services/domain/Big.Tests/BeoordeelRegistratieTests.cs

@@ -19,7 +19,7 @@ public class BeoordeelRegistratieTests
     }
 
     private static FakeUserTaskClient TaskFor(Registration registration) =>
-        new([new BeoordelingTask("task-1", registration.Id)]);
+        new([new BeoordelingTask("task-1", "exec-1", registration.Id)]);
 
     [Fact]
     public async Task Goedkeuren_sets_the_zaak_status_via_the_acl_and_marks_the_registration_ingeschreven()

services/domain/Big.Tests/Fakes.cs

@@ -47,6 +47,7 @@ internal sealed class FakeUserTaskClient(IReadOnlyList<BeoordelingTask> open) :
 {
     public (string TaskId, string Behandelaar)? Claimed { get; private set; }
     public (string TaskId, BeoordelingsBesluit Besluit)? Completed { get; private set; }
+    public string? WithdrawnExecutionId { get; private set; }
 
     public Task<IReadOnlyList<BeoordelingTask>> GetOpenBeoordelingenAsync(CancellationToken ct = default)
         => Task.FromResult(open);
@@ -62,6 +63,12 @@ internal sealed class FakeUserTaskClient(IReadOnlyList<BeoordelingTask> open) :
         Completed = (taskId, besluit);
         return Task.CompletedTask;
     }
+
+    public Task WithdrawBeoordelingAsync(string executionId, CancellationToken ct = default)
+    {
+        WithdrawnExecutionId = executionId;
+        return Task.CompletedTask;
+    }
 }
 
 /// <summary>A fake ACL client that records the bsn it was asked to open a zaak for and returns a

services/domain/Big.Tests/FlowableWorkflowClientTests.cs

@@ -158,13 +158,14 @@ public class FlowableWorkflowClientTests
         var capture = new RequestCapture();
         var client = Client(capture.Responds(HttpStatusCode.OK,
             $$"""
-            {"data":[{"id":"task-1","variables":[{"name":"registrationId","type":"string","value":"{{rid}}"}]}],"total":1}
+            {"data":[{"id":"task-1","executionId":"exec-1","variables":[{"name":"registrationId","type":"string","value":"{{rid}}"}]}],"total":1}
             """));
 
         var tasks = await client.GetOpenBeoordelingenAsync();
 
         var task = Assert.Single(tasks);
         Assert.Equal("task-1", task.TaskId);
+        Assert.Equal("exec-1", task.ExecutionId);
         Assert.Equal(rid, task.RegistrationId);
         Assert.Equal(HttpMethod.Post, capture.Seen!.Method);
         Assert.Equal("http://flowable/flowable-rest/service/query/tasks",
@@ -242,6 +243,32 @@ public class FlowableWorkflowClientTests
         Assert.Contains($"\"value\":\"{expected}\"", capture.Body);
     }
 
+    [Fact]
+    public async Task Withdraw_beoordeling_delivers_the_message_to_the_task_execution()
+    {
+        var capture = new RequestCapture();
+        var client = Client(capture.Responds(HttpStatusCode.OK));
+
+        await client.WithdrawBeoordelingAsync("exec-1");
+
+        // A PUT messageEventReceived on the execution trips the Beoordelen boundary event (ADR-0014).
+        Assert.Equal(HttpMethod.Put, capture.Seen!.Method);
+        Assert.Equal("http://flowable/flowable-rest/service/runtime/executions/exec-1",
+            capture.Seen.RequestUri!.ToString());
+        Assert.Equal("rest-admin:test", DecodeBasic(capture.Seen));
+        Assert.Contains("\"action\":\"messageEventReceived\"", capture.Body);
+        Assert.Contains("\"messageName\":\"RegistratieIngetrokken\"", capture.Body);
+    }
+
+    [Fact]
+    public async Task Withdraw_beoordeling_throws_when_flowable_rejects_the_request()
+    {
+        var capture = new RequestCapture();
+        var client = Client(capture.Responds(HttpStatusCode.InternalServerError));
+
+        await Assert.ThrowsAsync<HttpRequestException>(() => client.WithdrawBeoordelingAsync("exec-1"));
+    }
+
     [Fact]
     public async Task Complete_beoordeling_throws_when_flowable_rejects_the_request()
     {

services/domain/Big.Tests/WerkbakTests.cs

@@ -18,7 +18,7 @@ public class WerkbakTests
         registration.AttachZaak(FakeAclClient.DefaultZaakUrl);
         registration.TakeIntoBehandeling();
         store.Seed(registration);
-        var tasks = new FakeUserTaskClient([new BeoordelingTask("task-1", registration.Id)]);
+        var tasks = new FakeUserTaskClient([new BeoordelingTask("task-1", "exec-1",registration.Id)]);
         var werkbak = new Werkbak(tasks, store);
 
         var items = await werkbak.GetAsync();
@@ -41,7 +41,7 @@ public class WerkbakTests
     public async Task Skips_a_task_whose_registration_is_unknown()
     {
         // Defensive: the werkbak never invents an item for a task the domain has no aggregate for.
-        var tasks = new FakeUserTaskClient([new BeoordelingTask("task-1", RegistrationId.New())]);
+        var tasks = new FakeUserTaskClient([new BeoordelingTask("task-1", "exec-1",RegistrationId.New())]);
         var werkbak = new Werkbak(tasks, new FakeRegistrationStore());
 
         Assert.Empty(await werkbak.GetAsync());
@@ -56,7 +56,7 @@ public class WerkbakTests
         var registration = Registration.Submit("123456782");
         registration.Withdraw();
         store.Seed(registration);
-        var tasks = new FakeUserTaskClient([new BeoordelingTask("task-1", registration.Id)]);
+        var tasks = new FakeUserTaskClient([new BeoordelingTask("task-1", "exec-1",registration.Id)]);
         var werkbak = new Werkbak(tasks, store);
 
         Assert.Empty(await werkbak.GetAsync());

services/domain/Big.Tests/WithdrawRegistrationTests.cs

@@ -5,13 +5,15 @@ namespace Big.Tests;
 
 public class WithdrawRegistrationTests
 {
+    private static FakeUserTaskClient NoTasks() => new([]);
+
     [Fact]
     public async Task Withdrawing_marks_the_registration_ingetrokken_and_persists_it()
     {
         var store = new FakeRegistrationStore();
         var registration = Registration.Submit("123456782");
         store.Seed(registration);
-        var handler = new WithdrawRegistration(store);
+        var handler = new WithdrawRegistration(store, NoTasks());
 
         await handler.HandleAsync(new WithdrawRegistrationCommand(registration.Id));
 
@@ -20,11 +22,44 @@ public class WithdrawRegistrationTests
         Assert.Equal(1, store.SaveCount);
     }
 
+    [Fact]
+    public async Task Withdrawing_cancels_the_open_beoordelen_task_via_its_execution()
+    {
+        var store = new FakeRegistrationStore();
+        var registration = Registration.Submit("123456782");
+        store.Seed(registration);
+        var tasks = new FakeUserTaskClient([new BeoordelingTask("task-1", "exec-1", registration.Id)]);
+        var handler = new WithdrawRegistration(store, tasks);
+
+        await handler.HandleAsync(new WithdrawRegistrationCommand(registration.Id));
+
+        // The withdrawal message is delivered to the Beoordelen task's execution, tripping the
+        // boundary event that ends the process (ADR-0014).
+        Assert.Equal("exec-1", tasks.WithdrawnExecutionId);
+    }
+
+    [Fact]
+    public async Task Withdrawing_with_no_open_task_still_marks_ingetrokken()
+    {
+        // If the process has not parked at Beoordelen yet (or already ended), the withdrawal stands:
+        // the aggregate is INGETROKKEN and nothing is cancelled.
+        var store = new FakeRegistrationStore();
+        var registration = Registration.Submit("123456782");
+        store.Seed(registration);
+        var tasks = NoTasks();
+        var handler = new WithdrawRegistration(store, tasks);
+
+        await handler.HandleAsync(new WithdrawRegistrationCommand(registration.Id));
+
+        Assert.Equal(RegistrationStatus.Ingetrokken, (await store.GetAsync(registration.Id))!.Status);
+        Assert.Null(tasks.WithdrawnExecutionId);
+    }
+
     [Fact]
     public async Task Rejects_a_null_command_without_touching_the_store()
     {
         var store = new FakeRegistrationStore();
-        var handler = new WithdrawRegistration(store);
+        var handler = new WithdrawRegistration(store, NoTasks());
 
         await Assert.ThrowsAsync<ArgumentNullException>(() => handler.HandleAsync(null!));
         Assert.Equal(0, store.SaveCount);
@@ -34,7 +69,7 @@ public class WithdrawRegistrationTests
     public async Task Withdrawing_an_unknown_registration_throws()
     {
         var store = new FakeRegistrationStore();
-        var handler = new WithdrawRegistration(store);
+        var handler = new WithdrawRegistration(store, NoTasks());
 
         var ex = await Assert.ThrowsAsync<InvalidOperationException>(
             () => handler.HandleAsync(new WithdrawRegistrationCommand(RegistrationId.New())));
@@ -48,7 +83,7 @@ public class WithdrawRegistrationTests
         var store = new FakeRegistrationStore();
         var registration = Registration.Submit("123456782");
         store.Seed(registration);
-        var handler = new WithdrawRegistration(store);
+        var handler = new WithdrawRegistration(store, NoTasks());
 
         await handler.HandleAsync(new WithdrawRegistrationCommand(registration.Id));
         await handler.HandleAsync(new WithdrawRegistrationCommand(registration.Id));