First pass at Grpc.StatusProto API

Grpc.DotNet.sln

@@ -140,6 +140,10 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Grpc.HealthCheck.Tests", "t
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Grpc.Reflection.Tests", "test\Grpc.Reflection.Tests\Grpc.Reflection.Tests.csproj", "{857C5B4B-E2A8-4ACA-98FB-5E592E2224CC}"
 EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Grpc.StatusProto", "src\Grpc.StatusProto\Grpc.StatusProto.csproj", "{C01E4F44-9AB0-4478-A453-C88CCB49A4F1}"
+EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Grpc.StatusProto.Tests", "test\Grpc.StatusProto.Tests\Grpc.StatusProto.Tests.csproj", "{E49FA5BF-4D67-4C95-9543-8E9FCEAF3609}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -302,6 +306,14 @@ Global
 		{857C5B4B-E2A8-4ACA-98FB-5E592E2224CC}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{857C5B4B-E2A8-4ACA-98FB-5E592E2224CC}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{857C5B4B-E2A8-4ACA-98FB-5E592E2224CC}.Release|Any CPU.Build.0 = Release|Any CPU
+		{C01E4F44-9AB0-4478-A453-C88CCB49A4F1}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{C01E4F44-9AB0-4478-A453-C88CCB49A4F1}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{C01E4F44-9AB0-4478-A453-C88CCB49A4F1}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{C01E4F44-9AB0-4478-A453-C88CCB49A4F1}.Release|Any CPU.Build.0 = Release|Any CPU
+		{E49FA5BF-4D67-4C95-9543-8E9FCEAF3609}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{E49FA5BF-4D67-4C95-9543-8E9FCEAF3609}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{E49FA5BF-4D67-4C95-9543-8E9FCEAF3609}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{E49FA5BF-4D67-4C95-9543-8E9FCEAF3609}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -355,6 +367,8 @@ Global
 		{B4153E7F-5CF3-4DFB-A9D1-5E77A2FB2C48} = {8C62055F-8CD7-4859-9001-634D544DF2AE}
 		{25544326-C145-4D05-A4C3-AC7D59E17196} = {CECC4AE8-9C4E-4727-939B-517CC2E58D65}
 		{857C5B4B-E2A8-4ACA-98FB-5E592E2224CC} = {CECC4AE8-9C4E-4727-939B-517CC2E58D65}
+		{C01E4F44-9AB0-4478-A453-C88CCB49A4F1} = {8C62055F-8CD7-4859-9001-634D544DF2AE}
+		{E49FA5BF-4D67-4C95-9543-8E9FCEAF3609} = {CECC4AE8-9C4E-4727-939B-517CC2E58D65}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {CD5C2B19-49B4-480A-990C-36D98A719B07}

build/dependencies.props

@@ -1,6 +1,7 @@
 <Project>
   <PropertyGroup>
     <BenchmarkDotNetPackageVersion>0.13.1</BenchmarkDotNetPackageVersion>
+    <GoogleApiCommonProtos>2.10.0</GoogleApiCommonProtos>
     <GoogleApisAuthPackageVersion>1.46.0</GoogleApisAuthPackageVersion>
     <GoogleProtobufPackageVersion>3.23.1</GoogleProtobufPackageVersion>
     <GrpcDotNetPackageVersion>2.52.0</GrpcDotNetPackageVersion>  <!-- Used by example projects -->

src/Grpc.StatusProto/Grpc.StatusProto.csproj

@@ -0,0 +1,23 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <Description>gRPC C# API for error handling using status.proto</Description>
+    <PackageTags>gRPC RPC HTTP/2</PackageTags>
+
+    <IsGrpcPublishedPackage>true</IsGrpcPublishedPackage>
+    <GenerateDocumentationFile>true</GenerateDocumentationFile>
+    <TargetFrameworks>net462;netstandard2.0;netstandard2.1</TargetFrameworks>
+    <PackageReadmeFile>README.md</PackageReadmeFile>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Google.Api.CommonProtos" Version="$(GoogleApiCommonProtos)" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <None Include="README.md" Pack="true" PackagePath="\" />
+
+    <ProjectReference Include="..\Grpc.Core.Api\Grpc.Core.Api.csproj" />
+  </ItemGroup>
+
+</Project>

src/Grpc.StatusProto/MetadataExtensions.cs

@@ -0,0 +1,75 @@
+// Copyright 2023 gRPC 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 Google.Protobuf;
+using Grpc.Core;
+
+namespace Grpc.StatusProto;
+
+/// <summary>
+/// Extension methods for the Grpc.Core.Metadata
+/// </summary>
+public static class MetadataExtensions  
+{
+    /// <summary>
+    /// Name of key in the metadata for the binary encoding of
+    /// <see cref="Google.Rpc.Status"/>
+    /// </summary>
+    public const string StatusDetailsTrailerName = "grpc-status-details-bin";
+
+    /// <summary>
+    /// Get the <see cref="Google.Rpc.Status"/> from the metadata.
+    /// If the metadata received contains duplicate status details then the last one found
+    /// is the one that is returned.
+    /// </summary>
+    /// <param name="metadata"></param>
+    /// <returns>
+    /// The found <see cref="Google.Rpc.Status"/> or null if it was
+    /// not present or could the data could not be parsed.
+    /// </returns>
+    public static Google.Rpc.Status? GetRpcStatus(this Metadata metadata)
+    {
+        var entry = metadata.LastOrDefault(t => t.Key == StatusDetailsTrailerName);
+        if (entry is null)
+        {
+            return null;
+        }
+        try
+        {
+            return Google.Rpc.Status.Parser.ParseFrom(entry.ValueBytes);
+        }
+        catch
+        {
+            // If the message is malformed, just report there's no information.
+            return null;
+        }
+    }
+
+    /// <summary>
+    /// Add <see cref="Google.Rpc.Status"/> to the metadata.
+    /// Any existing status in the metadata will be overwritten.
+    /// </summary>
+    /// <param name="metadata"></param>
+    /// <param name="status">Status to add</param>
+    public static void SetRpcStatus(this Metadata metadata, Google.Rpc.Status status)
+    {
+        var entry = metadata.Get(StatusDetailsTrailerName);
+        while (entry is not null)
+        {
+            metadata.Remove(entry);
+            entry = metadata.Get(StatusDetailsTrailerName);
+        }
+        metadata.Add(StatusDetailsTrailerName, status.ToByteArray());
+    }
+}