Quick fixes: Make `dotnet-getdocument` more reliable (#8716)

- use `WaitAny(...)` in inside man
- call `Process.WaitForExit()` twice
- `Flush()` all output `FileStream`s before disposal
- catch `UnauthorizedAccessException` when calling `File.Delete(...)` in case file's in use
- add `/nr:false` to `dotnet msbuild` command line

src/GetDocumentInsider/Commands/GetDocumentCommandWorker.cs

@@ -109,8 +109,8 @@ namespace Microsoft.Extensions.ApiDescription.Tool.Commands
                         return false;
                     }
 
-                    var finished = Task.WhenAny(resultTask, Task.Delay(TimeSpan.FromMinutes(1)));
-                    if (!ReferenceEquals(resultTask, finished))
+                    var finishedIndex = Task.WaitAny(resultTask, Task.Delay(TimeSpan.FromMinutes(1)));
+                    if (finishedIndex != 0)
                     {
                         Reporter.WriteWarning(Resources.FormatMethodTimedOut(methodName, serviceName, 1));
                         return false;
@@ -121,6 +121,8 @@ namespace Microsoft.Extensions.ApiDescription.Tool.Commands
                     using (var outStream = File.Create(context.OutputPath))
                     {
                         stream.CopyTo(outStream);
+
+                        outStream.Flush();
                     }
                 }
 

src/Microsoft.Extensions.ApiDescription.Design/DownloadFile.cs

@@ -177,6 +177,8 @@ namespace Microsoft.Extensions.ApiDescription.Tasks
                             using (var outStream = File.Create(destinationPath))
                             {
                                 await responseStream.CopyToAsync(outStream);
+
+                                await outStream.FlushAsync();
                             }
                         }
                     }

src/dotnet-getdocument/Commands/InvokeCommand.cs

@@ -186,8 +186,22 @@ namespace Microsoft.Extensions.ApiDescription.Tool.Commands
             {
                 if (cleanupExecutable && !string.IsNullOrEmpty(executable))
                 {
-                    File.Delete(executable);
-                    File.Delete(executable + ".config");
+                    // Ignore errors about in-use files. Should still be marked for delete after process cleanup.
+                    try
+                    {
+                        File.Delete(executable);
+                    }
+                    catch (UnauthorizedAccessException)
+                    {
+                    }
+
+                    try
+                    {
+                        File.Delete(executable + ".config");
+                    }
+                    catch (UnauthorizedAccessException)
+                    {
+                    }
                 }
             }
         }

src/dotnet-getdocument/Exe.cs

@@ -1,6 +1,7 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
+using System;
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Text;
@@ -31,20 +32,32 @@ namespace Microsoft.Extensions.ApiDescription.Tool
                 startInfo.WorkingDirectory = workingDirectory;
             }
 
-            var process = Process.Start(startInfo);
-
-            if (interceptOutput)
+            using (var process = Process.Start(startInfo))
             {
-                string line;
-                while ((line = process.StandardOutput.ReadLine()) != null)
+                if (interceptOutput)
                 {
-                    Reporter.WriteVerbose(line);
+                    string line;
+                    while ((line = process.StandardOutput.ReadLine()) != null)
+                    {
+                        Reporter.WriteVerbose(line);
+                    }
                 }
+
+                // Follow precedent set in Razor integration tests and ensure process events and output are complete.
+                // https://github.com/aspnet/Razor/blob/d719920fdcc7d1db3a6f74cd5404d66fa098f057/test/Microsoft.NET.Sdk.Razor.Test/IntegrationTests/MSBuildProcessManager.cs#L91-L102
+                // Timeout is double how long the inside man waits for the IDocumentProcessor to wrap up.
+                if (!process.WaitForExit((int)(TimeSpan.FromMinutes(2).TotalMilliseconds)))
+                {
+                    process.Kill();
+
+                    // Should be unreachable in almost every case.
+                    throw new TimeoutException($"Process {executable} timed out after 2 minutes.");
+                }
+
+                process.WaitForExit();
+
+                return process.ExitCode;
             }
-
-            process.WaitForExit();
-
-            return process.ExitCode;
         }
 
         private static string ToArguments(IReadOnlyList<string> args)

src/dotnet-getdocument/Project.cs

@@ -89,6 +89,8 @@ namespace Microsoft.Extensions.ApiDescription.Tool
                     // NB: Copy always in case it changes
                     Reporter.WriteVerbose(Resources.FormatWritingFile(targetsPath));
                     input.CopyTo(output);
+
+                    output.Flush();
                 }
             }
 
@@ -102,6 +104,7 @@ namespace Microsoft.Extensions.ApiDescription.Tool
                     "/target:WriteServiceProjectReferenceMetadata",
                     "/verbosity:quiet",
                     "/nologo",
+                    "/nodeReuse:false",
                     $"/property:ServiceProjectReferenceMetadataPath={metadataPath}",
                     projectFile,
                 };
@@ -134,8 +137,22 @@ namespace Microsoft.Extensions.ApiDescription.Tool
             }
             finally
             {
-                File.Delete(metadataPath);
-                File.Delete(targetsPath);
+                // Ignore errors about in-use files. Should still be marked for delete after process cleanup.
+                try
+                {
+                    File.Delete(metadataPath);
+                }
+                catch (UnauthorizedAccessException)
+                {
+                }
+
+                try
+                {
+                    File.Delete(targetsPath);
+                }
+                catch (UnauthorizedAccessException)
+                {
+                }
             }
 
             var project = new Project