Grpc.Net.Client >= 2.50.0 does not work on Android with grpc-web

[cupsos]

Related: #1927
Might be related: dotnet/runtime#45741

Grpc.Net.Client v2.49.0 + GrpcWebHandler(new HttpClientHandler()) works but Grpc.Net.Client v2.50.0 doesn't.

I think my android device cannot use SocketsHttpHandler because await new HttpClient(new SocketsHttpHandler()).GetAsync("https://aka.ms") throws an exception.

What are options for android device that cannot use SocketsHttpHandler?

What I tried

Grpc.Net.Client	GrpcChannelOptions.HttpHandler	UseNativeHttpHandler	Result
v2.49.0	GrpcWebHandler(new HttpClientHandler())	not set	✅ work
v2.49.0	GrpcWebHandler(new HttpClientHandler())	false	❌ SslException from gRPC call
v2.49.0	GrpcWebHandler(new SocketsHttpHandler())	not set	❌ SslException from gRPC call
v2.51.0	GrpcWebHandler(new HttpClientHandler())	not set	❌ InvalidOperationException from channel create
v2.51.0	GrpcWebHandler(new HttpClientHandler())	false	❌ SslException from gRPC call
v2.51.0	GrpcWebHandler(new SocketsHttpHandler())	not set	❌ SslException from gRPC call

Environment

• SDK: 7.0.102
• TFM: net7.0-android
• UI: MAUI Blazor
• OS: Android 7.1.2

Exception from GrpcChannel.ForAddress on Grpc.Net.Client >= 2.50.0

System.InvalidOperationException: The channel configuration isn't valid on Android devices. The channel is configured to use HttpClientHandler and Android's native HTTP/2 library. gRPC isn't fully supported by Android's native HTTP/2 library and it can cause runtime errors. To fix this problem, either configure the channel to use SocketsHttpHandler, or add <UseNativeHttpHandler>false</UseNativeHttpHandler> to the app's project file. For more information, see https://aka.ms/aspnet/grpc/android.
   at Grpc.Net.Client.GrpcChannel.CreateInternalHttpInvoker(HttpMessageHandler handler) in /_/src/Grpc.Net.Client/GrpcChannel.cs:line 402
   at Grpc.Net.Client.GrpcChannel..ctor(Uri address, GrpcChannelOptions channelOptions) in /_/src/Grpc.Net.Client/GrpcChannel.cs:line 155
   at Grpc.Net.Client.GrpcChannel.ForAddress(Uri address, GrpcChannelOptions channelOptions) in /_/src/Grpc.Net.Client/GrpcChannel.cs:line 607
   at Grpc.Net.Client.GrpcChannel.ForAddress(String address, GrpcChannelOptions channelOptions) in /_/src/Grpc.Net.Client/GrpcChannel.cs:line 570

Exception from gRPC call when using SocketsHttpHandler

Grpc.Core.RpcException: Status(StatusCode="Internal", Detail="Error starting gRPC call. HttpRequestException: The SSL connection could not be established, see inner exception. AuthenticationException: Authentication failed, see inner exception. SslException: Exception of type 'Interop+AndroidCrypto+SslException' was thrown.", DebugException="System.Net.Http.HttpRequestException: The SSL connection could not be established, see inner exception.
 ---> System.Security.Authentication.AuthenticationException: Authentication failed, see inner exception.
 ---> Interop+AndroidCrypto+SslException: Exception of type 'Interop+AndroidCrypto+SslException' was thrown.
   --- End of inner exception stack trace ---
   at System.Net.Security.SslStream.<ForceAuthenticationAsync>d__146`1[[System.Net.Security.AsyncReadWriteAdapter, System.Net.Security, Version=7.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a]].MoveNext()
   at System.Net.Http.ConnectHelper.EstablishSslConnectionAsync(SslClientAuthenticationOptions sslOptions, HttpRequestMessage request, Boolean async, Stream stream, CancellationToken cancellationToken)
   --- End of inner exception stack trace ---
   at System.Net.Http.ConnectHelper.EstablishSslConnectionAsync(SslClientAuthenticationOptions sslOptions, HttpRequestMessage request, Boolean async, Stream stream, CancellationToken cancellationToken)
   at System.Net.Http.HttpConnectionPool.ConnectAsync(HttpRequestMessage request, Boolean async, CancellationToken cancellationToken)
   at System.Net.Http.HttpConnectionPool.AddHttp2ConnectionAsync(QueueItem queueItem)
   at System.Threading.Tasks.TaskCompletionSourceWithCancellation`1.<WaitWithCancellationAsync>d__1[[System.Net.Http.Http2Connection, System.Net.Http, Version=7.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a]].MoveNext()
   at System.Net.Http.HttpConnectionPool.HttpConnectionWaiter`1.<WaitForConnectionAsync>d__5[[System.Net.Http.Http2Connection, System.Net.Http, Version=7.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a]].MoveNext()
   at System.Net.Http.HttpConnectionPool.SendWithVersionDetectionAndRetryAsync(HttpRequestMessage request, Boolean async, Boolean doRequestAuth, CancellationToken cancellationToken)
   at System.Net.Http.RedirectHandler.SendAsync(HttpRequestMessage request, Boolean async, CancellationToken cancellationToken)
   at Grpc.Net.Client.Web.GrpcWebHandler.SendAsyncCore(HttpRequestMessage request, CancellationToken cancellationToken) in /_/src/Grpc.Net.Client.Web/GrpcWebHandler.cs:line 166
   at Grpc.Net.Client.Balancer.Internal.BalancerHttpHandler.SendAsync(HttpRequestMessage request, CancellationToken cancellationToken) in /_/src/Grpc.Net.Client/Balancer/Internal/BalancerHttpHandler.cs:line 156
   at Grpc.Net.Client.Internal.GrpcCall`2.<RunCall>d__73.MoveNext() in /_/src/Grpc.Net.Client/Internal/GrpcCall.cs:line 493")

[cupsos]

I don't know why I didn't open it as bug or request template...
Close this, I will make a new issue again.

[cupsos]

I just figure out how to avoid this.

If you cannot use SocketsHttpHandler, try GrpcChannelOptions.HttpClient not GrpcChannelOptions.HttpHandler.

GrpcChannel.ForAddress(setting.Address, new GrpcChannelOptions
{
    // HttpHandler = new GrpcWebHandler(new HttpClientHandler()), // this will throw exception
    HttpClient = new HttpClient(new GrpcWebHandler(new HttpClientHandler())),
});

[JamesNK]

Fix this in GrpcChannel: #2020