Adding rich backwards compatibility support to SDK

Directory.Packages.props

@@ -15,6 +15,7 @@
     <PackageVersion Include="Grpc.Core.Testing" Version="2.46.6" />
     <PackageVersion Include="Grpc.Net.Client" Version="2.76.0" />
     <PackageVersion Include="Grpc.Net.ClientFactory" Version="2.76.0" />
+    <PackageVersion Include="Grpc.Reflection" Version="2.80.0" />
     <PackageVersion Include="Grpc.Tools" Version="2.78.0" />
     <PackageVersion Include="Microsoft.AspNetCore.Mvc.Testing" Version="8.0.24" Condition="'$(TargetFramework)' == 'net8.0'" />
     <PackageVersion Include="Microsoft.AspNetCore.Mvc.Testing" Version="9.0.13" Condition="'$(TargetFramework)' == 'net9.0'" />

all.sln

@@ -264,6 +264,10 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Dapr.AI.Microsoft.Extension
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Dapr.DistributedLock.Test", "test\Dapr.DistributedLock.Test\Dapr.DistributedLock.Test.csproj", "{2B8E9CAD-F9A2-43B9-BB1C-619CF64476A0}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Dapr.Common.Generators", "src\Dapr.Common.Generators\Dapr.Common.Generators.csproj", "{DA1F9FE7-6041-4581-B9AD-685034869CE8}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Dapr.Common.Generators.Tests", "test\Dapr.Common.Generators.Tests\Dapr.Common.Generators.Tests.csproj", "{E015C5ED-F93F-4DB6-BA01-BC59B7859A60}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -1558,6 +1562,30 @@ Global
 		{2B8E9CAD-F9A2-43B9-BB1C-619CF64476A0}.Release|x64.Build.0 = Release|Any CPU
 		{2B8E9CAD-F9A2-43B9-BB1C-619CF64476A0}.Release|x86.ActiveCfg = Release|Any CPU
 		{2B8E9CAD-F9A2-43B9-BB1C-619CF64476A0}.Release|x86.Build.0 = Release|Any CPU
+		{DA1F9FE7-6041-4581-B9AD-685034869CE8}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{DA1F9FE7-6041-4581-B9AD-685034869CE8}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{DA1F9FE7-6041-4581-B9AD-685034869CE8}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{DA1F9FE7-6041-4581-B9AD-685034869CE8}.Debug|x64.Build.0 = Debug|Any CPU
+		{DA1F9FE7-6041-4581-B9AD-685034869CE8}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{DA1F9FE7-6041-4581-B9AD-685034869CE8}.Debug|x86.Build.0 = Debug|Any CPU
+		{DA1F9FE7-6041-4581-B9AD-685034869CE8}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{DA1F9FE7-6041-4581-B9AD-685034869CE8}.Release|Any CPU.Build.0 = Release|Any CPU
+		{DA1F9FE7-6041-4581-B9AD-685034869CE8}.Release|x64.ActiveCfg = Release|Any CPU
+		{DA1F9FE7-6041-4581-B9AD-685034869CE8}.Release|x64.Build.0 = Release|Any CPU
+		{DA1F9FE7-6041-4581-B9AD-685034869CE8}.Release|x86.ActiveCfg = Release|Any CPU
+		{DA1F9FE7-6041-4581-B9AD-685034869CE8}.Release|x86.Build.0 = Release|Any CPU
+		{E015C5ED-F93F-4DB6-BA01-BC59B7859A60}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{E015C5ED-F93F-4DB6-BA01-BC59B7859A60}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{E015C5ED-F93F-4DB6-BA01-BC59B7859A60}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{E015C5ED-F93F-4DB6-BA01-BC59B7859A60}.Debug|x64.Build.0 = Debug|Any CPU
+		{E015C5ED-F93F-4DB6-BA01-BC59B7859A60}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{E015C5ED-F93F-4DB6-BA01-BC59B7859A60}.Debug|x86.Build.0 = Debug|Any CPU
+		{E015C5ED-F93F-4DB6-BA01-BC59B7859A60}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{E015C5ED-F93F-4DB6-BA01-BC59B7859A60}.Release|Any CPU.Build.0 = Release|Any CPU
+		{E015C5ED-F93F-4DB6-BA01-BC59B7859A60}.Release|x64.ActiveCfg = Release|Any CPU
+		{E015C5ED-F93F-4DB6-BA01-BC59B7859A60}.Release|x64.Build.0 = Release|Any CPU
+		{E015C5ED-F93F-4DB6-BA01-BC59B7859A60}.Release|x86.ActiveCfg = Release|Any CPU
+		{E015C5ED-F93F-4DB6-BA01-BC59B7859A60}.Release|x86.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -1681,11 +1709,13 @@ Global
 		{01A20A89-53A1-4D5B-B563-89E157718474} = {8462B106-175A-423A-BA94-BE0D39D0BD8E}
 		{7B14879F-156B-417E-ACA3-0B5A69CC2F39} = {8462B106-175A-423A-BA94-BE0D39D0BD8E}
 		{A1B2C3D4-E5F6-7890-ABCD-EF1234567890} = {8462B106-175A-423A-BA94-BE0D39D0BD8E}
+		{8777EAD2-419B-4683-826A-82B7C1F4F69F} = {8462B106-175A-423A-BA94-BE0D39D0BD8E}
+		{C6948155-C70C-4C03-A733-0624402AEC97} = {8462B106-175A-423A-BA94-BE0D39D0BD8E}
 		{6C77A2C4-0A96-4B90-AFEA-16E86A906259} = {BF3ED6BF-ADF3-4D25-8E89-02FB8D945CA9}
 		{86CBB08F-601A-4B0B-87BF-383D391A961C} = {0AF0FE8D-C234-4F04-8514-32206ACE01BD}
 		{2B8E9CAD-F9A2-43B9-BB1C-619CF64476A0} = {0AF0FE8D-C234-4F04-8514-32206ACE01BD}
-		{C6948155-C70C-4C03-A733-0624402AEC97} = {8462B106-175A-423A-BA94-BE0D39D0BD8E}
-		{8777EAD2-419B-4683-826A-82B7C1F4F69F} = {8462B106-175A-423A-BA94-BE0D39D0BD8E}
+		{DA1F9FE7-6041-4581-B9AD-685034869CE8} = {27C5D71D-0721-4221-9286-B94AB07B58CF}
+		{E015C5ED-F93F-4DB6-BA01-BC59B7859A60} = {0AF0FE8D-C234-4F04-8514-32206ACE01BD}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {65220BF2-EAE1-4CB2-AA58-EBE80768CB40}

src/Dapr.AI/Conversation/DaprConversationClientBuilder.cs

@@ -37,6 +37,7 @@ public override DaprConversationClient Build()
     {
         var daprClientDependencies = BuildDaprClientDependencies(typeof(DaprConversationClient).Assembly);
         var client = new Autogenerated.DaprClient(daprClientDependencies.channel);
-        return new DaprConversationGrpcClient(client, daprClientDependencies.httpClient, daprClientDependencies.daprApiToken);
+        IDaprRuntimeCapabilities runtimeCapabilities = new DaprRuntimeCapabilities(daprClientDependencies.channel);
+        return new DaprConversationGrpcClient(client, daprClientDependencies.httpClient, runtimeCapabilities, daprClientDependencies.daprApiToken);
     }
 }

src/Dapr.AI/Conversation/DaprConversationGrpcClient.cs

@@ -22,14 +22,18 @@ namespace Dapr.AI.Conversation;
 /// </summary>
 /// <param name="client">The Dapr client.</param>
 /// <param name="httpClient">The HTTP client used by the client for calling the Dapr runtime.</param>
+/// <param name="runtimeCapabilities">Used to determine which gRPC API variants the connected Dapr runtime supports.</param>
 /// <param name="daprApiToken">An optional token required to send requests to the Dapr sidecar.</param>
 [Experimental("DAPR_CONVERSATION",
     UrlFormat = "https://docs.dapr.io/developing-applications/building-blocks/conversation/conversation-overview/")]
 internal sealed class DaprConversationGrpcClient(
     Autogenerated.Dapr.DaprClient client,
     HttpClient httpClient,
+    IDaprRuntimeCapabilities runtimeCapabilities,
     string? daprApiToken = null) : DaprConversationClient(client, httpClient, daprApiToken: daprApiToken)
 {
+    private readonly IDaprRuntimeCapabilities runtimeCapabilities = runtimeCapabilities;
+
     /// <inheritdoc />
     public override async Task<ConversationResponse> ConverseAsync(IReadOnlyList<ConversationInput> inputs,
         ConversationOptions options, CancellationToken cancellationToken = default)

src/Dapr.Client/Dapr.Client.csproj

@@ -3,6 +3,9 @@
   <!-- Additional Nuget package properties. -->
   <PropertyGroup>
     <Description>This package contains the reference assemblies for developing services using Dapr.</Description>
+    <!-- Enables the DaprVersionAwareGenerator to emit IVersionAwareDaprClient and
+         VersionAwareDaprClient for this project's gRPC client. -->
+    <IsDaprSdkProject>true</IsDaprSdkProject>
   </PropertyGroup>
 
   <ItemGroup>
@@ -15,6 +18,10 @@
   <ItemGroup>
     <ProjectReference Include="..\Dapr.Protos\Dapr.Protos.csproj" />
     <ProjectReference Include="..\Dapr.Common\Dapr.Common.csproj" />
+    <!-- Generator reference: outputs IVersionAwareDaprClient + VersionAwareDaprClient -->
+    <ProjectReference Include="..\Dapr.Common.Generators\Dapr.Common.Generators.csproj"
+                      OutputItemType="Analyzer"
+                      ReferenceOutputAssembly="false" />
   </ItemGroup>
 
 </Project>

src/Dapr.Client/DaprClientBuilder.cs

@@ -16,6 +16,7 @@ namespace Dapr.Client;
 using System;
 using System.Net.Http;
 using System.Text.Json;
+using Common;
 using Grpc.Net.Client;
 using Autogenerated = Autogen.Grpc.v1;
 
@@ -57,7 +58,16 @@ public DaprClientBuilder()
     // property exposed for testing purposes
     internal GrpcChannelOptions GrpcChannelOptions { get; private set; }
     internal string DaprApiToken { get; private set; }
-    internal TimeSpan Timeout { get; private set; } 
+    internal TimeSpan Timeout { get; private set; }
+    // Allows tests to inject a pre-configured IDaprRuntimeCapabilities instead of
+    // creating DaprRuntimeCapabilities, which requires a live gRPC reflection endpoint.
+    internal IDaprRuntimeCapabilities RuntimeCapabilitiesOverride { get; private set; }
+
+    internal DaprClientBuilder UseRuntimeCapabilities(IDaprRuntimeCapabilities capabilities)
+    {
+        this.RuntimeCapabilitiesOverride = capabilities;
+        return this;
+    }
 
     /// <summary>
     /// Overrides the HTTP endpoint used by <see cref="DaprClient" /> for communicating with the Dapr runtime.
@@ -174,16 +184,16 @@ public DaprClient Build()
 
         var channel = GrpcChannel.ForAddress(this.GrpcEndpoint, this.GrpcChannelOptions);
         var client = new Autogenerated.Dapr.DaprClient(channel);
-
+        IDaprRuntimeCapabilities runtimeCapabilities = this.RuntimeCapabilitiesOverride ?? new DaprRuntimeCapabilities(channel);
 
         var apiTokenHeader = DaprClient.GetDaprApiTokenHeader(this.DaprApiToken);
         var httpClient = HttpClientFactory is object ? HttpClientFactory() : new HttpClient();
-            
+
         if (this.Timeout > TimeSpan.Zero)
         {
             httpClient.Timeout = this.Timeout;
         }
 
-        return new DaprClientGrpc(channel, client, httpClient, httpEndpoint, this.JsonSerializerOptions, apiTokenHeader);
+        return new DaprClientGrpc(channel, client, httpClient, httpEndpoint, this.JsonSerializerOptions, apiTokenHeader, runtimeCapabilities);
     }
-}
+}

src/Dapr.Client/DaprClientGrpc.cs

@@ -13,6 +13,7 @@
 
 namespace Dapr.Client;
 
+using Common;
 using Crypto;
 using System;
 using System.Buffers;
@@ -48,6 +49,7 @@ internal class DaprClientGrpc : DaprClient
     private readonly GrpcChannel channel;
     private readonly Autogenerated.Dapr.DaprClient client;
     private readonly KeyValuePair<string, string>? apiTokenHeader;
+    private readonly IVersionAwareDaprClient versionAwareClient;
 
     // property exposed for testing purposes
     internal Autogenerated.Dapr.DaprClient Client => client;
@@ -60,14 +62,16 @@ internal DaprClientGrpc(
         HttpClient httpClient,
         Uri httpEndpoint,
         JsonSerializerOptions jsonSerializerOptions,
-        KeyValuePair<string, string>? apiTokenHeader)
+        KeyValuePair<string, string>? apiTokenHeader,
+        IDaprRuntimeCapabilities runtimeCapabilities)
     {
         this.channel = channel;
         this.client = inner;
         this.httpClient = httpClient;
         this.httpEndpoint = httpEndpoint;
         this.jsonSerializerOptions = jsonSerializerOptions;
         this.apiTokenHeader = apiTokenHeader;
+        this.versionAwareClient = new VersionAwareDaprClient(inner, runtimeCapabilities);
 
         this.httpClient.DefaultRequestHeaders.UserAgent.Add(UserAgent());
     }
@@ -246,7 +250,7 @@ private async Task<BulkPublishResponse<TValue>> MakeBulkPublishRequest<TValue>(
 
         try
         {
-            var response = await client.BulkPublishEventAsync(envelope, options);
+            var response = await versionAwareClient.BulkPublishEventAsync(envelope, options);
 
             List<BulkPublishResponseFailedEntry<TValue>> failedEntries = [];