cactuaroid / GrpcWpfSample

gRPC sample WPF/Console apps in C#

Overview

Chat server-client applications as a sample implementation using gRPC for .NET (Grpc.AspNetCore/Grpc.Net.Client) and gRPC for C# (Grpc.Core).

Client

Project	Type	Target	Used Package
GrpcChatSample.Client.ConsoleApp	Console app	.NET 6.0	Grpc.Core
GrpcChatSample.Client.Wpf	WPF app	.NET Framework 4.8	Grpc.Core
GrpcChatSample2.Client.ConsoleApp	Console app	.NET 6.0	Grpc.Net.Client
GrpcChatSample2.Client.Wpf	WPF app	.NET 6.0	Grpc.Net.Client

Server

Project	Type	Target	Used Package
GrpcChatSample.Server.ConsoleApp	Console app	.NET 6.0	Grpc.Core
GrpcChatSample.Server.Wpf	WPF app	.NET Framework 4.8	Grpc.Core
GrpcChatSample2.Server.ConsoleApp	Console app	.NET 6.0	Grpc.AspNetCore
GrpcChatSample2.Server.Wpf	WPF app	.NET 6.0	Grpc.AspNetCore

• These projects are not made from ASP.NET Core gRPC service project template, but adding gRPC service/client on console/WPF app project.
• .NET Framework apps are supported by Grpc.Core.
  • Limited support by Grpc.Net.Client but no sample in this repository.
• ASP.NET Core apps are supported by both, but Grpc.AspNetCore/Grpc.Net.Client is recommended.
• See https://grpc.io/blog/grpc-csharp-future/
• You cannot put proto file in WPF project. See grpc/grpc#20402

Implements

• Simple RPC: Client registers a message to server.
• Server-side streaming RPC: Server streams messages to clients.
• Interceptors: Client puts its ID for each calls. Server checks client IP address and ID for each calls.
• Request Header R/W: Client puts its ID on request header (metadata) of the call.

Read the official information

• https://grpc.io/docs/languages/csharp/
• https://grpc.io/docs/guides/
• https://docs.microsoft.com/ja-jp/aspnet/core/grpc/
• https://cloud.google.com/apis/design

RPC Service Definition (chat.proto)

service Chat {
  rpc Write(ChatLog) returns (google.protobuf.Empty) {}
  rpc Subscribe(google.protobuf.Empty) returns (stream ChatLog) {}
}

Architecture

DB is not implemented but on-memory List is used as a placeholder.

How to Run

1. Start a server.
2. Start client(s). You can start multiple clients.
   • For the console app, write a name and hit enter key first.
3. On client, write a message and hit enter key.
4. Your message will be registered on server, and you can see it on the client.

How to Enable SSL

grpc-dotnet

See these classes. Enable listenOptions.UseHttps() of server and locate .pfx file. Set var https = true of client.

• ChatGrpcServer.cs
• ChatServiceClient.cs

GrpcCore

See these classes. Locate required files and then change var secure = true; to enable SSL.

• ChatGrpcServer.cs
• ChatServiceClient.cs

File Name	Description
localhost_server.crt	Server's certificate
localhost_serverkey.pem	Private key of the server's certificate
localhost_client.crt	Client's certificate (optional)
localhost_clientkey.pem	Private key of the client's certificate (optional)

• All these files have to be PEM format without encryption.
• The server has to have the client's certificate or its CA certificate and vice versa. Here you can find an idea about this.
• The sample implementation includes client authentication as well. You can disable it then you don't need client's certificate and its private key.

Remarks

• You have to set "localhost" as Common Name (CN) of the certificate for your test on localhost.
• XCA is the one of the easy way to create the these files.