Added workflow sample: Task chaining (#1387)

* Added Workflow Task Chaining example to replace https://github.com/dapr/dotnet-sdk/pull/1206

Signed-off-by: Whit Waldo <whit.waldo@innovian.net>

* Targeting .NET 6, fixed transposition error

Signed-off-by: Whit Waldo <whit.waldo@innovian.net>

* Added missing copyright headers

Signed-off-by: Whit Waldo <whit.waldo@innovian.net>

---------

Signed-off-by: Whit Waldo <whit.waldo@innovian.net>

all.sln

@@ -119,6 +119,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Dapr.Common", "src\Dapr.Com
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Dapr.Common.Test", "test\Dapr.Common.Test\Dapr.Common.Test.csproj", "{CDB47863-BEBD-4841-A807-46D868962521}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "WorkflowTaskChaining", "examples\Workflow\WorkflowTaskChaining\WorkflowTaskChaining.csproj", "{945DD3B7-94E5-435E-B3CB-796C20A652C7}"
+EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "WorkflowSubworkflow", "examples\Workflow\WorkflowSubworkflow\WorkflowSubworkflow.csproj", "{FD3E9371-3134-4235-8E80-32226DFB4B1F}"
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "WorkflowFanOutFanIn", "examples\Workflow\WorkflowFanOutFanIn\WorkflowFanOutFanIn.csproj", "{D83B27F3-4401-42F5-843E-147566B4999A}"
@@ -323,6 +325,10 @@ Global
 		{CDB47863-BEBD-4841-A807-46D868962521}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{CDB47863-BEBD-4841-A807-46D868962521}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{CDB47863-BEBD-4841-A807-46D868962521}.Release|Any CPU.Build.0 = Release|Any CPU
+		{945DD3B7-94E5-435E-B3CB-796C20A652C7}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{945DD3B7-94E5-435E-B3CB-796C20A652C7}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{945DD3B7-94E5-435E-B3CB-796C20A652C7}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{945DD3B7-94E5-435E-B3CB-796C20A652C7}.Release|Any CPU.Build.0 = Release|Any CPU
 		{FD3E9371-3134-4235-8E80-32226DFB4B1F}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
 		{FD3E9371-3134-4235-8E80-32226DFB4B1F}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{FD3E9371-3134-4235-8E80-32226DFB4B1F}.Release|Any CPU.ActiveCfg = Release|Any CPU
@@ -415,6 +421,7 @@ Global
 		{DFBABB04-50E9-42F6-B470-310E1B545638} = {27C5D71D-0721-4221-9286-B94AB07B58CF}
 		{B445B19C-A925-4873-8CB7-8317898B6970} = {27C5D71D-0721-4221-9286-B94AB07B58CF}
 		{CDB47863-BEBD-4841-A807-46D868962521} = {DD020B34-460F-455F-8D17-CF4A949F100B}
+		{945DD3B7-94E5-435E-B3CB-796C20A652C7} = {BF3ED6BF-ADF3-4D25-8E89-02FB8D945CA9}
 		{FD3E9371-3134-4235-8E80-32226DFB4B1F} = {BF3ED6BF-ADF3-4D25-8E89-02FB8D945CA9}
 		{D83B27F3-4401-42F5-843E-147566B4999A} = {BF3ED6BF-ADF3-4D25-8E89-02FB8D945CA9}
 		{00359961-0C50-4BB1-A794-8B06DE991639} = {BF3ED6BF-ADF3-4D25-8E89-02FB8D945CA9}

examples/Workflow/WorkflowTaskChaining/Activities/Step1.cs

@@ -0,0 +1,31 @@
+// ------------------------------------------------------------------------
+// Copyright 2024 The Dapr Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//     http://www.apache.org/licenses/LICENSE-2.0
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// ------------------------------------------------------------------------
+
+using Dapr.Workflow;
+
+namespace WorkflowTaskChaining.Activities;
+
+internal sealed class Step1 : WorkflowActivity<int, int>
+{
+    /// <summary>
+    /// Override to implement async (non-blocking) workflow activity logic.
+    /// </summary>
+    /// <param name="context">Provides access to additional context for the current activity execution.</param>
+    /// <param name="input">The deserialized activity input.</param>
+    /// <returns>The output of the activity as a task.</returns>
+    public override Task<int> RunAsync(WorkflowActivityContext context, int input)
+    {
+        Console.WriteLine($@"Step 1: Received input: {input}.");
+        return Task.FromResult(input + 1);
+    }
+}

examples/Workflow/WorkflowTaskChaining/Activities/Step2.cs

@@ -0,0 +1,31 @@
+// ------------------------------------------------------------------------
+// Copyright 2024 The Dapr Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//     http://www.apache.org/licenses/LICENSE-2.0
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// ------------------------------------------------------------------------
+
+using Dapr.Workflow;
+
+namespace WorkflowTaskChaining.Activities;
+
+internal sealed class Step2 : WorkflowActivity<int, int>
+{
+    /// <summary>
+    /// Override to implement async (non-blocking) workflow activity logic.
+    /// </summary>
+    /// <param name="context">Provides access to additional context for the current activity execution.</param>
+    /// <param name="input">The deserialized activity input.</param>
+    /// <returns>The output of the activity as a task.</returns>
+    public override Task<int> RunAsync(WorkflowActivityContext context, int input)
+    {
+        Console.WriteLine($@"Step 2: Received input: {input}.");
+        return Task.FromResult(input + 2);
+    }
+}

examples/Workflow/WorkflowTaskChaining/Activities/Step3.cs

@@ -0,0 +1,31 @@
+// ------------------------------------------------------------------------
+// Copyright 2024 The Dapr Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//     http://www.apache.org/licenses/LICENSE-2.0
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// ------------------------------------------------------------------------
+
+using Dapr.Workflow;
+
+namespace WorkflowTaskChaining.Activities;
+
+internal sealed class Step3 : WorkflowActivity<int, int>
+{
+    /// <summary>
+    /// Override to implement async (non-blocking) workflow activity logic.
+    /// </summary>
+    /// <param name="context">Provides access to additional context for the current activity execution.</param>
+    /// <param name="input">The deserialized activity input.</param>
+    /// <returns>The output of the activity as a task.</returns>
+    public override Task<int> RunAsync(WorkflowActivityContext context, int input)
+    {
+        Console.WriteLine($@"Step 3: Received input: {input}.");
+        return Task.FromResult(input ^ 2);
+    }
+}

examples/Workflow/WorkflowTaskChaining/Program.cs

@@ -0,0 +1,64 @@
+// ------------------------------------------------------------------------
+// Copyright 2024 The Dapr Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//     http://www.apache.org/licenses/LICENSE-2.0
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// ------------------------------------------------------------------------
+
+using Dapr.Workflow;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
+using WorkflowTaskChaining.Activities;
+using WorkflowTaskChaining.Workflows;
+
+var builder = Host.CreateDefaultBuilder(args).ConfigureServices(services =>
+{
+    services.AddDaprWorkflow(options =>
+    {
+        options.RegisterWorkflow<DemoWorkflow>();
+        options.RegisterActivity<Step1>();
+        options.RegisterActivity<Step2>();
+        options.RegisterActivity<Step3>();
+    });
+});
+
+// Start the app - this is the point where we connect to the Dapr sidecar to listen 
+// for workflow work-items to execute
+using var host = builder.Build();
+await host.StartAsync();
+
+await using var scope = host.Services.CreateAsyncScope();
+var daprWorkflowClient = scope.ServiceProvider.GetRequiredService<DaprWorkflowClient>();
+    
+//Check health
+const int wfInput = 42;
+Console.WriteLine(@"Workflow Started");
+
+var instanceId = $"demo-workflow-{Guid.NewGuid().ToString()[..8]}";
+
+//Start the workflow immediately
+await daprWorkflowClient.ScheduleNewWorkflowAsync(nameof(DemoWorkflow), instanceId, wfInput);
+
+//Get the status of the workflow
+WorkflowState workflowState;
+while (true)
+{
+    workflowState = await daprWorkflowClient.GetWorkflowStateAsync(instanceId, true);
+    Console.WriteLine($@"Workflow status: {workflowState.RuntimeStatus}");
+    if (workflowState.IsWorkflowCompleted)
+        break;
+
+    await Task.Delay(TimeSpan.FromSeconds(1));
+}
+
+//Display the result from the workflow
+var result = string.Join(" ", workflowState.ReadOutputAs<int[]>() ?? Array.Empty<int>());
+Console.WriteLine($@"Workflow result: {result}");
+
+

examples/Workflow/WorkflowTaskChaining/WorkflowTaskChaining.csproj

@@ -0,0 +1,18 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+    <PropertyGroup>
+        <OutputType>Exe</OutputType>
+        <TargetFramework>net6.0</TargetFramework>
+        <ImplicitUsings>enable</ImplicitUsings>
+        <Nullable>enable</Nullable>
+    </PropertyGroup>
+
+    <ItemGroup>
+      <ProjectReference Include="..\..\..\src\Dapr.Workflow\Dapr.Workflow.csproj" />
+    </ItemGroup>
+
+    <ItemGroup>
+      <PackageReference Include="Microsoft.Extensions.Hosting" />
+    </ItemGroup>
+
+</Project>

examples/Workflow/WorkflowTaskChaining/Workflows/DemoWorkflow.cs

@@ -0,0 +1,36 @@
+// ------------------------------------------------------------------------
+// Copyright 2024 The Dapr Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//     http://www.apache.org/licenses/LICENSE-2.0
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// ------------------------------------------------------------------------
+
+using Dapr.Workflow;
+using WorkflowTaskChaining.Activities;
+
+namespace WorkflowTaskChaining.Workflows;
+
+internal sealed class DemoWorkflow : Workflow<int, int[]>
+{
+    /// <summary>
+    /// Override to implement workflow logic.
+    /// </summary>
+    /// <param name="context">The workflow context.</param>
+    /// <param name="input">The deserialized workflow input.</param>
+    /// <returns>The output of the workflow as a task.</returns>
+    public override async Task<int[]> RunAsync(WorkflowContext context, int input)
+    {
+        var result1 = await context.CallActivityAsync<int>(nameof(Step1), input);
+        var result2 = await context.CallActivityAsync<int>(nameof(Step2), result1);
+        var result3 = await context.CallActivityAsync<int>(nameof(Step3), result2);
+        var ret = new int[] { result1, result2, result3 };
+
+        return ret;
+    }
+}

test/Dapr.E2E.Test/DaprCommand.cs

@@ -38,7 +38,7 @@ namespace Dapr.E2E.Test
 
         public void Run()
         {
-            Console.WriteLine($"Running command: {this.Command}");
+            Console.WriteLine($@"Running command: {this.Command}");
             var escapedArgs = Command.Replace("\"", "\\\"");
             var process = new Process()
             {