feat: add Chat module with TanStack AI streaming and RAG

Dockerfile

@@ -86,6 +86,8 @@ COPY modules/Email/src/SimpleModule.Email.Contracts/*.csproj modules/Email/src/S
 COPY modules/Email/src/SimpleModule.Email/*.csproj modules/Email/src/SimpleModule.Email/
 COPY modules/RateLimiting/src/SimpleModule.RateLimiting.Contracts/*.csproj modules/RateLimiting/src/SimpleModule.RateLimiting.Contracts/
 COPY modules/RateLimiting/src/SimpleModule.RateLimiting/*.csproj modules/RateLimiting/src/SimpleModule.RateLimiting/
+COPY modules/Chat/src/SimpleModule.Chat.Contracts/*.csproj modules/Chat/src/SimpleModule.Chat.Contracts/
+COPY modules/Chat/src/SimpleModule.Chat/*.csproj modules/Chat/src/SimpleModule.Chat/
 
 RUN dotnet restore template/SimpleModule.Host/SimpleModule.Host.csproj
 
@@ -115,6 +117,7 @@ COPY modules/Users/src/SimpleModule.Users/package.json modules/Users/src/SimpleM
 COPY modules/BackgroundJobs/src/SimpleModule.BackgroundJobs/package.json modules/BackgroundJobs/src/SimpleModule.BackgroundJobs/
 COPY modules/Email/src/SimpleModule.Email/package.json modules/Email/src/SimpleModule.Email/
 COPY modules/RateLimiting/src/SimpleModule.RateLimiting/package.json modules/RateLimiting/src/SimpleModule.RateLimiting/
+COPY modules/Chat/src/SimpleModule.Chat/package.json modules/Chat/src/SimpleModule.Chat/
 COPY packages/SimpleModule.Client/package.json packages/SimpleModule.Client/
 COPY packages/SimpleModule.Theme.Default/package.json packages/SimpleModule.Theme.Default/
 COPY packages/SimpleModule.TsConfig/package.json packages/SimpleModule.TsConfig/

SimpleModule.slnx

@@ -108,6 +108,11 @@
     <Project Path="modules/Agents/src/SimpleModule.Agents.Module/SimpleModule.Agents.Module.csproj" />
     <Project Path="modules/Agents/tests/SimpleModule.Agents.Tests/SimpleModule.Agents.Tests.csproj" />
   </Folder>
+  <Folder Name="/modules/Chat/">
+    <Project Path="modules/Chat/src/SimpleModule.Chat.Contracts/SimpleModule.Chat.Contracts.csproj" />
+    <Project Path="modules/Chat/src/SimpleModule.Chat/SimpleModule.Chat.csproj" />
+    <Project Path="modules/Chat/tests/SimpleModule.Chat.Tests/SimpleModule.Chat.Tests.csproj" />
+  </Folder>
   <Folder Name="/modules/BackgroundJobs/">
     <Project Path="modules/BackgroundJobs/src/SimpleModule.BackgroundJobs.Contracts/SimpleModule.BackgroundJobs.Contracts.csproj" />
     <Project Path="modules/BackgroundJobs/src/SimpleModule.BackgroundJobs/SimpleModule.BackgroundJobs.csproj" />

framework/SimpleModule.Agents/AgentChatService.cs

@@ -131,6 +131,21 @@ CancellationToken cancellationToken
             }
         }
 
+        if (request.History is { Count: > 0 })
+        {
+            foreach (var turn in request.History)
+            {
+                if (string.IsNullOrWhiteSpace(turn.Content))
+                {
+                    continue;
+                }
+                var role = string.Equals(turn.Role, "assistant", StringComparison.OrdinalIgnoreCase)
+                    ? ChatRole.Assistant
+                    : ChatRole.User;
+                messages.Add(new ChatMessage(role, turn.Content));
+            }
+        }
+
         messages.Add(new ChatMessage(ChatRole.User, request.Message));
 
         var chatOptions = new ChatOptions

framework/SimpleModule.Agents/Dtos/AgentChatRequest.cs

@@ -3,5 +3,12 @@ namespace SimpleModule.Agents.Dtos;
 public sealed record AgentChatRequest(
     string Message,
     string? SessionId = null,
-    string? ResponseType = null
+    string? ResponseType = null,
+    IReadOnlyList<AgentHistoryMessage>? History = null
 );
+
+/// <summary>
+/// A prior turn in the conversation. Role must be "user" or "assistant".
+/// System messages are provided by the agent definition and should not appear here.
+/// </summary>
+public sealed record AgentHistoryMessage(string Role, string Content);

modules/Chat/src/SimpleModule.Chat.Contracts/ChatConstants.cs

@@ -0,0 +1,22 @@
+namespace SimpleModule.Chat.Contracts;
+
+public static class ChatConstants
+{
+    public const string ModuleName = "Chat";
+    public const string RoutePrefix = "/api/chat";
+    public const string ViewPrefix = "/chat";
+
+    public static class Routes
+    {
+        public const string ListConversations = "/conversations";
+        public const string CreateConversation = "/conversations";
+        public const string GetConversation = "/conversations/{id:guid}";
+        public const string RenameConversation = "/conversations/{id:guid}";
+        public const string DeleteConversation = "/conversations/{id:guid}";
+        public const string GetMessages = "/conversations/{id:guid}/messages";
+        public const string SendMessageStream = "/conversations/{id:guid}/stream";
+
+        public const string Browse = "/";
+        public const string Conversation = "/{id:guid}";
+    }
+}

modules/Chat/src/SimpleModule.Chat.Contracts/ChatMessage.cs

@@ -0,0 +1,29 @@
+namespace SimpleModule.Chat.Contracts;
+
+public class ChatMessage
+{
+    public ChatMessageId Id { get; set; }
+    public ConversationId ConversationId { get; set; }
+    public ChatRole Role { get; set; }
+    public string Content { get; set; } = string.Empty;
+    public DateTimeOffset CreatedAt { get; set; }
+}
+
+public enum ChatRole
+{
+    User = 0,
+    Assistant = 1,
+    System = 2,
+}
+
+public static class ChatRoleExtensions
+{
+    public static string ToWire(ChatRole role) =>
+        role switch
+        {
+            ChatRole.User => "user",
+            ChatRole.Assistant => "assistant",
+            ChatRole.System => "system",
+            _ => "user",
+        };
+}

modules/Chat/src/SimpleModule.Chat.Contracts/ChatMessageId.cs

@@ -0,0 +1,6 @@
+using Vogen;
+
+namespace SimpleModule.Chat.Contracts;
+
+[ValueObject<Guid>(conversions: Conversions.SystemTextJson | Conversions.EfCoreValueConverter)]
+public readonly partial struct ChatMessageId;

modules/Chat/src/SimpleModule.Chat.Contracts/Conversation.cs

@@ -0,0 +1,14 @@
+namespace SimpleModule.Chat.Contracts;
+
+public class Conversation
+{
+    public ConversationId Id { get; set; }
+    public string UserId { get; set; } = string.Empty;
+    public string Title { get; set; } = "New conversation";
+    public string AgentName { get; set; } = string.Empty;
+    public bool Pinned { get; set; }
+    public DateTimeOffset CreatedAt { get; set; }
+    public DateTimeOffset UpdatedAt { get; set; }
+
+    public List<ChatMessage> Messages { get; set; } = [];
+}

modules/Chat/src/SimpleModule.Chat.Contracts/ConversationId.cs

@@ -0,0 +1,6 @@
+using Vogen;
+
+namespace SimpleModule.Chat.Contracts;
+
+[ValueObject<Guid>(conversions: Conversions.SystemTextJson | Conversions.EfCoreValueConverter)]
+public readonly partial struct ConversationId;

modules/Chat/src/SimpleModule.Chat.Contracts/CreateConversationRequest.cs

@@ -0,0 +1,12 @@
+namespace SimpleModule.Chat.Contracts;
+
+public sealed class CreateConversationRequest
+{
+    public string AgentName { get; set; } = string.Empty;
+    public string? Title { get; set; }
+}
+
+public sealed class RenameConversationRequest
+{
+    public string Title { get; set; } = string.Empty;
+}

modules/Chat/src/SimpleModule.Chat.Contracts/IChatContracts.cs

@@ -0,0 +1,16 @@
+namespace SimpleModule.Chat.Contracts;
+
+public interface IChatContracts
+{
+    Task<IReadOnlyList<Conversation>> GetUserConversationsAsync(
+        string userId,
+        CancellationToken cancellationToken = default
+    );
+
+    Task<Conversation> StartConversationAsync(
+        string userId,
+        string agentName,
+        string? title,
+        CancellationToken cancellationToken = default
+    );
+}

modules/Chat/src/SimpleModule.Chat.Contracts/SimpleModule.Chat.Contracts.csproj

@@ -0,0 +1,12 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <TargetFramework>net10.0</TargetFramework>
+    <OutputType>Library</OutputType>
+    <DefineConstants>$(DefineConstants);VOGEN_NO_VALIDATION</DefineConstants>
+  </PropertyGroup>
+  <ItemGroup>
+    <PackageReference Include="Microsoft.EntityFrameworkCore" />
+    <PackageReference Include="Vogen" />
+    <ProjectReference Include="..\..\..\..\framework\SimpleModule.Core\SimpleModule.Core.csproj" />
+  </ItemGroup>
+</Project>

modules/Chat/src/SimpleModule.Chat/ChatDbContext.cs

@@ -0,0 +1,39 @@
+using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.Options;
+using SimpleModule.Chat.Contracts;
+using SimpleModule.Chat.EntityConfigurations;
+using SimpleModule.Database;
+
+namespace SimpleModule.Chat;
+
+public class ChatDbContext(
+    DbContextOptions<ChatDbContext> options,
+    IOptions<DatabaseOptions> dbOptions
+) : DbContext(options)
+{
+    public DbSet<Conversation> Conversations => Set<Conversation>();
+    public DbSet<ChatMessage> ChatMessages => Set<ChatMessage>();
+
+    protected override void OnModelCreating(ModelBuilder modelBuilder)
+    {
+        modelBuilder.ApplyConfiguration(new ConversationConfiguration());
+        modelBuilder.ApplyConfiguration(new ChatMessageConfiguration());
+        modelBuilder.ApplyModuleSchema("Chat", dbOptions.Value);
+    }
+
+    protected override void ConfigureConventions(ModelConfigurationBuilder configurationBuilder)
+    {
+        configurationBuilder
+            .Properties<ConversationId>()
+            .HaveConversion<
+                ConversationId.EfCoreValueConverter,
+                ConversationId.EfCoreValueComparer
+            >();
+        configurationBuilder
+            .Properties<ChatMessageId>()
+            .HaveConversion<
+                ChatMessageId.EfCoreValueConverter,
+                ChatMessageId.EfCoreValueComparer
+            >();
+    }
+}

modules/Chat/src/SimpleModule.Chat/ChatModule.cs

@@ -0,0 +1,44 @@
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.DependencyInjection;
+using SimpleModule.Chat.Contracts;
+using SimpleModule.Core;
+using SimpleModule.Core.Authorization;
+using SimpleModule.Core.Menu;
+using SimpleModule.Database;
+
+namespace SimpleModule.Chat;
+
+[Module(
+    ChatConstants.ModuleName,
+    RoutePrefix = ChatConstants.RoutePrefix,
+    ViewPrefix = ChatConstants.ViewPrefix
+)]
+public class ChatModule : IModule, IModuleServices, IModuleMenu
+{
+    public void ConfigureServices(IServiceCollection services, IConfiguration configuration)
+    {
+        services.AddModuleDbContext<ChatDbContext>(configuration, ChatConstants.ModuleName);
+        services.AddScoped<ChatService>();
+        services.AddScoped<IChatContracts>(sp => sp.GetRequiredService<ChatService>());
+    }
+
+    public void ConfigurePermissions(PermissionRegistryBuilder builder)
+    {
+        builder.AddPermissions<ChatPermissions>();
+    }
+
+    public void ConfigureMenu(IMenuBuilder menus)
+    {
+        menus.Add(
+            new MenuItem
+            {
+                Label = "Chat",
+                Url = "/chat",
+                Icon =
+                    """<svg class="w-4 h-4" fill="none" stroke="currentColor" stroke-width="2" viewBox="0 0 24 24"><path stroke-linecap="round" stroke-linejoin="round" d="M8 12h.01M12 12h.01M16 12h.01M21 12c0 4.418-4.03 8-9 8a9.87 9.87 0 01-4-.8L3 20l1.2-3.6A7.96 7.96 0 013 12c0-4.418 4.03-8 9-8s9 3.582 9 8z"/></svg>""",
+                Order = 40,
+                Section = MenuSection.AppSidebar,
+            }
+        );
+    }
+}

modules/Chat/src/SimpleModule.Chat/ChatPermissions.cs

@@ -0,0 +1,10 @@
+using SimpleModule.Core.Authorization;
+
+namespace SimpleModule.Chat;
+
+public sealed class ChatPermissions : IModulePermissions
+{
+    public const string View = "Chat.View";
+    public const string Create = "Chat.Create";
+    public const string ManageAll = "Chat.ManageAll";
+}