enable netstandard2.0 (#60)

Author: yyyu-google

sdks/dotnet/BinaryInstaller.cs

@@ -154,7 +154,11 @@ private static async Task<string> ComputeSha256Async(string filePath)
     {
       using var stream = File.OpenRead(filePath);
       using var sha = SHA256.Create();
+#if NETSTANDARD2_0
+      var hash = sha.ComputeHash(stream);
+#else
       var hash = await sha.ComputeHashAsync(stream);
+#endif
       return BitConverter.ToString(hash).Replace("-", string.Empty).ToLowerInvariant();
     }
 
@@ -163,7 +167,15 @@ private static void ExtractArchive(string archivePath, string archiveExt, string
       Console.WriteLine($"[TestServerSDK] Extracting {archivePath} to {destDir}...");
       if (archiveExt == ".zip")
       {
+#if NETSTANDARD2_0
+        if (Directory.Exists(destDir))
+        {
+          Directory.Delete(destDir, true);
+        }
+        System.IO.Compression.ZipFile.ExtractToDirectory(archivePath, destDir);
+#else
         System.IO.Compression.ZipFile.ExtractToDirectory(archivePath, destDir, true);
+#endif
       }
       else
       {

sdks/dotnet/TestServerSdk.csproj

@@ -1,11 +1,11 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFrameworks>net6.0;net8.0</TargetFrameworks>
+    <TargetFrameworks>netstandard2.0;net6.0;net8.0</TargetFrameworks>
     <LangVersion>latest</LangVersion>
     <Nullable>enable</Nullable>
     <ImplicitUsings>enable</ImplicitUsings>
 
-    <PackageVersion>0.1.5</PackageVersion>
+    <PackageVersion>0.1.6</PackageVersion>
     <Authors>Google LLC</Authors>
     <Description>A .NET SDK to manage the test-server process for integration testing.</Description>
     <PackageProjectUrl>https://github.com/google/test-server</PackageProjectUrl>
@@ -21,6 +21,7 @@
   <ItemGroup>
     <PackageReference Include="YamlDotNet" Version="12.0.2" />
     <PackageReference Include="SharpCompress" Version="0.29.0" />
+    <PackageReference Include="System.Text.Json" Version="10.0.0" />
   </ItemGroup>
   <ItemGroup>
     <!-- ADD this to embed the file directly into the DLL -->