Improve compiler server/client logging

src/Compilers/Core/MSBuildTask/Directory.Build.props

@@ -47,6 +47,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)PropertyDictionary.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)RCWForCurrentContext.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)ShowMessageForImplicitlySkipAnalyzers.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)TaskCompilerServerLogger.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Utilities.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)ValidateBootstrap.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Vbc.cs" />

src/Compilers/Core/MSBuildTask/ManagedCompiler.cs

@@ -506,7 +506,8 @@ public string GeneratePathToTool()
 
         protected override int ExecuteTool(string pathToTool, string responseFileCommands, string commandLineCommands)
         {
-            using var logger = new CompilerServerLogger($"MSBuild {Process.GetCurrentProcess().Id}");
+            using var innerLogger = new CompilerServerLogger($"MSBuild {Process.GetCurrentProcess().Id}");
+            var logger = new TaskCompilerServerLogger(Log, innerLogger);
             return ExecuteTool(pathToTool, responseFileCommands, commandLineCommands, logger);
         }
 
@@ -818,7 +819,6 @@ private void LogCompilationMessage(ICompilerServerLogger logger, string requestI
             else
             {
                 logger.Log(message);
-                Log.LogMessage(message);
             }
         }
 

src/Compilers/Core/MSBuildTask/TaskCompilerServerLogger.cs

@@ -0,0 +1,28 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using Microsoft.Build.Utilities;
+using Microsoft.CodeAnalysis.CommandLine;
+
+namespace Microsoft.CodeAnalysis.BuildTasks;
+
+/// <summary>
+/// Logs to both the MSBuild task's output and the inner compiler server logger.
+/// </summary>
+internal sealed class TaskCompilerServerLogger(
+    TaskLoggingHelper taskLogger,
+    ICompilerServerLogger inner)
+    : ICompilerServerLogger
+{
+    private readonly TaskLoggingHelper _taskLogger = taskLogger;
+    private readonly ICompilerServerLogger _inner = inner;
+
+    public bool IsLogging => true;
+
+    public void Log(string message)
+    {
+        _inner.Log(message);
+        _taskLogger.LogMessage(message);
+    }
+}

src/Compilers/Server/VBCSCompiler/VBCSCompiler.cs

@@ -2,18 +2,18 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-using Microsoft.CodeAnalysis.CommandLine;
 using System;
 using System.Collections.Specialized;
-using System.IO;
+using System.Diagnostics;
+using Microsoft.CodeAnalysis.CommandLine;
 
 namespace Microsoft.CodeAnalysis.CompilerServer
 {
     internal static class VBCSCompiler
     {
         public static int Main(string[] args)
         {
-            using var logger = new CompilerServerLogger("VBCSCompiler");
+            using var logger = new CompilerServerLogger($"VBCSCompiler {Process.GetCurrentProcess().Id}");
 
             NameValueCollection appSettings;
             try

src/Compilers/Shared/BuildServerConnection.cs

@@ -460,6 +460,8 @@ internal static bool TryCreateServer(string clientDirectory, string pipeName, IC
                 return false;
             }
 
+            logger.Log("Attempting to create process '{0}' {1}", serverInfo.processFilePath, serverInfo.commandLineArguments);
+
             if (PlatformInformation.IsWindows)
             {
                 // As far as I can tell, there isn't a way to use the Process class to
@@ -476,8 +478,6 @@ internal static bool TryCreateServer(string clientDirectory, string pipeName, IC
 
                 PROCESS_INFORMATION processInfo;
 
-                logger.Log("Attempting to create process '{0}'", serverInfo.processFilePath);
-
                 var builder = new StringBuilder($@"""{serverInfo.processFilePath}"" {serverInfo.commandLineArguments}");
 
                 bool success = CreateProcess(
@@ -524,6 +524,7 @@ internal static bool TryCreateServer(string clientDirectory, string pipeName, IC
                     if (Process.Start(startInfo) is { } process)
                     {
                         processId = process.Id;
+                        logger.Log("Successfully created process with process id {0}", processId);
                         return true;
                     }
                     else

src/Compilers/Shared/CompilerServerLogger.cs

@@ -100,7 +100,6 @@ internal sealed class CompilerServerLogger : ICompilerServerLogger, IDisposable
     {
         // Environment variable, if set, to enable logging and set the file to log to.
         internal const string EnvironmentVariableName = "RoslynCommandLineLogFile";
-        internal const string LoggingPrefix = "---";
 
         private Stream? _loggingStream;
         private readonly string _identifier;
@@ -152,7 +151,7 @@ public void Log(string message)
             if (_loggingStream is object)
             {
                 var threadId = Environment.CurrentManagedThreadId;
-                var prefix = $"ID={_identifier} TID={threadId}: ";
+                var prefix = $"[{DateTimeOffset.Now:o}] ID={_identifier} TID={threadId}: ";
                 string output = prefix + message + Environment.NewLine;
                 byte[] bytes = Encoding.UTF8.GetBytes(output);