Added workflow example: Fan out/fan in

Directory.Packages.props

@@ -29,10 +29,11 @@
         <PackageVersion Include="Microsoft.Extensions.Configuration" Version="6.0.1" />
         <PackageVersion Include="Microsoft.Extensions.Configuration.Abstractions" Version="6.0.0" />
         <PackageVersion Include="Microsoft.Extensions.DependencyInjection" Version="6.0.1" />
-      <PackageVersion Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="6.0.0" />
+        <PackageVersion Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="6.0.0" />
+        <PackageVersion Include="Microsoft.Extensions.Hosting" Version="6.0.1" />
+        <PackageVersion Include="Microsoft.Extensions.Http" Version="6.0.0" />
         <PackageVersion Include="Microsoft.Extensions.Logging" Version="6.0.0" />
         <PackageVersion Include="Microsoft.Extensions.Logging.Abstractions" Version="6.0.4" />
-        <PackageVersion Include="Microsoft.Extensions.Http" Version="6.0.0" />
         <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="16.8.3" />
         <PackageVersion Include="Microsoft.SourceLink.GitHub" Version="1.1.1" />
         <PackageVersion Include="MinVer" Version="2.3.0" />

all.sln

@@ -119,11 +119,14 @@ 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}") = "WorkflowFanOutFanIn", "examples\Workflow\WorkflowFanOutFanIn\WorkflowFanOutFanIn.csproj", "{D83B27F3-4401-42F5-843E-147566B4999A}"
+EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Dapr.Messaging.Test", "test\Dapr.Messaging.Test\Dapr.Messaging.Test.csproj", "{4E04EB35-7FD2-4FDB-B09A-F75CE24053B9}"
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Dapr.Messaging", "src\Dapr.Messaging\Dapr.Messaging.csproj", "{0EAE36A1-B578-4F13-A113-7A477ECA1BDA}"
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "StreamingSubscriptionExample", "examples\Client\PublishSubscribe\StreamingSubscriptionExample\StreamingSubscriptionExample.csproj", "{290D1278-F613-4DF3-9DF5-F37E38CDC363}"
+EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Dapr.Jobs", "src\Dapr.Jobs\Dapr.Jobs.csproj", "{C8BB6A85-A7EA-40C0-893D-F36F317829B3}"
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Dapr.Jobs.Test", "test\Dapr.Jobs.Test\Dapr.Jobs.Test.csproj", "{BF9828E9-5597-4D42-AA6E-6E6C12214204}"
@@ -316,6 +319,10 @@ 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
+		{D83B27F3-4401-42F5-843E-147566B4999A}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{D83B27F3-4401-42F5-843E-147566B4999A}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{D83B27F3-4401-42F5-843E-147566B4999A}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{D83B27F3-4401-42F5-843E-147566B4999A}.Release|Any CPU.Build.0 = Release|Any CPU
 		{4E04EB35-7FD2-4FDB-B09A-F75CE24053B9}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
 		{4E04EB35-7FD2-4FDB-B09A-F75CE24053B9}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{4E04EB35-7FD2-4FDB-B09A-F75CE24053B9}.Release|Any CPU.ActiveCfg = Release|Any CPU
@@ -396,6 +403,7 @@ 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}
+		{D83B27F3-4401-42F5-843E-147566B4999A} = {BF3ED6BF-ADF3-4D25-8E89-02FB8D945CA9}
 		{4E04EB35-7FD2-4FDB-B09A-F75CE24053B9} = {DD020B34-460F-455F-8D17-CF4A949F100B}
 		{0EAE36A1-B578-4F13-A113-7A477ECA1BDA} = {27C5D71D-0721-4221-9286-B94AB07B58CF}
 		{290D1278-F613-4DF3-9DF5-F37E38CDC363} = {0EF6EA64-D7C3-420D-9890-EAE8D54A57E6}

examples/Workflow/WorkflowFanOutFanIn/Activities/NotifyActivity.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 WorkflowFanOutFanIn.Activities;
+
+internal sealed class NotifyActivity : WorkflowActivity<string, object?>
+{
+    /// <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<object?> RunAsync(WorkflowActivityContext context, string input)
+    {
+        Console.WriteLine(input);
+        return Task.FromResult<object?>(null);
+    }
+}

examples/Workflow/WorkflowFanOutFanIn/Program.cs

@@ -0,0 +1,40 @@
+// ------------------------------------------------------------------------
+// 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 WorkflowFanOutFanIn.Activities;
+using WorkflowFanOutFanIn.Workflows;
+
+var builder = Host.CreateDefaultBuilder(args).ConfigureServices(services =>
+{
+    services.AddDaprWorkflow(options =>
+    {
+        options.RegisterWorkflow<DemoWorkflow>();
+        options.RegisterActivity<NotifyActivity>();
+    });
+});
+
+var host = builder.Build();
+await host.StartAsync();
+
+await using var scope = host.Services.CreateAsyncScope();
+var daprWorkflowClient = scope.ServiceProvider.GetRequiredService<DaprWorkflowClient>();
+
+var instanceId = $"workflow-demo-{Guid.NewGuid().ToString()[..8]}";
+await daprWorkflowClient.ScheduleNewWorkflowAsync(nameof(DemoWorkflow), instanceId, "test input");
+
+await daprWorkflowClient.WaitForWorkflowCompletionAsync(instanceId);
+var state = await daprWorkflowClient.GetWorkflowStateAsync(instanceId);
+Console.WriteLine($"Workflow state: {state.RuntimeStatus}");

examples/Workflow/WorkflowFanOutFanIn/WorkflowFanOutFanIn.csproj

@@ -0,0 +1,18 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+    <PropertyGroup>
+        <OutputType>Exe</OutputType>
+        <TargetFramework>net8.0</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/WorkflowFanOutFanIn/Workflows/DemoWorkflow.cs

@@ -0,0 +1,40 @@
+// ------------------------------------------------------------------------
+// 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 WorkflowFanOutFanIn.Activities;
+
+namespace WorkflowFanOutFanIn.Workflows;
+
+public sealed class DemoWorkflow : Workflow<string, string>
+{
+    /// <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<string> RunAsync(WorkflowContext context, string input)
+    {
+        var tasks = new List<Task>();
+        for (var a = 1; a <= 3; a++)
+        {
+            var task = context.CallActivityAsync(nameof(NotifyActivity), $"calling task {a}");
+            tasks.Add(task);
+        }
+
+        await Task.WhenAll(tasks);
+
+        return "Workflow completed";
+    }
+}