Add target framework netstandard 2.0 so Auth0Net.DependencyInjection can be used in .NET Framework and .NET 5.0

src/Auth0Net.DependencyInjection/Auth0Extensions.cs

@@ -46,18 +46,18 @@ public static IHttpClientBuilder AddAuth0AuthenticationClientCore(this IServiceC
     /// <returns>An <see cref="IHttpClientBuilder" /> that can be used to configure the <see cref="HttpClientAuthenticationConnection"/>.</returns>
     public static IHttpClientBuilder AddAuth0AuthenticationClient(this IServiceCollection services, Action<Auth0Configuration> config)
     {
-        if(services.Any(x=> x.ServiceType == typeof(IAuthenticationApiClient)))
+        if (services.Any(x => x.ServiceType == typeof(IAuthenticationApiClient)))
             throw new InvalidOperationException("AuthenticationApiClient has already been registered!");
 
         services.AddOptions<Auth0Configuration>()
             .Configure(config)
             .Validate(x => !string.IsNullOrWhiteSpace(x.ClientId) && !string.IsNullOrWhiteSpace(x.Domain) && !string.IsNullOrWhiteSpace(x.ClientSecret),
                 "Auth0 Configuration cannot have empty values");
-        
+
         return services.AddAuth0AuthenticationClientInternal(true);
     }
-    
-    
+
+
     /// <summary>
     /// Adds a <see cref="AuthenticationApiClient" /> integrated with <see cref="IHttpClientBuilder" /> as well as the <see cref="IAuth0TokenCache" /> and related services to the <see cref="IServiceCollection" />.
     /// </summary>
@@ -69,14 +69,14 @@ public static IHttpClientBuilder AddAuth0AuthenticationClient(this IServiceColle
     /// <returns>An <see cref="IHttpClientBuilder" /> that can be used to configure the <see cref="HttpClientAuthenticationConnection"/>.</returns>
     public static IHttpClientBuilder AddAuth0AuthenticationClient(this IServiceCollection services, Action<Auth0Configuration, IServiceProvider> config)
     {
-        if(services.Any(x=> x.ServiceType == typeof(IAuthenticationApiClient)))
+        if (services.Any(x => x.ServiceType == typeof(IAuthenticationApiClient)))
             throw new InvalidOperationException("AuthenticationApiClient has already been registered!");
 
         services.AddOptions<Auth0Configuration>()
             .Configure(config)
             .Validate(x => !string.IsNullOrWhiteSpace(x.ClientId) && !string.IsNullOrWhiteSpace(x.Domain) && !string.IsNullOrWhiteSpace(x.ClientSecret),
                 "Auth0 Configuration cannot have empty values");
-        
+
         return services.AddAuth0AuthenticationClientInternal(true);
     }
 
@@ -91,15 +91,17 @@ private static IHttpClientBuilder AddAuth0AuthenticationClientInternal(this ISer
 
         services.AddSingleton<IAuthenticationApiClient, InjectableAuthenticationApiClient>();
         return services.AddHttpClient<IAuthenticationConnection, HttpClientAuthenticationConnection>()
-            .ConfigurePrimaryHttpMessageHandler(() => 
+#if !NETSTANDARD2_0
+            .ConfigurePrimaryHttpMessageHandler(() =>
                 new SocketsHttpHandler()
                 {
                     PooledConnectionLifetime = TimeSpan.FromMinutes(2)
                 })
+#endif
             .SetHandlerLifetime(Timeout.InfiniteTimeSpan);
     }
-    
-    
+
+
 
     /// <summary>
     /// Adds a <see cref="ManagementApiClient" /> integrated with <see cref="IHttpClientBuilder" /> to the <see cref="IServiceCollection" />.
@@ -114,11 +116,13 @@ public static IHttpClientBuilder AddAuth0ManagementClient(this IServiceCollectio
         services.AddSingleton<IManagementApiClient, InjectableManagementApiClient>();
 
         return services.AddHttpClient<IManagementConnection, HttpClientManagementConnection>()
-            .ConfigurePrimaryHttpMessageHandler(() => 
+#if !NETSTANDARD2_0
+            .ConfigurePrimaryHttpMessageHandler(() =>
                 new SocketsHttpHandler()
                 {
                     PooledConnectionLifetime = TimeSpan.FromMinutes(2)
                 })
+#endif
             .SetHandlerLifetime(Timeout.InfiniteTimeSpan);
     }
 
@@ -136,7 +140,7 @@ public static IHttpClientBuilder AddAccessToken(this IHttpClientBuilder builder,
         if (c.AudienceResolver is null && string.IsNullOrWhiteSpace(c.Audience))
             throw new ArgumentException("Audience or AudienceResolver must be set");
 
-        return builder.AddHttpMessageHandler(provider => 
+        return builder.AddHttpMessageHandler(provider =>
             new Auth0TokenHandler(provider.GetRequiredService<IAuth0TokenCache>(), c));
     }
 

src/Auth0Net.DependencyInjection/Auth0Net.DependencyInjection.csproj

@@ -1,13 +1,14 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net6.0;net7.0;net8.0</TargetFrameworks>
+    <TargetFrameworks>netstandard2.0;net6.0;net7.0;net8.0</TargetFrameworks>
     <GenerateDocumentationFile>true</GenerateDocumentationFile>
     <Nullable>enable</Nullable>
     <ImplicitUsings>enable</ImplicitUsings>
-    <Version>3.1.0</Version>
+    <Version>3.1.1</Version>
     <Authors>Hawxy</Authors>
     <Description>Dependency Injection, HttpClientFactory &amp; ASP.NET Core extensions for Auth0.NET</Description>
+		<LangVersion>latest</LangVersion>
     <PackageRequireLicenseAcceptance>true</PackageRequireLicenseAcceptance>
     <Copyright>Hawxy 2020-2023</Copyright>
     <PackageIcon>icon.png</PackageIcon>
@@ -26,6 +27,12 @@
     <PackageReference Include="ZiggyCreatures.FusionCache" Version="0.24.0" />
   </ItemGroup>
 
+	<ItemGroup Condition=" '$(TargetFramework)' == 'netstandard2.0' ">
+		<PackageReference Include="Microsoft.Extensions.Caching.Memory" Version="6.0.0" />
+		<PackageReference Include="Microsoft.Extensions.Configuration.Abstractions" Version="6.0.0" />
+		<PackageReference Include="Microsoft.Extensions.Http" Version="6.0.0" />
+	</ItemGroup>
+
   <ItemGroup Condition=" '$(TargetFramework)' == 'net6.0' ">
     <PackageReference Include="Microsoft.Extensions.Caching.Memory" Version="6.0.0" />
     <PackageReference Include="Microsoft.Extensions.Http" Version="6.0.0" />

tests/Auth0Net.DependencyInjection.Tests/Auth0Net.DependencyInjection.Tests.csproj

@@ -1,8 +1,9 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net6.0;net7.0;net8.0</TargetFrameworks>
     <IsPackable>false</IsPackable>
+    <TargetFrameworks>net48;net6.0;net7.0;net8.0</TargetFrameworks>
+		<LangVersion>latest</LangVersion>
   </PropertyGroup>
 
   <ItemGroup>

tests/Auth0Net.DependencyInjection.Tests/System.Runtime.CompilerServices/IsExternalInit.cs

@@ -0,0 +1,27 @@
+// Original source code copied from
+// https://github.com/dotnet/runtime/blob/main/src/libraries/System.Private.CoreLib/src/System/Runtime/CompilerServices/IsExternalInit.cs
+// - Steven Volckaert, 19 OCT 2023.
+
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+namespace System.Runtime.CompilerServices;
+
+#if NETSTANDARD2_0 ||  NETCOREAPP2_0 ||  NETCOREAPP2_1 ||  NETCOREAPP2_2 || NETCOREAPP3_0 || NETCOREAPP3_1 || NET45 || NET451 || NET452 || NET46 || NET461 || NET462 || NET47 || NET471 || NET472 || NET48 || NET481
+
+using System.ComponentModel;
+
+/// <summary>
+/// Reserved to be used by the compiler for tracking metadata.
+/// This class should not be used by developers in source code.
+/// </summary>
+[EditorBrowsable(EditorBrowsableState.Never)]
+#if SYSTEM_PRIVATE_CORELIB
+public
+#else
+internal
+#endif
+static class IsExternalInit
+{
+}
+#endif