+    "LastUpdatedTime"
+FROM "Users"
+WHERE "Disabled" = false
+ORDER BY "CreatedTime";
+
+-- Option 2: Generate INSERT statements (useful for small datasets)
+SELECT format(
+    'INSERT INTO "Users" ("Id", "OAuthProviderId", "CreatedTime", "LastUpdatedTime") VALUES (%L, %L, %L, %L) ON CONFLICT ("Id") DO NOTHING;',
+    "Id",
+    "OAuthProviderId",
+    "CreatedTime",
+    "LastUpdatedTime"
+)
+FROM "Users"
+WHERE "Disabled" = false
+ORDER BY "CreatedTime";
+
+-- Option 3: Export to CSV (run from psql)
+-- \copy (SELECT "Id", "OAuthProviderId", "CreatedTime", "LastUpdatedTime" FROM "Users" WHERE "Disabled" = false ORDER BY "CreatedTime") TO '/tmp/users_export.csv' WITH CSV HEADER;

FictionArchive.Service.UserNovelDataService/Scripts/02_extract_novels_from_novelservice.sql

@@ -0,0 +1,24 @@
+-- Extract Novels from NovelService database
+-- Run this against: NovelService PostgreSQL database
+-- Output: CSV or use COPY TO for bulk export
+
+-- Option 1: Simple SELECT for review/testing
+SELECT
+    "Id",
+    "CreatedTime",
+    "LastUpdatedTime"
+FROM "Novels"
+ORDER BY "Id";
+
+-- Option 2: Generate INSERT statements
+SELECT format(
+    'INSERT INTO "Novels" ("Id", "CreatedTime", "LastUpdatedTime") VALUES (%s, %L, %L) ON CONFLICT ("Id") DO NOTHING;',
+    "Id",
+    "CreatedTime",
+    "LastUpdatedTime"
+)
+FROM "Novels"
+ORDER BY "Id";
+
+-- Option 3: Export to CSV (run from psql)
+-- \copy (SELECT "Id", "CreatedTime", "LastUpdatedTime" FROM "Novels" ORDER BY "Id") TO '/tmp/novels_export.csv' WITH CSV HEADER;

FictionArchive.Service.UserNovelDataService/Scripts/03_extract_volumes_from_novelservice.sql

@@ -0,0 +1,26 @@
+-- Extract Volumes from NovelService database
+-- Run this against: NovelService PostgreSQL database
+-- Output: CSV or use COPY TO for bulk export
+
+-- Option 1: Simple SELECT for review/testing
+SELECT
+    "Id",
+    "NovelId",
+    "CreatedTime",
+    "LastUpdatedTime"
+FROM "Volume"
+ORDER BY "NovelId", "Id";
+
+-- Option 2: Generate INSERT statements
+SELECT format(
+    'INSERT INTO "Volumes" ("Id", "NovelId", "CreatedTime", "LastUpdatedTime") VALUES (%s, %s, %L, %L) ON CONFLICT ("Id") DO NOTHING;',
+    "Id",
+    "NovelId",
+    "CreatedTime",
+    "LastUpdatedTime"
+)
+FROM "Volume"
+ORDER BY "NovelId", "Id";
+
+-- Option 3: Export to CSV (run from psql)
+-- \copy (SELECT "Id", "NovelId", "CreatedTime", "LastUpdatedTime" FROM "Volume" ORDER BY "NovelId", "Id") TO '/tmp/volumes_export.csv' WITH CSV HEADER;

FictionArchive.Service.UserNovelDataService/Scripts/04_extract_chapters_from_novelservice.sql

@@ -0,0 +1,26 @@
+-- Extract Chapters from NovelService database
+-- Run this against: NovelService PostgreSQL database
+-- Output: CSV or use COPY TO for bulk export
+
+-- Option 1: Simple SELECT for review/testing
+SELECT
+    "Id",
+    "VolumeId",
+    "CreatedTime",
+    "LastUpdatedTime"
+FROM "Chapter"
+ORDER BY "VolumeId", "Id";
+
+-- Option 2: Generate INSERT statements
+SELECT format(
+    'INSERT INTO "Chapters" ("Id", "VolumeId", "CreatedTime", "LastUpdatedTime") VALUES (%s, %s, %L, %L) ON CONFLICT ("Id") DO NOTHING;',
+    "Id",
+    "VolumeId",
+    "CreatedTime",
+    "LastUpdatedTime"
+)
+FROM "Chapter"
+ORDER BY "VolumeId", "Id";
+
+-- Option 3: Export to CSV (run from psql)
+-- \copy (SELECT "Id", "VolumeId", "CreatedTime", "LastUpdatedTime" FROM "Chapter" ORDER BY "VolumeId", "Id") TO '/tmp/chapters_export.csv' WITH CSV HEADER;

FictionArchive.Service.UserNovelDataService/Scripts/05_insert_users_to_usernoveldataservice.sql

@@ -0,0 +1,32 @@
+-- Insert Users into UserNovelDataService database
+-- Run this against: UserNovelDataService PostgreSQL database
+--
+-- PREREQUISITE: You must have extracted users from UserService first
+-- using 01_extract_users_from_userservice.sql
+
+-- Option 1: If you have a CSV file from export
+-- \copy "Users" ("Id", "OAuthProviderId", "CreatedTime", "LastUpdatedTime") FROM '/tmp/users_export.csv' WITH CSV HEADER;
+
+-- Option 2: Direct cross-database insert using dblink
+-- First, install dblink extension if not already done:
+-- CREATE EXTENSION IF NOT EXISTS dblink;
+
+-- Example using dblink (adjust connection string):
+/*
+INSERT INTO "Users" ("Id", "OAuthProviderId", "CreatedTime", "LastUpdatedTime")
+SELECT
+    "Id"::uuid,
+    "OAuthProviderId",
+    "CreatedTime"::timestamp with time zone,
+    "LastUpdatedTime"::timestamp with time zone
+FROM dblink(
+    'host=localhost port=5432 dbname=userservice user=postgres password=yourpassword',
+    'SELECT "Id", "OAuthProviderId", "CreatedTime", "LastUpdatedTime" FROM "Users" WHERE "Disabled" = false'
+) AS t("Id" uuid, "OAuthProviderId" text, "CreatedTime" timestamp with time zone, "LastUpdatedTime" timestamp with time zone)
+ON CONFLICT ("Id") DO UPDATE SET
+    "OAuthProviderId" = EXCLUDED."OAuthProviderId",
+    "LastUpdatedTime" = EXCLUDED."LastUpdatedTime";
+*/
+
+-- Option 3: Paste generated INSERT statements from extraction script here
+-- INSERT INTO "Users" ("Id", "OAuthProviderId", "CreatedTime", "LastUpdatedTime") VALUES (...) ON CONFLICT ("Id") DO NOTHING;

FictionArchive.Service.UserNovelDataService/Scripts/06_insert_novels_to_usernoveldataservice.sql

@@ -0,0 +1,31 @@
+-- Insert Novels into UserNovelDataService database
+-- Run this against: UserNovelDataService PostgreSQL database
+--
+-- PREREQUISITE:
+-- 1. Ensure the Novels table exists (run EF migrations first if needed)
+-- 2. Extract novels from NovelService using 02_extract_novels_from_novelservice.sql
+
+-- Option 1: If you have a CSV file from export
+-- \copy "Novels" ("Id", "CreatedTime", "LastUpdatedTime") FROM '/tmp/novels_export.csv' WITH CSV HEADER;
+
+-- Option 2: Direct cross-database insert using dblink
+-- First, install dblink extension if not already done:
+-- CREATE EXTENSION IF NOT EXISTS dblink;
+
+-- Example using dblink (adjust connection string):
+/*
+INSERT INTO "Novels" ("Id", "CreatedTime", "LastUpdatedTime")
+SELECT
+    "Id"::bigint,
+    "CreatedTime"::timestamp with time zone,
+    "LastUpdatedTime"::timestamp with time zone
+FROM dblink(
+    'host=localhost port=5432 dbname=novelservice user=postgres password=yourpassword',
+    'SELECT "Id", "CreatedTime", "LastUpdatedTime" FROM "Novels"'
+) AS t("Id" bigint, "CreatedTime" timestamp with time zone, "LastUpdatedTime" timestamp with time zone)
+ON CONFLICT ("Id") DO UPDATE SET
+    "LastUpdatedTime" = EXCLUDED."LastUpdatedTime";
+*/
+
+-- Option 3: Paste generated INSERT statements from extraction script here
+-- INSERT INTO "Novels" ("Id", "CreatedTime", "LastUpdatedTime") VALUES (...) ON CONFLICT ("Id") DO NOTHING;

FictionArchive.Service.UserNovelDataService/Scripts/07_insert_volumes_to_usernoveldataservice.sql

@@ -0,0 +1,34 @@
+-- Insert Volumes into UserNovelDataService database
+-- Run this against: UserNovelDataService PostgreSQL database
+--
+-- PREREQUISITE:
+-- 1. Ensure the Volumes table exists (run EF migrations first if needed)
+-- 2. Novels must be inserted first (FK constraint)
+-- 3. Extract volumes from NovelService using 03_extract_volumes_from_novelservice.sql
+
+-- Option 1: If you have a CSV file from export
+-- \copy "Volumes" ("Id", "NovelId", "CreatedTime", "LastUpdatedTime") FROM '/tmp/volumes_export.csv' WITH CSV HEADER;
+
+-- Option 2: Direct cross-database insert using dblink
+-- First, install dblink extension if not already done:
+-- CREATE EXTENSION IF NOT EXISTS dblink;
+
+-- Example using dblink (adjust connection string):
+/*
+INSERT INTO "Volumes" ("Id", "NovelId", "CreatedTime", "LastUpdatedTime")
+SELECT
+    "Id"::bigint,
+    "NovelId"::bigint,
+    "CreatedTime"::timestamp with time zone,
+    "LastUpdatedTime"::timestamp with time zone
+FROM dblink(
+    'host=localhost port=5432 dbname=novelservice user=postgres password=yourpassword',
+    'SELECT "Id", "NovelId", "CreatedTime", "LastUpdatedTime" FROM "Volume"'
+) AS t("Id" bigint, "NovelId" bigint, "CreatedTime" timestamp with time zone, "LastUpdatedTime" timestamp with time zone)
+ON CONFLICT ("Id") DO UPDATE SET
+    "NovelId" = EXCLUDED."NovelId",
+    "LastUpdatedTime" = EXCLUDED."LastUpdatedTime";
+*/
+
+-- Option 3: Paste generated INSERT statements from extraction script here
+-- INSERT INTO "Volumes" ("Id", "NovelId", "CreatedTime", "LastUpdatedTime") VALUES (...) ON CONFLICT ("Id") DO NOTHING;

FictionArchive.Service.UserNovelDataService/Scripts/08_insert_chapters_to_usernoveldataservice.sql

@@ -0,0 +1,34 @@
+-- Insert Chapters into UserNovelDataService database
+-- Run this against: UserNovelDataService PostgreSQL database
+--
+-- PREREQUISITE:
+-- 1. Ensure the Chapters table exists (run EF migrations first if needed)
+-- 2. Volumes must be inserted first (FK constraint)
+-- 3. Extract chapters from NovelService using 04_extract_chapters_from_novelservice.sql
+
+-- Option 1: If you have a CSV file from export
+-- \copy "Chapters" ("Id", "VolumeId", "CreatedTime", "LastUpdatedTime") FROM '/tmp/chapters_export.csv' WITH CSV HEADER;
+
+-- Option 2: Direct cross-database insert using dblink
+-- First, install dblink extension if not already done:
+-- CREATE EXTENSION IF NOT EXISTS dblink;
+
+-- Example using dblink (adjust connection string):
+/*
+INSERT INTO "Chapters" ("Id", "VolumeId", "CreatedTime", "LastUpdatedTime")
+SELECT
+    "Id"::bigint,
+    "VolumeId"::bigint,
+    "CreatedTime"::timestamp with time zone,
+    "LastUpdatedTime"::timestamp with time zone
+FROM dblink(
+    'host=localhost port=5432 dbname=novelservice user=postgres password=yourpassword',
+    'SELECT "Id", "VolumeId", "CreatedTime", "LastUpdatedTime" FROM "Chapter"'
+) AS t("Id" bigint, "VolumeId" bigint, "CreatedTime" timestamp with time zone, "LastUpdatedTime" timestamp with time zone)
+ON CONFLICT ("Id") DO UPDATE SET
+    "VolumeId" = EXCLUDED."VolumeId",
+    "LastUpdatedTime" = EXCLUDED."LastUpdatedTime";
+*/
+
+-- Option 3: Paste generated INSERT statements from extraction script here
+-- INSERT INTO "Chapters" ("Id", "VolumeId", "CreatedTime", "LastUpdatedTime") VALUES (...) ON CONFLICT ("Id") DO NOTHING;

FictionArchive.Service.UserNovelDataService/Services/EventHandlers/ChapterCreatedEventHandler.cs

@@ -0,0 +1,53 @@
+using FictionArchive.Service.Shared.Services.EventBus;
+using FictionArchive.Service.UserNovelDataService.Models.Database;
+using FictionArchive.Service.UserNovelDataService.Models.IntegrationEvents;
+using Microsoft.EntityFrameworkCore;
+
+namespace FictionArchive.Service.UserNovelDataService.Services.EventHandlers;
+
+public class ChapterCreatedEventHandler : IIntegrationEventHandler<ChapterCreatedEvent>
+{
+    private readonly UserNovelDataServiceDbContext _dbContext;
+    private readonly ILogger<ChapterCreatedEventHandler> _logger;
+
+    public ChapterCreatedEventHandler(
+        UserNovelDataServiceDbContext dbContext,
+        ILogger<ChapterCreatedEventHandler> logger)
+    {
+        _dbContext = dbContext;
+        _logger = logger;
+    }
+
+    public async Task Handle(ChapterCreatedEvent @event)
+    {
+        // Ensure novel exists
+        var novelExists = await _dbContext.Novels.AnyAsync(n => n.Id == @event.NovelId);
+        if (!novelExists)
+        {
+            var novel = new Novel { Id = @event.NovelId };
+            _dbContext.Novels.Add(novel);
+        }
+
+        // Ensure volume exists
+        var volumeExists = await _dbContext.Volumes.AnyAsync(v => v.Id == @event.VolumeId);
+        if (!volumeExists)
+        {
+            var volume = new Volume { Id = @event.VolumeId };
+            _dbContext.Volumes.Add(volume);
+        }
+
+        // Create chapter if not exists
+        var chapterExists = await _dbContext.Chapters.AnyAsync(c => c.Id == @event.ChapterId);
+        if (chapterExists)
+        {
+            _logger.LogDebug("Chapter {ChapterId} already exists, skipping", @event.ChapterId);
+            return;
+        }
+
+        var chapter = new Chapter { Id = @event.ChapterId };
+        _dbContext.Chapters.Add(chapter);
+        await _dbContext.SaveChangesAsync();
+
+        _logger.LogInformation("Created chapter stub for {ChapterId} in novel {NovelId}", @event.ChapterId, @event.NovelId);
+    }
+}

FictionArchive.Service.UserNovelDataService/Services/EventHandlers/NovelCreatedEventHandler.cs

@@ -0,0 +1,36 @@
+using FictionArchive.Service.Shared.Services.EventBus;
+using FictionArchive.Service.UserNovelDataService.Models.Database;
+using FictionArchive.Service.UserNovelDataService.Models.IntegrationEvents;
+using Microsoft.EntityFrameworkCore;
+
+namespace FictionArchive.Service.UserNovelDataService.Services.EventHandlers;
+
+public class NovelCreatedEventHandler : IIntegrationEventHandler<NovelCreatedEvent>
+{
+    private readonly UserNovelDataServiceDbContext _dbContext;
+    private readonly ILogger<NovelCreatedEventHandler> _logger;
+
+    public NovelCreatedEventHandler(
+        UserNovelDataServiceDbContext dbContext,
+        ILogger<NovelCreatedEventHandler> logger)
+    {
+        _dbContext = dbContext;
+        _logger = logger;
+    }
+
+    public async Task Handle(NovelCreatedEvent @event)
+    {
+        var exists = await _dbContext.Novels.AnyAsync(n => n.Id == @event.NovelId);
+        if (exists)
+        {
+            _logger.LogDebug("Novel {NovelId} already exists, skipping", @event.NovelId);
+            return;
+        }
+
+        var novel = new Novel { Id = @event.NovelId };
+        _dbContext.Novels.Add(novel);
+        await _dbContext.SaveChangesAsync();
+
+        _logger.LogInformation("Created novel stub for {NovelId}", @event.NovelId);
+    }
+}

FictionArchive.Service.UserNovelDataService/Services/EventHandlers/UserInvitedEventHandler.cs

@@ -0,0 +1,40 @@
+using FictionArchive.Service.Shared.Services.EventBus;
+using FictionArchive.Service.UserNovelDataService.Models.Database;
+using FictionArchive.Service.UserNovelDataService.Models.IntegrationEvents;
+using Microsoft.EntityFrameworkCore;
+
+namespace FictionArchive.Service.UserNovelDataService.Services.EventHandlers;
+
+public class UserInvitedEventHandler : IIntegrationEventHandler<UserInvitedEvent>
+{
+    private readonly UserNovelDataServiceDbContext _dbContext;
+    private readonly ILogger<UserInvitedEventHandler> _logger;
+
+    public UserInvitedEventHandler(
+        UserNovelDataServiceDbContext dbContext,
+        ILogger<UserInvitedEventHandler> logger)
+    {
+        _dbContext = dbContext;
+        _logger = logger;
+    }
+
+    public async Task Handle(UserInvitedEvent @event)
+    {
+        var exists = await _dbContext.Users.AnyAsync(u => u.Id == @event.InvitedUserId);
+        if (exists)
+        {
+            _logger.LogDebug("User {UserId} already exists, skipping", @event.InvitedUserId);
+            return;
+        }
+
+        var user = new User
+        {
+            Id = @event.InvitedUserId,
+            OAuthProviderId = @event.InvitedOAuthProviderId
+        };
+        _dbContext.Users.Add(user);
+        await _dbContext.SaveChangesAsync();
+
+        _logger.LogInformation("Created user stub for {UserId}", @event.InvitedUserId);
+    }
+}

FictionArchive.Service.UserNovelDataService/Services/UserNovelDataServiceDbContext.cs

@@ -8,6 +8,9 @@ public class UserNovelDataServiceDbContext : FictionArchiveDbContext
 {
     public DbSet<User> Users { get; set; }
     public DbSet<Bookmark> Bookmarks { get; set; }
+    public DbSet<Novel> Novels { get; set; }
+    public DbSet<Volume> Volumes { get; set; }
+    public DbSet<Chapter> Chapters { get; set; }
 
     public UserNovelDataServiceDbContext(DbContextOptions options, ILogger<UserNovelDataServiceDbContext> logger) : base(options, logger)
     {