Add KurrentDB integration and mark EventStore as obsolete (#895)

* Initial plan

* Add KurrentDB integration and mark EventStore as obsolete

Co-authored-by: aaronpowell <434140+aaronpowell@users.noreply.github.com>

* Add tests for KurrentDB integration

Co-authored-by: aaronpowell <434140+aaronpowell@users.noreply.github.com>

* Add KurrentDB examples and update test workflow

Co-authored-by: aaronpowell <434140+aaronpowell@users.noreply.github.com>

* Revert API file changes and remove manually created KurrentDB API files

Co-authored-by: aaronpowell <434140+aaronpowell@users.noreply.github.com>

* Update README to use correct KurrentDB type names and GitHub links

Co-authored-by: aaronpowell <434140+aaronpowell@users.noreply.github.com>

* Remove EventStore test projects from repository and CI workflow

Co-authored-by: aaronpowell <434140+aaronpowell@users.noreply.github.com>

* Update solution file to include KurrentDB projects and remove EventStore test projects

Co-authored-by: aaronpowell <434140+aaronpowell@users.noreply.github.com>

* Removing test from the test list

* Registering the right client

* Fixing a bunch of places that were still using EventStoreClient

* Fix KurrentDB tracing

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: aaronpowell <434140+aaronpowell@users.noreply.github.com>
Co-authored-by: Aaron Powell <me@aaron-powell.com>
Co-authored-by: Fredi Machado <fredisoft@gmail.com>

Author: 3 people

.github/workflows/tests.yaml

@@ -28,13 +28,13 @@ jobs:
             Hosting.Dapr.Tests,
             Hosting.DbGate.Tests,
             Hosting.Deno.Tests,
-            Hosting.EventStore.Tests,
             Hosting.Flagd.Tests,
             Hosting.GoFeatureFlag.Tests,
             Hosting.Golang.Tests,
             Hosting.Java.Tests,
             Hosting.Keycloak.Extensions.Tests,
             Hosting.k6.Tests,
+            Hosting.KurrentDB.Tests,
             Hosting.LavinMQ.Tests,
             Hosting.MailPit.Tests,
             Hosting.McpInspector.Tests,
@@ -60,8 +60,8 @@ jobs:
             Hosting.SurrealDb.Tests,
 
             # Client integration tests
-            EventStore.Tests,
             GoFeatureFlag.Tests,
+            KurrentDB.Tests,
             MassTransit.RabbitMQ.Tests,
             Meilisearch.Tests,
             Microsoft.Data.Sqlite.Tests,

CommunityToolkit.Aspire.slnx

@@ -35,6 +35,11 @@
     <Project Path="examples/eventstore/CommunityToolkit.Aspire.Hosting.EventStore.AppHost/CommunityToolkit.Aspire.Hosting.EventStore.AppHost.csproj" />
     <Project Path="examples/eventstore/CommunityToolkit.Aspire.Hosting.EventStore.ServiceDefaults/CommunityToolkit.Aspire.Hosting.EventStore.ServiceDefaults.csproj" />
   </Folder>
+  <Folder Name="/examples/kurrentdb/">
+    <Project Path="examples/kurrentdb/CommunityToolkit.Aspire.Hosting.KurrentDB.ApiService/CommunityToolkit.Aspire.Hosting.KurrentDB.ApiService.csproj" />
+    <Project Path="examples/kurrentdb/CommunityToolkit.Aspire.Hosting.KurrentDB.AppHost/CommunityToolkit.Aspire.Hosting.KurrentDB.AppHost.csproj" />
+    <Project Path="examples/kurrentdb/CommunityToolkit.Aspire.Hosting.KurrentDB.ServiceDefaults/CommunityToolkit.Aspire.Hosting.KurrentDB.ServiceDefaults.csproj" />
+  </Folder>
   <Folder Name="/examples/flagd/">
     <Project Path="examples/flagd/CommunityToolkit.Aspire.Hosting.Flagd.AppHost/CommunityToolkit.Aspire.Hosting.Flagd.AppHost.csproj" />
   </Folder>
@@ -180,6 +185,7 @@
     <Project Path="src/CommunityToolkit.Aspire.Hosting.Golang/CommunityToolkit.Aspire.Hosting.Golang.csproj" />
     <Project Path="src/CommunityToolkit.Aspire.Hosting.Java/CommunityToolkit.Aspire.Hosting.Java.csproj" />
     <Project Path="src/CommunityToolkit.Aspire.Hosting.k6/CommunityToolkit.Aspire.Hosting.k6.csproj" />
+    <Project Path="src/CommunityToolkit.Aspire.Hosting.KurrentDB/CommunityToolkit.Aspire.Hosting.KurrentDB.csproj" />
     <Project Path="src/CommunityToolkit.Aspire.Hosting.LavinMQ/CommunityToolkit.Aspire.Hosting.LavinMQ.csproj" />
     <Project Path="src/CommunityToolkit.Aspire.Hosting.MailPit/CommunityToolkit.Aspire.Hosting.MailPit.csproj" />
     <Project Path="src/CommunityToolkit.Aspire.Hosting.McpInspector/CommunityToolkit.Aspire.Hosting.McpInspector.csproj" />
@@ -203,6 +209,7 @@
     <Project Path="src/CommunityToolkit.Aspire.Hosting.Sqlite/CommunityToolkit.Aspire.Hosting.Sqlite.csproj" />
     <Project Path="src/CommunityToolkit.Aspire.Hosting.SqlServer.Extensions/CommunityToolkit.Aspire.Hosting.SqlServer.Extensions.csproj" />
     <Project Path="src/CommunityToolkit.Aspire.Hosting.SurrealDb/CommunityToolkit.Aspire.Hosting.SurrealDb.csproj" />
+    <Project Path="src/CommunityToolkit.Aspire.KurrentDB/CommunityToolkit.Aspire.KurrentDB.csproj" />
     <Project Path="src/CommunityToolkit.Aspire.MassTransit.RabbitMQ/CommunityToolkit.Aspire.MassTransit.RabbitMQ.csproj" />
     <Project Path="src/CommunityToolkit.Aspire.Meilisearch/CommunityToolkit.Aspire.Meilisearch.csproj" />
     <Project Path="src/CommunityToolkit.Aspire.Microsoft.Data.Sqlite/CommunityToolkit.Aspire.Microsoft.Data.Sqlite.csproj" />
@@ -219,20 +226,19 @@
     <Project Path="src/CommunityToolkit.Aspire.Hosting.Dapr/CommunityToolkit.Aspire.Hosting.Dapr.csproj" />
   </Folder>
   <Folder Name="/tests/">
-    <Project Path="tests/CommunityToolkit.Aspire.EventStore.Tests/CommunityToolkit.Aspire.EventStore.Tests.csproj" />
     <Project Path="tests/CommunityToolkit.Aspire.GoFeatureFlag.Tests/CommunityToolkit.Aspire.GoFeatureFlag.Tests.csproj" />
     <Project Path="tests/CommunityToolkit.Aspire.Hosting.ActiveMQ.Tests/CommunityToolkit.Aspire.Hosting.ActiveMQ.Tests.csproj" />
     <Project Path="tests/CommunityToolkit.Aspire.Hosting.Adminer.Tests/CommunityToolkit.Aspire.Hosting.Adminer.Tests.csproj" />
     <Project Path="tests/CommunityToolkit.Aspire.Hosting.Azure.DataApiBuilder.Tests/CommunityToolkit.Aspire.Hosting.Azure.DataApiBuilder.Tests.csproj" />
     <Project Path="tests/CommunityToolkit.Aspire.Hosting.Bun.Tests/CommunityToolkit.Aspire.Hosting.Bun.Tests.csproj" />
     <Project Path="tests/CommunityToolkit.Aspire.Hosting.DbGate.Tests/CommunityToolkit.Aspire.Hosting.DbGate.Tests.csproj" />
     <Project Path="tests/CommunityToolkit.Aspire.Hosting.Deno.Tests/CommunityToolkit.Aspire.Hosting.Deno.Tests.csproj" />
-    <Project Path="tests/CommunityToolkit.Aspire.Hosting.EventStore.Tests/CommunityToolkit.Aspire.Hosting.EventStore.Tests.csproj" />
     <Project Path="tests/CommunityToolkit.Aspire.Hosting.Flagd.Tests/CommunityToolkit.Aspire.Hosting.Flagd.Tests.csproj" />
     <Project Path="tests/CommunityToolkit.Aspire.Hosting.GoFeatureFlag.Tests/CommunityToolkit.Aspire.Hosting.GoFeatureFlag.Tests.csproj" />
     <Project Path="tests/CommunityToolkit.Aspire.Hosting.Golang.Tests/CommunityToolkit.Aspire.Hosting.Golang.Tests.csproj" />
     <Project Path="tests/CommunityToolkit.Aspire.Hosting.Java.Tests/CommunityToolkit.Aspire.Hosting.Java.Tests.csproj" />
     <Project Path="tests/CommunityToolkit.Aspire.Hosting.k6.Tests/CommunityToolkit.Aspire.Hosting.k6.Tests.csproj" />
+    <Project Path="tests/CommunityToolkit.Aspire.Hosting.KurrentDB.Tests/CommunityToolkit.Aspire.Hosting.KurrentDB.Tests.csproj" />
     <Project Path="tests/CommunityToolkit.Aspire.Hosting.LavinMQ.Tests/CommunityToolkit.Aspire.Hosting.LavinMQ.Tests.csproj" />
     <Project Path="tests/CommunityToolkit.Aspire.Hosting.MailPit.Tests/CommunityToolkit.Aspire.Hosting.MailPit.Tests.csproj" />
     <Project Path="tests/CommunityToolkit.Aspire.Hosting.McpInspector.Tests/CommunityToolkit.Aspire.Hosting.McpInspector.Tests.csproj" />
@@ -256,6 +262,7 @@
     <Project Path="tests/CommunityToolkit.Aspire.Hosting.Sqlite.Tests/CommunityToolkit.Aspire.Hosting.Sqlite.Tests.csproj" />
     <Project Path="tests/CommunityToolkit.Aspire.Hosting.SqlServer.Extensions.Tests/CommunityToolkit.Aspire.Hosting.SqlServer.Extensions.Tests.csproj" />
     <Project Path="tests/CommunityToolkit.Aspire.Hosting.SurrealDb.Tests/CommunityToolkit.Aspire.Hosting.SurrealDb.Tests.csproj" />
+    <Project Path="tests/CommunityToolkit.Aspire.KurrentDB.Tests/CommunityToolkit.Aspire.KurrentDB.Tests.csproj" />
     <Project Path="tests/CommunityToolkit.Aspire.Hosting.Keycloak.Extensions.Tests/CommunityToolkit.Aspire.Hosting.Keycloak.Extensions.Tests.csproj" Type="C#" />
     <Project Path="tests/CommunityToolkit.Aspire.MassTransit.RabbitMQ.Tests/CommunityToolkit.Aspire.MassTransit.RabbitMQ.Tests.csproj" />
     <Project Path="tests/CommunityToolkit.Aspire.Meilisearch.Tests/CommunityToolkit.Aspire.Meilisearch.Tests.csproj" />

Directory.Packages.props

@@ -19,6 +19,7 @@
     <PackageVersion Include="Aspire.Hosting.MongoDB" Version="$(AspireVersion)" />
     <PackageVersion Include="Aspire.Hosting.MySql" Version="$(AspireVersion)" />
     <PackageVersion Include="Aspire.Hosting.SqlServer" Version="$(AspireVersion)" />
+    <PackageVersion Include="KurrentDB.Client" Version="1.0.0" />
   </ItemGroup>
   <ItemGroup Label="Core Packages">
     <!-- AspNetCore packages -->

examples/kurrentdb/CommunityToolkit.Aspire.Hosting.KurrentDB.ApiService/Account.cs

@@ -0,0 +1,105 @@
+using System.Text.Json.Serialization;
+
+namespace CommunityToolkit.Aspire.Hosting.KurrentDB.ApiService;
+
+public class Account
+{
+    public Guid Id { get; private set; }
+    public string? Name { get; private set; }
+    public decimal Balance { get; private set; }
+
+    [JsonIgnore]
+    public int Version { get; private set; } = -1;
+
+    [NonSerialized]
+    private readonly Queue<object> uncommittedEvents = new();
+
+    public static Account Create(Guid id, string name)
+        => new(id, name);
+
+    public void Deposit(decimal amount)
+    {
+        ArgumentOutOfRangeException.ThrowIfLessThanOrEqual(amount, 0, nameof(amount));
+
+        var @event = new AccountFundsDeposited(Id, amount);
+
+        uncommittedEvents.Enqueue(@event);
+        Apply(@event);
+    }
+
+    public void Withdraw(decimal amount)
+    {
+        ArgumentOutOfRangeException.ThrowIfLessThanOrEqual(amount, 0, nameof(amount));
+        ArgumentOutOfRangeException.ThrowIfGreaterThan(amount, Balance, nameof(amount));
+
+        var @event = new AccountFundsWithdrew(Id, amount);
+
+        uncommittedEvents.Enqueue(@event);
+        Apply(@event);
+    }
+
+    public void When(object @event)
+    {
+        switch (@event)
+        {
+            case AccountCreated accountCreated:
+                Apply(accountCreated);
+                break;
+            case AccountFundsDeposited accountFundsDeposited:
+                Apply(accountFundsDeposited);
+                break;
+            case AccountFundsWithdrew accountFundsWithdrew:
+                Apply(accountFundsWithdrew);
+                break;
+        }
+    }
+
+    public object[] DequeueUncommittedEvents()
+    {
+        var dequeuedEvents = uncommittedEvents.ToArray();
+
+        uncommittedEvents.Clear();
+
+        return dequeuedEvents;
+    }
+
+    private Account()
+    {
+    }
+
+    private Account(Guid id, string name)
+    {
+        if (id == Guid.Empty)
+        {
+            throw new ArgumentException("Id cannot be empty.", nameof(id));
+        }
+        ArgumentException.ThrowIfNullOrWhiteSpace(name, nameof(name));
+
+        var @event = new AccountCreated(id, name);
+
+        uncommittedEvents.Enqueue(@event);
+        Apply(@event);
+    }
+
+    private void Apply(AccountCreated @event)
+    {
+        Version++;
+
+        Id = @event.Id;
+        Name = @event.Name;
+    }
+
+    private void Apply(AccountFundsDeposited @event)
+    {
+        Version++;
+
+        Balance += @event.Amount;
+    }
+
+    private void Apply(AccountFundsWithdrew @event)
+    {
+        Version++;
+
+        Balance -= @event.Amount;
+    }
+}

examples/kurrentdb/CommunityToolkit.Aspire.Hosting.KurrentDB.ApiService/AccountEvents.cs

@@ -0,0 +1,7 @@
+namespace CommunityToolkit.Aspire.Hosting.KurrentDB.ApiService;
+
+public record AccountCreated(Guid Id, string Name);
+
+public record AccountFundsDeposited(Guid Id, decimal Amount);
+
+public record AccountFundsWithdrew(Guid Id, decimal Amount);

examples/kurrentdb/CommunityToolkit.Aspire.Hosting.KurrentDB.ApiService/CommunityToolkit.Aspire.Hosting.KurrentDB.ApiService.csproj

@@ -0,0 +1,18 @@
+<Project Sdk="Microsoft.NET.Sdk.Web">
+
+  <PropertyGroup>
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.AspNetCore.OpenApi" />
+    <PackageReference Include="Swashbuckle.AspNetCore" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\..\..\src\CommunityToolkit.Aspire.KurrentDB\CommunityToolkit.Aspire.KurrentDB.csproj" />
+    <ProjectReference Include="..\CommunityToolkit.Aspire.Hosting.KurrentDB.ServiceDefaults\CommunityToolkit.Aspire.Hosting.KurrentDB.ServiceDefaults.csproj" />
+  </ItemGroup>
+
+</Project>

examples/kurrentdb/CommunityToolkit.Aspire.Hosting.KurrentDB.ApiService/KurrentDBExtensions.cs

@@ -0,0 +1,76 @@
+using System.Text.Json;
+using System.Text;
+using KurrentDB.Client;
+
+namespace CommunityToolkit.Aspire.Hosting.KurrentDB.ApiService;
+
+public static class KurrentDBExtensions
+{
+    public static async Task<Account?> GetAccount(this KurrentDBClient eventStore, Guid id, CancellationToken cancellationToken)
+    {
+        var readResult = eventStore.ReadStreamAsync(
+            Direction.Forwards,
+            $"account-{id:N}",
+            StreamPosition.Start,
+            cancellationToken: cancellationToken
+        );
+
+        var readState = await readResult.ReadState;
+        if (readState == ReadState.StreamNotFound)
+        {
+            return null;
+        }
+
+        var account = (Account)Activator.CreateInstance(typeof(Account), true)!;
+
+        await foreach (var resolvedEvent in readResult)
+        {
+            var @event = resolvedEvent.Deserialize();
+
+            account.When(@event!);
+        }
+
+        return account;
+    }
+
+    public static async Task AppendAccountEvents(this KurrentDBClient eventStore, Account account, CancellationToken cancellationToken)
+    {
+        var events = account.DequeueUncommittedEvents();
+
+        var eventsToAppend = events
+            .Select(@event => @event.Serialize()).ToArray();
+
+        var expectedVersion = account.Version - events.Length;
+        await eventStore.AppendToStreamAsync(
+            $"account-{account.Id:N}",
+            expectedVersion == 0 ? StreamState.NoStream : StreamState.StreamRevision((ulong)expectedVersion),
+            eventsToAppend,
+            cancellationToken: cancellationToken
+        );
+    }
+
+    private static object? Deserialize(this ResolvedEvent resolvedEvent)
+    {
+        var eventClrTypeName = JsonDocument.Parse(resolvedEvent.Event.Metadata)
+            .RootElement
+            .GetProperty("EventClrTypeName")
+            .GetString();
+
+        return JsonSerializer.Deserialize(
+            Encoding.UTF8.GetString(resolvedEvent.Event.Data.Span),
+            Type.GetType(eventClrTypeName!)!);
+    }
+
+    private static EventData Serialize(this object @event)
+    {
+        return new EventData(
+            Uuid.NewUuid(),
+            @event.GetType().Name,
+            data: Encoding.UTF8.GetBytes(JsonSerializer.Serialize(@event)),
+            metadata: Encoding.UTF8.GetBytes(JsonSerializer.Serialize(new Dictionary<string, string>
+                {
+                    { "EventClrTypeName", @event.GetType().AssemblyQualifiedName! }
+                }))
+        );
+    }
+}

examples/kurrentdb/CommunityToolkit.Aspire.Hosting.KurrentDB.ApiService/Program.cs

@@ -0,0 +1,81 @@
+using CommunityToolkit.Aspire.Hosting.KurrentDB.ApiService;
+using KurrentDB.Client;
+
+var builder = WebApplication.CreateBuilder(args);
+
+builder.AddServiceDefaults();
+
+builder.AddKurrentDBClient("kurrentdb");
+
+// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
+builder.Services.AddEndpointsApiExplorer();
+builder.Services.AddSwaggerGen();
+
+var app = builder.Build();
+
+app.UseHttpsRedirection();
+
+app.MapDefaultEndpoints();
+
+if (app.Environment.IsDevelopment())
+{
+    app.UseSwagger();
+    app.UseSwaggerUI();
+}
+
+app.MapPost("/account/create", async (KurrentDBClient eventStore, CancellationToken cancellationToken) =>
+{
+    var account = Account.Create(Guid.NewGuid(), "John Doe");
+
+    account.Deposit(100);
+
+    await eventStore.AppendAccountEvents(account, cancellationToken);
+
+    return Results.Created($"/account/{account.Id}", account);
+});
+
+app.MapGet("/account/{id:guid}", async (Guid id, KurrentDBClient eventStore, CancellationToken cancellationToken) =>
+{
+    var account = await eventStore.GetAccount(id, cancellationToken);
+    if (account is null)
+    {
+        return Results.NotFound();
+    }
+
+    return TypedResults.Ok(account);
+});
+
+app.MapPost("/account/{id:guid}/deposit", async (Guid id, DepositRequest request, KurrentDBClient eventStore, CancellationToken cancellationToken) =>
+{
+    var account = await eventStore.GetAccount(id, cancellationToken);
+    if (account is null)
+    {
+        return Results.NotFound();
+    }
+
+    account.Deposit(request.Amount);
+
+    await eventStore.AppendAccountEvents(account, cancellationToken);
+
+    return Results.Ok();
+});
+
+app.MapPost("/account/{id:guid}/withdraw", async (Guid id, WithdrawRequest request, KurrentDBClient eventStore, CancellationToken cancellationToken) =>
+{
+    var account = await eventStore.GetAccount(id, cancellationToken);
+    if (account is null)
+    {
+        return Results.NotFound();
+    }
+
+    account.Withdraw(request.Amount);
+
+    await eventStore.AppendAccountEvents(account, cancellationToken);
+
+    return Results.Ok();
+});
+
+app.Run();
+
+public record DepositRequest(decimal Amount);
+public record WithdrawRequest(decimal Amount);