Add Roslyn analyzer for workflows

Directory.Packages.props

@@ -20,6 +20,7 @@
     <PackageVersion Include="Microsoft.CodeAnalysis.Analyzers" Version="3.3.4" />
     <PackageVersion Include="Microsoft.CodeAnalysis.Common" Version="4.8.0" />
     <PackageVersion Include="Microsoft.CodeAnalysis.CSharp" Version="4.8.0" />
+    <PackageVersion Include="Microsoft.CodeAnalysis.CSharp.Analyzer.Testing" Version="1.1.2" />
     <PackageVersion Include="Microsoft.CodeAnalysis.CSharp.SourceGenerators.Testing" Version="1.1.2" />
     <PackageVersion Include="Microsoft.CodeAnalysis.CSharp.SourceGenerators.Testing.XUnit" Version="1.1.2" />
     <PackageVersion Include="Microsoft.CodeAnalysis.CSharp.Workspaces" Version="4.8.0" />

all.sln

@@ -155,6 +155,10 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "JobsSample", "examples\Jobs
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Dapr.Workflow.Test", "test\Dapr.Workflow.Test\Dapr.Workflow.Test.csproj", "{E90114C6-86FC-43B8-AE5C-D9273CF21FE4}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Dapr.Workflow.Analyzers", "src\Dapr.Workflow.Analyzers\Dapr.Workflow.Analyzers.csproj", "{55A7D436-CC8C-47E6-B43A-DFE32E0FE38C}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Dapr.Workflow.Analyzers.Test", "test\Dapr.Workflow.Analyzers.Test\Dapr.Workflow.Analyzers.Test.csproj", "{CE0D5FEB-F6DB-4EB8-B8A9-6A4A32944539}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -403,6 +407,14 @@ Global
 		{E90114C6-86FC-43B8-AE5C-D9273CF21FE4}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{E90114C6-86FC-43B8-AE5C-D9273CF21FE4}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{E90114C6-86FC-43B8-AE5C-D9273CF21FE4}.Release|Any CPU.Build.0 = Release|Any CPU
+		{55A7D436-CC8C-47E6-B43A-DFE32E0FE38C}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{55A7D436-CC8C-47E6-B43A-DFE32E0FE38C}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{55A7D436-CC8C-47E6-B43A-DFE32E0FE38C}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{55A7D436-CC8C-47E6-B43A-DFE32E0FE38C}.Release|Any CPU.Build.0 = Release|Any CPU
+		{CE0D5FEB-F6DB-4EB8-B8A9-6A4A32944539}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{CE0D5FEB-F6DB-4EB8-B8A9-6A4A32944539}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{CE0D5FEB-F6DB-4EB8-B8A9-6A4A32944539}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{CE0D5FEB-F6DB-4EB8-B8A9-6A4A32944539}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -477,6 +489,8 @@ Global
 		{D9697361-232F-465D-A136-4561E0E88488} = {D687DDC4-66C5-4667-9E3A-FD8B78ECAA78}
 		{9CAF360E-5AD3-4C4F-89A0-327EEB70D673} = {D9697361-232F-465D-A136-4561E0E88488}
 		{E90114C6-86FC-43B8-AE5C-D9273CF21FE4} = {DD020B34-460F-455F-8D17-CF4A949F100B}
+		{55A7D436-CC8C-47E6-B43A-DFE32E0FE38C} = {27C5D71D-0721-4221-9286-B94AB07B58CF}
+		{CE0D5FEB-F6DB-4EB8-B8A9-6A4A32944539} = {DD020B34-460F-455F-8D17-CF4A949F100B}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {65220BF2-EAE1-4CB2-AA58-EBE80768CB40}

src/Dapr.Workflow.Analyzers/AnalyzerReleases.Shipped.md

@@ -0,0 +1,8 @@
+## Release 1.16
+
+### New Rules
+
+Rule ID | Category | Severity | Notes
+--------|----------|----------|--------------------
+DAPR1001| Usage    | Warning    | The workflow class '{0}' is not registered
+DAPR1002| Usage    | Warning    | The workflow activity class '{0}' is not registered

src/Dapr.Workflow.Analyzers/AnalyzerReleases.Unshipped.md

@@ -0,0 +1,3 @@
+; Unshipped analyzer release
+; https://github.com/dotnet/roslyn-analyzers/blob/main/src/Microsoft.CodeAnalysis.Analyzers/ReleaseTrackingAnalyzers.Help.md
+

src/Dapr.Workflow.Analyzers/Dapr.Workflow.Analyzers.csproj

@@ -0,0 +1,43 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>netstandard2.0</TargetFramework>
+    <TargetFrameworks></TargetFrameworks>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <EnforceExtendedAnalyzerRules>true</EnforceExtendedAnalyzerRules>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.CodeAnalysis.CSharp.Workspaces" />
+  </ItemGroup>
+
+  <PropertyGroup>
+    <!-- Suppress false-positive error NU5128 when packing analyzers with no lib/ref files. -->
+    <SuppressDependenciesWhenPacking>true</SuppressDependenciesWhenPacking>
+
+    <!-- Suppress generation of symbol package (.snupkg). -->
+    <IncludeSymbols>false</IncludeSymbols>
+
+    <!-- Do not include the generator as a lib dependency -->
+    <IncludeBuildOutput>false</IncludeBuildOutput>
+
+    <!-- Additional NuGet package properties. -->
+    <Description>This package contains analyzers for interacting with Dapr workflows.</Description>
+    <PackageTags>$(PackageTags)</PackageTags>
+  </PropertyGroup>
+
+  <ItemGroup>    
+    <None Include="$(OutputPath)\$(AssemblyName).dll" Pack="true" PackagePath="analyzers/dotnet/cs" Visible="false" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <AdditionalFiles Include="AnalyzerReleases.Shipped.md" />
+    <AdditionalFiles Include="AnalyzerReleases.Unshipped.md" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <InternalsVisibleTo Include="$(AssemblyName).Test, PublicKey=0024000004800000940000000602000000240000525341310004000001000100b1f597635c44597fcecb493e2b1327033b29b1a98ac956a1a538664b68f87d45fbaada0438a15a6265e62864947cc067d8da3a7d93c5eb2fcbb850e396c8684dba74ea477d82a1bbb18932c0efb30b64ff1677f85ae833818707ac8b49ad8062ca01d2c89d8ab1843ae73e8ba9649cd28666b539444dcdee3639f95e2a099bb2"/>
+  </ItemGroup>
+
+</Project>

src/Dapr.Workflow.Analyzers/WorkflowActivityRegistrationCodeFixProvider.cs

@@ -0,0 +1,124 @@
+using System.Collections.Immutable;
+using System.Composition;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CodeActions;
+using Microsoft.CodeAnalysis.CodeFixes;
+using Microsoft.CodeAnalysis.CSharp;
+using Microsoft.CodeAnalysis.CSharp.Syntax;
+using Microsoft.CodeAnalysis.Formatting;
+
+namespace Dapr.Workflow.Analyzers;
+
+/// <summary>
+/// Provides code fixes for DAPR1002 diagnostic.
+/// </summary>
+[ExportCodeFixProvider(LanguageNames.CSharp, Name = nameof(WorkflowActivityRegistrationCodeFixProvider))]
+[Shared]
+public class WorkflowActivityRegistrationCodeFixProvider : CodeFixProvider
+{
+    /// <summary>
+    /// Gets the diagnostic IDs that this provider can fix.
+    /// </summary>
+    public override ImmutableArray<string> FixableDiagnosticIds => ImmutableArray.Create("DAPR1002");
+
+    /// <summary>
+    /// Registers the code fix for the diagnostic.
+    /// </summary>
+    public override Task RegisterCodeFixesAsync(CodeFixContext context)
+    {
+        var title = "Register workflow activity";
+        context.RegisterCodeFix(
+            CodeAction.Create(
+                title,
+                createChangedDocument: c => RegisterWorkflowActivityAsync(context.Document, context.Diagnostics.First(), c),
+                equivalenceKey: title),
+            context.Diagnostics);
+        return Task.CompletedTask;
+    }
+
+    private async Task<Document> RegisterWorkflowActivityAsync(Document document, Diagnostic diagnostic, CancellationToken cancellationToken)
+    {
+        var root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
+        var diagnosticSpan = diagnostic.Location.SourceSpan;
+
+        var oldInvocation = root?.FindToken(diagnosticSpan.Start).Parent?.AncestorsAndSelf().OfType<InvocationExpressionSyntax>().First();
+
+        if (oldInvocation is null)
+            return document;
+
+        if (root == null || oldInvocation == null)
+            return document;
+
+        // Extract the workflow activity type name
+        var workflowActivityType = oldInvocation.ArgumentList.Arguments.FirstOrDefault()?.Expression.ToString();
+
+        if (string.IsNullOrEmpty(workflowActivityType))
+            return document;
+
+        // Get the compilation
+        var compilation = await document.Project.GetCompilationAsync(cancellationToken).ConfigureAwait(false);
+
+        if (compilation == null)
+            return document;
+
+        InvocationExpressionSyntax? addDaprWorkflowInvocation = null;
+        SyntaxNode? targetRoot = null;
+        Document? targetDocument = null;
+
+        // Iterate through all syntax trees in the compilation
+        foreach (var syntaxTree in compilation.SyntaxTrees)
+        {
+            var syntaxRoot = await syntaxTree.GetRootAsync(cancellationToken).ConfigureAwait(false);
+
+            addDaprWorkflowInvocation = syntaxRoot.DescendantNodes()
+                .OfType<InvocationExpressionSyntax>()
+                .FirstOrDefault(invocation => invocation.Expression is MemberAccessExpressionSyntax memberAccess &&
+                                              memberAccess.Name.Identifier.Text == "AddDaprWorkflow");
+
+            if (addDaprWorkflowInvocation != null)
+            {
+                targetRoot = syntaxRoot;
+                targetDocument = document.Project.GetDocument(syntaxTree);
+                break;
+            }
+        }
+
+        if (addDaprWorkflowInvocation == null || targetRoot == null || targetDocument == null)
+            return document;
+
+        // Find the options lambda block
+        var optionsLambda = addDaprWorkflowInvocation.ArgumentList.Arguments
+            .Select(arg => arg.Expression)
+            .OfType<SimpleLambdaExpressionSyntax>()
+            .FirstOrDefault();
+
+        // Extract the parameter name from the lambda expression
+        var parameterName = optionsLambda?.Parameter.Identifier.Text;
+
+        // Create the new workflow registration statement
+        var registerWorkflowStatement = SyntaxFactory.ParseStatement($"{parameterName}.RegisterActivity<{workflowActivityType}>();");
+
+        if (optionsLambda == null || optionsLambda.Body is not BlockSyntax optionsBlock)
+            return document;
+
+        // Add the new registration statement to the options block
+        var newOptionsBlock = optionsBlock.AddStatements(registerWorkflowStatement);
+
+        // Replace the old options block with the new one
+        var newRoot = targetRoot.ReplaceNode(optionsBlock, newOptionsBlock);
+
+        // Format the new root.
+        newRoot = Formatter.Format(newRoot, document.Project.Solution.Workspace);
+
+        return targetDocument.WithSyntaxRoot(newRoot);
+    }
+
+    /// <summary>
+    /// Gets the FixAllProvider for this code fix provider.
+    /// </summary>
+    /// <returns>The FixAllProvider instance.</returns>
+    public override FixAllProvider? GetFixAllProvider()
+    {
+        return WellKnownFixAllProviders.BatchFixer;
+    }
+}