Separate GA and Pre-Release features for Nexus Messaging samples

README.md

@@ -30,9 +30,11 @@ Prerequisites:
 * [NexusCancellation](src/NexusCancellation) - Demonstrates how to cancel a running Nexus operation from a caller workflow.
 * [NexusContextPropagation](src/NexusContextPropagation) - Context propagation through Nexus services.
 * [NexusDependencyInjection](src/NexusDependencyInjection) - How to configure a Nexus service handler for dependency injection using a generic host worker.
-* [Nexus Messaging](src/NexusMessaging): Demonstrates how send signal, update and query messages through Nexus.
+* [Nexus Messaging](src/NexusMessaging): Demonstrates how to send signal, update and query messages through Nexus.
     This contains two samples, one sending messages to an existing workflow and a second that creates a workflow through Nexus
     and sends messages to it.
+* [Nexus Messaging Temporal Operation](src/NexusMessagingTemporalOperation): Demonstrates how to send signal, update and query messages through Nexus.
+  This version uses the `[TemporalOperation]` attribute to declare a Temporal-backed Nexus operation start handler directly on a method within a `[NexusServiceHandler]` class.
 * [NexusMultiArg](src/NexusMultiArg) - Nexus service implementation calling a workflow with multiple arguments.
 * [NexusSimple](src/NexusSimple) - Simple Nexus service implementation.
 * [NexusStandaloneActivity](src/NexusStandaloneActivity) - Nexus Operation backed by a Standalone Activity.

TemporalioSamples.slnx

@@ -11,7 +11,6 @@
     <Project Path="src/EagerWorkflowStart/TemporalioSamples.EagerWorkflowStart.csproj" />
     <Project Path="src/EnvConfig/TemporalioSamples.EnvConfig.csproj" />
     <Project Path="src/Mutex/TemporalioSamples.Mutex.csproj" />
-    <Project Path="src/NexusMessaging/TemporalioSamples.NexusMessaging.csproj" />
     <Project Path="src/Patching/TemporalioSamples.Patching.csproj" />
     <Project Path="src/SafeMessageHandlers/TemporalioSamples.SafeMessageHandlers.csproj" />
     <Project Path="src/Saga/TemporalioSamples.Saga.csproj" />
@@ -60,6 +59,12 @@
   <Folder Name="/src/NexusDependencyInjection/">
     <Project Path="src/NexusDependencyInjection/TemporalioSamples.NexusDependencyInjection.csproj" />
   </Folder>
+  <Folder Name="/src/NexusMessaging/">
+    <Project Path="src/NexusMessaging/TemporalioSamples.NexusMessaging.csproj" />
+  </Folder>
+  <Folder Name="/src/NexusMessagingTemporalOperation/">
+    <Project Path="src/NexusMessagingTemporalOperation/TemporalioSamples.NexusMessagingTemporalOperation.csproj" />
+  </Folder>
   <Folder Name="/src/NexusMultiArg/">
     <Project Path="src/NexusMultiArg/TemporalioSamples.NexusMultiArg.csproj" />
   </Folder>

src/NexusMessaging/CallerPattern/Handler/NexusGreetingService.cs

@@ -1,7 +1,6 @@
 namespace TemporalioSamples.NexusMessaging.CallerPattern.Handler;
 
 using NexusRpc.Handlers;
-using Temporalio.Client;
 using Temporalio.Nexus;
 using TemporalioSamples.NexusMessaging.CallerPattern;
 using TemporalioSamples.NexusMessaging.Common;
@@ -12,63 +11,55 @@ namespace TemporalioSamples.NexusMessaging.CallerPattern.Handler;
 [NexusServiceHandler(typeof(INexusGreetingService))]
 public class NexusGreetingService
 {
-#pragma warning disable VSTHRD200 // Names must match the INexusGreetingService operations, which can't take the Async suffix
+    // OperationHandler.Sync means the result is returned inline to the Nexus caller
+    // (as opposed to WorkflowRunOperationHandler, which returns an async operation token).
+    // The lambda may still be async internally.
 
     // Query: read-only, no state mutation — uses workflow query
-    [TemporalOperation]
-    public async Task<TemporalOperationResult<INexusGreetingService.GetLanguagesOutput>> GetLanguages(
-        TemporalOperationStartContext ctx,
-        ITemporalNexusClient client,
-        INexusGreetingService.GetLanguagesInput input)
-    {
-        // Access the Temporal client from the Nexus client passed to the handler
-        var handle = client.TemporalClient.GetWorkflowHandle<GreetingWorkflow>(
-            WorkflowIdForUser(input.UserId));
-        return TemporalOperationResult<INexusGreetingService.GetLanguagesOutput>.SyncResult(
-            await handle.QueryAsync(wf => wf.QueryLanguages(input.IncludeUnsupported)));
-    }
+    [NexusOperationHandler]
+    public IOperationHandler<INexusGreetingService.GetLanguagesInput, INexusGreetingService.GetLanguagesOutput> GetLanguages() =>
+        OperationHandler.Sync<INexusGreetingService.GetLanguagesInput, INexusGreetingService.GetLanguagesOutput>(
+            async (ctx, input) =>
+            {
+                // Access the Temporal client from the Nexus operation context
+                var client = NexusOperationExecutionContext.Current.TemporalClient;
+                var handle = client.GetWorkflowHandle<GreetingWorkflow>(WorkflowIdForUser(input.UserId));
+                return await handle.QueryAsync(wf => wf.QueryLanguages(input.IncludeUnsupported));
+            });
 
     // Query: read-only — returns the workflow's current language
-    [TemporalOperation]
-    public async Task<TemporalOperationResult<Language>> GetLanguage(
-        TemporalOperationStartContext ctx,
-        ITemporalNexusClient client,
-        INexusGreetingService.GetLanguageInput input)
-    {
-        var handle = client.TemporalClient.GetWorkflowHandle<GreetingWorkflow>(
-            WorkflowIdForUser(input.UserId));
-        return TemporalOperationResult<Language>.SyncResult(
-            await handle.QueryAsync(wf => wf.QueryLanguage()));
-    }
+    [NexusOperationHandler]
+    public IOperationHandler<INexusGreetingService.GetLanguageInput, Language> GetLanguage() =>
+        OperationHandler.Sync<INexusGreetingService.GetLanguageInput, Language>(
+            async (ctx, input) =>
+            {
+                var client = NexusOperationExecutionContext.Current.TemporalClient;
+                var handle = client.GetWorkflowHandle<GreetingWorkflow>(WorkflowIdForUser(input.UserId));
+                return await handle.QueryAsync(wf => wf.QueryLanguage());
+            });
 
     // Update: mutates state and returns the previous value — uses workflow update
-    [TemporalOperation]
-    public Task<TemporalOperationResult<Language>> SetLanguage(
-        TemporalOperationStartContext ctx,
-        ITemporalNexusClient client,
-        INexusGreetingService.SetLanguageInput input) =>
-        client.StartWorkflowUpdateAsync<GreetingWorkflow, Language>(
-            WorkflowIdForUser(input.UserId),
-            wf => wf.SetLanguageAsync(input.Language),
-            // An Update-backed Operation must wait for the Accepted stage. Any other stage is
-            // rejected with "nexus op workflow updates only support WorkflowUpdateStageAccepted
-            // for async updates".
-            new(WorkflowUpdateStage.Accepted));
+    [NexusOperationHandler]
+    public IOperationHandler<INexusGreetingService.SetLanguageInput, Language> SetLanguage() =>
+        OperationHandler.Sync<INexusGreetingService.SetLanguageInput, Language>(
+            async (ctx, input) =>
+            {
+                var client = NexusOperationExecutionContext.Current.TemporalClient;
+                var handle = client.GetWorkflowHandle<GreetingWorkflow>(WorkflowIdForUser(input.UserId));
+                return await handle.ExecuteUpdateAsync(wf => wf.SetLanguageAsync(input.Language));
+            });
 
     // Signal: fire-and-forget, no return value needed — uses workflow signal
-    [TemporalOperation]
-    public async Task<TemporalOperationResult<NoValue>> Approve(
-        TemporalOperationStartContext ctx,
-        ITemporalNexusClient client,
-        INexusGreetingService.ApproveInput input)
-    {
-        var handle = client.TemporalClient.GetWorkflowHandle<GreetingWorkflow>(
-            WorkflowIdForUser(input.UserId));
-        await handle.SignalAsync(wf => wf.ApproveAsync(input.Name));
-        return TemporalOperationResult<NoValue>.SyncResult(default);
-    }
-
-#pragma warning restore VSTHRD200
+    [NexusOperationHandler]
+    public IOperationHandler<INexusGreetingService.ApproveInput, NoValue> Approve() =>
+        OperationHandler.Sync<INexusGreetingService.ApproveInput, NoValue>(
+            async (ctx, input) =>
+            {
+                var client = NexusOperationExecutionContext.Current.TemporalClient;
+                var handle = client.GetWorkflowHandle<GreetingWorkflow>(WorkflowIdForUser(input.UserId));
+                await handle.SignalAsync(wf => wf.ApproveAsync(input.Name));
+                return default;
+            });
 
     private static string WorkflowIdForUser(string userId) => $"GreetingWorkflow_for_{userId}";
 }

src/NexusMessaging/CallerPattern/README.md

@@ -14,24 +14,19 @@ The caller Workflow:
 
 ### Running
 
-This sample requires a Temporal dev server build that supports Workflow Update callbacks. Download
-the compatible binary from the [Temporal CLI pre-release instructions](https://docs.temporal.io/standalone-nexus-operation#temporal-cli-support).
-
-Start the Temporal dev server with the required namespaces pre-created and Workflow Update
-callbacks enabled:
+Start a Temporal server:
 
 ```bash
-./temporal server start-dev \
-  --dynamic-config-value history.enableUpdateCallbacks=true \
-  --dynamic-config-value history.enableCHASMSignalBacklinks=true \
-  --namespace nexus-messaging-handler-namespace \
-  --namespace nexus-messaging-caller-namespace
+temporal server start-dev
 ```
 
-Create the Nexus endpoint:
+Create the namespaces and Nexus endpoint:
 
 ```bash
-./temporal operator nexus endpoint create \
+temporal operator namespace create --namespace nexus-messaging-handler-namespace
+temporal operator namespace create --namespace nexus-messaging-caller-namespace
+
+temporal operator nexus endpoint create \
   --name nexus-messaging-caller-pattern-endpoint \
   --target-namespace nexus-messaging-handler-namespace \
   --target-task-queue nexus-messaging-handler-sample
@@ -54,12 +49,3 @@ In a third terminal, run the following command to start the example:
 ```bash
 dotnet run --project src/NexusMessaging -- caller-workflow
 ```
-
-Expected output:
-
-```
-Supported languages: Chinese, English
-Current language: English
-Set language from English to Chinese
-Approved workflow
-```

src/NexusMessaging/OnDemandPattern/Caller/CallerRemoteWorkflow.workflow.cs

@@ -18,17 +18,6 @@ public async Task<string[]> RunAsync()
         var userIdOne = "user-one";
         var userIdTwo = "user-two";
 
-        // Attach information before the Workflow exists. Since AttachApprovalContext is backed
-        // by Signal-with-Start on the handler, this call creates the Workflow and delivers the
-        // note to it.
-        await client.ExecuteNexusOperationAsync(
-            svc => svc.AttachApprovalContext(new INexusRemoteGreetingService.AttachApprovalContextInput(
-                "queued for localization review by the nightly batch", userIdOne)));
-        log.Add($"Attached approval context before the workflow existed: {userIdOne}");
-
-        // The Workflow for this user is already running due to AttachApprovalContext. The handler
-        // sets the conflict policy to UseExisting, so this call attaches the Operation's
-        // completion callback to the running execution.
         var handleOne = await client.StartNexusOperationAsync(
             svc => svc.RunFromRemote(new INexusRemoteGreetingService.RunFromRemoteInput(userIdOne)));
         log.Add($"Started remote workflow for user: {userIdOne}");
@@ -37,13 +26,6 @@ await client.ExecuteNexusOperationAsync(
             svc => svc.RunFromRemote(new INexusRemoteGreetingService.RunFromRemoteInput(userIdTwo)));
         log.Add($"Started remote workflow for user: {userIdTwo}");
 
-        // This user's Workflow was created by RunFromRemote just above, so here Signal-with-Start
-        // skips the start and only delivers the Signal.
-        await client.ExecuteNexusOperationAsync(
-            svc => svc.AttachApprovalContext(new INexusRemoteGreetingService.AttachApprovalContextInput(
-                "translation approved by the localization team", userIdTwo)));
-        log.Add($"Attached approval context to the running workflow: {userIdTwo}");
-
         // Interact with workflow one: get languages, set language, approve
         var languagesOne = await client.ExecuteNexusOperationAsync(
             svc => svc.GetLanguages(new INexusRemoteGreetingService.GetLanguagesInput(false, userIdOne)));

src/NexusMessaging/OnDemandPattern/Handler/GreetingWorkflow.workflow.cs

@@ -17,7 +17,6 @@ public class GreetingWorkflow
     private Language currentLanguage = Language.English;
     private bool approved;
     private string approvedBy = string.Empty;
-    private string? approvalContext;
 
     [WorkflowRun]
     public async Task<string> RunAsync(string userId)
@@ -80,11 +79,4 @@ public Task ApproveAsync(string name)
         approvedBy = name;
         return Task.CompletedTask;
     }
-
-    [WorkflowSignal]
-    public Task AttachApprovalContextAsync(string note)
-    {
-        approvalContext = note;
-        return Task.CompletedTask;
-    }
 }