thread safe

Author: suhsteve

src/csharp/Extensions/Microsoft.Spark.Extensions.DotNet.Interactive/PackageHelper.cs

@@ -2,8 +2,10 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.IO;
+using System.Threading;
 using Microsoft.DotNet.Interactive.Utility;
 using Microsoft.Spark.Utils;
 
@@ -12,13 +14,13 @@ namespace Microsoft.Spark.Extensions.DotNet.Interactive
     internal class PackageHelper
     {
         private readonly PackageRestoreContextWrapper _packageRestoreContextWrapper;
-        private readonly HashSet<string> _filesCopied;
-        private ulong _metadataCounter;
+        private readonly ConcurrentDictionary<string, byte> _filesCopied;
+        private long _metadataCounter;
 
         internal PackageHelper(PackageRestoreContextWrapper packageRestoreContextWrapper)
         {
             _packageRestoreContextWrapper = packageRestoreContextWrapper;
-            _filesCopied = new HashSet<string>();
+            _filesCopied = new ConcurrentDictionary<string, byte>();
             _metadataCounter = 0;
         }
 
@@ -89,7 +91,8 @@ internal IEnumerable<string> GetFiles(string writePath)
                 var metadataPath =
                     Path.Combine(
                         writePath,
-                        DependencyProviderUtils.CreateFileName(++_metadataCounter));
+                        DependencyProviderUtils.CreateFileName(
+                            Interlocked.Increment(ref _metadataCounter)));
                 new DependencyProviderUtils.Metadata
                 {
                     AssemblyProbingPaths = assemblyProbingPaths.ToArray(),
@@ -117,7 +120,7 @@ private IEnumerable<ResolvedNuGetPackage> GetNewPackages()
 
                 foreach (FileInfo file in files)
                 {
-                    if (_filesCopied.Add(file.Name))
+                    if (_filesCopied.TryAdd(file.Name, 1))
                     {
                         yield return new ResolvedNuGetPackage
                         {

src/csharp/Microsoft.Spark.UnitTest/DependencyProviderUtilsTests.cs

@@ -131,7 +131,7 @@ public void TestMetadataSerDe()
         public void TestFileNames()
         {
             using var tempDir = new TemporaryDirectory();
-            foreach (ulong num in Enumerable.Range(0, 3).Select(x => System.Math.Pow(10, x)))
+            foreach (long num in Enumerable.Range(0, 3).Select(x => System.Math.Pow(10, x)))
             {
                 string filePath =
                     Path.Combine(tempDir.Path, DependencyProviderUtils.CreateFileName(num));
@@ -140,9 +140,9 @@ public void TestFileNames()
 
             var expectedFiles = new string[] 
             {
-                "dependencyProviderMetadata_00000000000000000001",
-                "dependencyProviderMetadata_00000000000000000010",
-                "dependencyProviderMetadata_00000000000000000100",
+                "dependencyProviderMetadata_0000000000000000001",
+                "dependencyProviderMetadata_0000000000000000010",
+                "dependencyProviderMetadata_0000000000000000100",
             };
             IOrderedEnumerable<string> actualFiles = DependencyProviderUtils
                 .GetMetadataFiles(tempDir.Path)

src/csharp/Microsoft.Spark.Worker/Utils/AssemblyLoaderHelper.cs

@@ -49,7 +49,7 @@ static AssemblyLoaderHelper()
         /// These files include:
         /// - "{packagename}.{version}.nupkg"
         ///   The nuget packages
-        /// - <see cref="DependencyProviderUtils.CreateFileName(ulong)"/>
+        /// - <see cref="DependencyProviderUtils.CreateFileName(long)"/>
         ///   Serialized <see cref="DependencyProviderUtils.Metadata"/> object.
         ///
         /// On the Worker, in order to resolve the nuget dependencies referenced by

src/csharp/Microsoft.Spark/Utils/DependencyProviderUtils.cs

@@ -19,12 +19,12 @@ internal static string[] GetMetadataFiles(string path) =>
         // function.
         // 
         // number => filename
-        // 0      => dependencyProviderMetadata_00000000000000000000
-        // 1      => dependencyProviderMetadata_00000000000000000001
+        // 0      => dependencyProviderMetadata_0000000000000000000
+        // 1      => dependencyProviderMetadata_0000000000000000001
         // ...
-        // 20     => dependencyProviderMetadata_00000000000000000020
-        internal static string CreateFileName(ulong number) =>
-            s_filePattern.Replace("*", $"{number:D20}");
+        // 20     => dependencyProviderMetadata_0000000000000000020
+        internal static string CreateFileName(long number) =>
+            s_filePattern.Replace("*", $"{number:D19}");
 
         [Serializable]
         internal class NuGetMetadata