From e5e00165d4d191f6f6ea9f5b2a6eaf4f67bf5a4c Mon Sep 17 00:00:00 2001
From: Jose <jose@zeroc.com>
Date: Thu, 30 Apr 2026 18:31:17 +0200
Subject: [PATCH] Aggregate Protobuf build telemetry into a single per-build
 report (#4443)

The build-telemetry plug-in ran inside each per-file protoc invocation,
producing N uploads with FileCount=1 instead of one upload describing
the whole compilation.

Generalize ProtocTask to take a `Plugins` item list (matching the shape
of SlicecTask.Generators) and an `AdditionalOptions` parameter, and run
it twice from the targets: per-file for codegen plus per-file dependency
files, then once over all ProtoFile items for the telemetry plug-in.
---
 .../IceRpc.Protobuf.Tools.targets             | 43 ++++++++--
 src/IceRpc.Protobuf.Tools/ProtocTask.cs       | 83 +++++++------------
 2 files changed, 64 insertions(+), 62 deletions(-)

diff --git a/src/IceRpc.Protobuf.Tools/IceRpc.Protobuf.Tools.targets b/src/IceRpc.Protobuf.Tools/IceRpc.Protobuf.Tools.targets
index c44e9d0e6f..bbaf2ae254 100644
--- a/src/IceRpc.Protobuf.Tools/IceRpc.Protobuf.Tools.targets
+++ b/src/IceRpc.Protobuf.Tools/IceRpc.Protobuf.Tools.targets
@@ -26,12 +26,6 @@
     AssemblyFile="$(IceRpcProtobufToolsTaskAssembliesPath)IceRpc.Protobuf.Tools.dll"
     Runtime="NET"
   />
-  <UsingTask
-    TaskName="IceRpc.Protobuf.Tools.BuildTelemetryTask"
-    TaskFactory="$(IceRpcProtobufToolsTaskFactory)"
-    AssemblyFile="$(IceRpcProtobufToolsTaskAssembliesPath)IceRpc.Protobuf.Tools.dll"
-    Runtime="NET"
-  />
   <ItemGroup Condition="'$(IceRpcProtobufToolsSourceBuild)' == 'true'">
     <!-- Add a reference to the Tools project to ensure it's built before we use its tasks -->
     <ProjectReference Include="$(MSBuildThisFileDirectory)IceRpc.Protobuf.Tools.csproj" ReferenceOutputAssembly="false" />
@@ -69,6 +63,24 @@
       <Output ItemName="_ProtoFile" TaskParameter="ComputedSources" />
     </UpToDateCheckTask>
 
+    <PropertyGroup>
+      <_ProtocPluginScriptExtension Condition="$([MSBuild]::IsOSPlatform('Windows'))">.bat</_ProtocPluginScriptExtension>
+      <_ProtocPluginScriptExtension Condition="!$([MSBuild]::IsOSPlatform('Windows'))">.sh</_ProtocPluginScriptExtension>
+    </PropertyGroup>
+
+    <ItemGroup>
+      <!-- Code-generating plug-ins; protoc runs once per ProtoFile to produce a dependency file per file. -->
+      <_ProtocCodegenPlugin Include="csharp" />
+      <_ProtocCodegenPlugin Include="icerpc-csharp">
+        <Path>$(IceRpcProtocGenPath)protoc-gen-icerpc-csharp$(_ProtocPluginScriptExtension)</Path>
+      </_ProtocCodegenPlugin>
+
+      <!-- Telemetry plug-in; runs once over all ProtoFile items so the upload reports the whole build. -->
+      <_ProtocTelemetryPlugin Include="icerpc-build-telemetry">
+        <Path>$(IceRpcProtocBuildTelemetryPath)protoc-gen-icerpc-build-telemetry$(_ProtocPluginScriptExtension)</Path>
+      </_ProtocTelemetryPlugin>
+    </ItemGroup>
+
     <!-- Compile the Proto files
       The search path determines where protoc compiler locates import files, we add:
       - $(IceRpcProtocPath) to import google well-known files from IceRpc.Protobuf.Tools.
@@ -81,13 +93,26 @@
       OutputDir="@(_ProtoFile->'%(OutputDir)')"
       SearchPath="@(ProtoSearchPath->'%(FullPath)');$(IceRpcProtocPath);$(MSBuildProjectDirectory)"
       ToolsPath="$(IceRpcProtocPath)$(IceRpcProtocPrefix)"
-      GenPath="$(IceRpcProtocGenPath)"
-      BuildTelemetryPath="$(IceRpcProtocBuildTelemetryPath)"
-      RunBuildTelemetry="$(IceRpcBuildTelemetry)"
+      Plugins="@(_ProtocCodegenPlugin)"
+      AdditionalOptions="--dependency_out=%(_ProtoFile.OutputDir)/%(_ProtoFile.OutputFileName).d"
       Sources="%(_ProtoFile.Identity)"
       Condition="'%(_ProtoFile.UpToDate)' != 'true'"
     />
 
+    <!--
+      Run the build-telemetry plug-in once over all ProtoFile items so it can compute a single per-build
+      compilation hash and file count from the descriptors, regardless of which files were up-to-date.
+    -->
+    <ProtocTask
+      WorkingDirectory="$(MSBuildProjectDirectory)"
+      OutputDir="$(IntermediateOutputPath)"
+      SearchPath="@(ProtoSearchPath->'%(FullPath)');$(IceRpcProtocPath);$(MSBuildProjectDirectory)"
+      ToolsPath="$(IceRpcProtocPath)$(IceRpcProtocPrefix)"
+      Plugins="@(_ProtocTelemetryPlugin)"
+      Sources="@(_ProtoFile)"
+      Condition="'$(IceRpcBuildTelemetry)' == 'true'"
+    />
+
     <!--
       Include all C# generated source items that have not been already included. We delay this until we are
       running the ProtoCompile target so that default includes are already processed.
diff --git a/src/IceRpc.Protobuf.Tools/ProtocTask.cs b/src/IceRpc.Protobuf.Tools/ProtocTask.cs
index a1b542c92d..a43a2c8b46 100644
--- a/src/IceRpc.Protobuf.Tools/ProtocTask.cs
+++ b/src/IceRpc.Protobuf.Tools/ProtocTask.cs
@@ -1,6 +1,5 @@
 // Copyright (c) ZeroC, Inc.
 
-using IceRpc.CaseConverter.Internal;
 using Microsoft.Build.Framework;
 using Microsoft.Build.Utilities;
 using System.Diagnostics;
@@ -12,15 +11,24 @@ namespace IceRpc.Protobuf.Tools;
 // Properties should not return arrays, disabled as this is standard for MSBuild tasks.
 #pragma warning disable CA1819
 
-/// <summary>A MSBuild task to generate code from Protobuf files using <c>protoc</c> C# built-in generator and
-/// <c>protoc-gen-icerpc-csharp</c> generator.</summary>
+/// <summary>An MSBuild task that runs <c>protoc</c> with a configurable set of plug-ins.</summary>
 public class ProtocTask : ToolTask
 {
-    /// <summary>Gets or sets the output directory for the generated code; corresponds to the
-    /// <c>--icerpc-csharp_out=</c> option of the <c>protoc</c> compiler.</summary>
+    /// <summary>Gets or sets additional options to pass verbatim to <c>protoc</c>.</summary>
+    public string[] AdditionalOptions { get; set; } = [];
+
+    /// <summary>Gets or sets the output directory shared by all configured plug-ins; corresponds to the
+    /// <c>--&lt;name&gt;_out=</c> option of the <c>protoc</c> compiler.</summary>
     [Required]
     public string OutputDir { get; set; } = "";
 
+    /// <summary>Gets or sets the protoc plug-ins to run. Each item's <c>Identity</c> is the plug-in name (for example
+    /// <c>csharp</c>, <c>icerpc-csharp</c>, <c>icerpc-build-telemetry</c>). The <c>Path</c> metadata, when not empty,
+    /// is the full path to the plug-in script and is passed via <c>--plugin protoc-gen-&lt;name&gt;=&lt;path&gt;</c>;
+    /// an empty <c>Path</c> indicates a protoc built-in such as <c>csharp</c>.</summary>
+    [Required]
+    public ITaskItem[] Plugins { get; set; } = [];
+
     /// <summary>Gets or sets the directories in which to search for imports, corresponds to <c>-I</c> protoc compiler
     /// option.</summary>
     public string[] SearchPath { get; set; } = [];
@@ -34,18 +42,6 @@ public class ProtocTask : ToolTask
     [Required]
     public string ToolsPath { get; set; } = "";
 
-    /// <summary>Gets or sets the directory containing the protoc-gen-icerpc-csharp scripts.</summary>
-    [Required]
-    public string GenPath { get; set; } = "";
-
-    /// <summary>Gets or sets the directory containing the protoc-gen-icerpc-build-telemetry scripts.</summary>
-    [Required]
-    public string BuildTelemetryPath { get; set; } = "";
-
-    /// <summary>Gets or sets a value indicating whether to run the build telemetry plug-in.</summary>
-    [Required]
-    public bool RunBuildTelemetry { get; set; }
-
     /// <summary>Gets or sets the working directory for executing the protoc compiler from.</summary>
     [Required]
     [System.Diagnostics.CodeAnalysis.SuppressMessage(
@@ -63,44 +59,31 @@ protected override string GenerateCommandLineCommands()
     {
         var builder = new CommandLineBuilder(false);
 
-        // Specify the full path to the protoc-gen-icerpc-csharp script.
-
-        string genScriptName =
-            RuntimeInformation.IsOSPlatform(OSPlatform.Windows) ?
-                "protoc-gen-icerpc-csharp.bat" : "protoc-gen-icerpc-csharp.sh";
-        builder.AppendSwitch("--plugin");
-        builder.AppendFileNameIfNotNull($"protoc-gen-icerpc-csharp={Path.Combine(GenPath, genScriptName)}");
+        // Register and enable each plug-in.
+        foreach (ITaskItem plugin in Plugins)
+        {
+            string name = plugin.ItemSpec;
+            string pluginPath = plugin.GetMetadata("Path");
 
-        // Add --csharp_out to generate Protobuf C# code
-        builder.AppendSwitch("--csharp_out");
-        builder.AppendFileNameIfNotNull(OutputDir);
+            if (!string.IsNullOrEmpty(pluginPath))
+            {
+                builder.AppendSwitch("--plugin");
+                builder.AppendFileNameIfNotNull($"protoc-gen-{name}={pluginPath}");
+            }
 
-        // Add --icerpc-csharp_out to generate IceRPC + Protobuf integration code
-        builder.AppendSwitch("--icerpc-csharp_out");
-        builder.AppendFileNameIfNotNull(OutputDir);
+            builder.AppendSwitch($"--{name}_out");
+            builder.AppendFileNameIfNotNull(OutputDir);
+        }
 
-        if (RunBuildTelemetry)
+        foreach (string option in AdditionalOptions)
         {
-            // Enable build telemetry
-            string buildTelemetryScriptName =
-                RuntimeInformation.IsOSPlatform(OSPlatform.Windows) ?
-                    "protoc-gen-icerpc-build-telemetry.bat" : "protoc-gen-icerpc-build-telemetry.sh";
-
-            // Specify the full path to the protoc-gen-icerpc-build-telemetry script.
-            builder.AppendSwitch("--plugin");
-            builder.AppendFileNameIfNotNull(
-                $"protoc-gen-icerpc-build-telemetry={Path.Combine(BuildTelemetryPath, buildTelemetryScriptName)}");
-
-            // Add --icerpc-build-telemetry_out to enable build telemetry, even though the build telemetry plug-in
-            // doesn't need to generate any output files.
-            builder.AppendSwitch("--icerpc-build-telemetry_out");
-            builder.AppendFileNameIfNotNull(OutputDir);
+            builder.AppendTextUnquoted(" ");
+            builder.AppendTextUnquoted(option);
         }
 
         var searchPath = new List<string>(SearchPath);
 
-        // Add the sources directories to the import search path
-        var computedSources = new List<ITaskItem>();
+        // Add the sources directories to the import search path.
         foreach (ITaskItem source in Sources)
         {
             string fullPath = source.GetMetadata("FullPath");
@@ -109,14 +92,8 @@ protected override string GenerateCommandLineCommands()
             {
                 searchPath.Add(directory);
             }
-
-            // Add dependency_out to generate dependency files
-            builder.AppendSwitch("--dependency_out");
-            builder.AppendFileNameIfNotNull(
-                Path.Combine(OutputDir, $"{source.GetMetadata("FileName").ToPascalCase()}.d"));
         }
 
-        // Add protoc searchPath paths
         foreach (string path in searchPath)
         {
             builder.AppendSwitch("-I");