JSONRpc Client over websocket C#

Question

I need a JSON-Rpc client to communicate over websocket to the server. In particular, I need to create an interface and use methods to send JSON requests to the server.

Does someone know how to do that?

I found the StreamJsonRpc library, but it works over stream and not over websocket.

Can I get the stream from websocket connection and pas it to StreamJsonRpc?
Do you have other ideas?

score 3 · Accepted Answer · answered Jul 02 '18 at 09:53

You only need Json.net and WebSocket4Net.

You can see there.

using Newtonsoft.Json;
using Newtonsoft.Json.Linq;
using System;
using System.Security.Authentication;
using WebSocket4Net;

namespace LightStreamSample
{
    class WebSocket4NetSample
    {
        static void Main(string[] args)
        {
            var channelName = "[your websocket server channel name]";
            // note: reconnection handling needed.
            var websocket = new WebSocket("wss://[your web socket server websocket url]", sslProtocols: SslProtocols.Tls12);
            websocket.Opened += (sender, e) =>
            {
                websocket.Send(
                    JsonConvert.SerializeObject(
                        new
                        {
                            method = "subscribe",
                            @params = new { channel = channelName },
                            id = 123,
                        }
                    )
                );
            };
            websocket.MessageReceived += (sender, e) =>
            {
                dynamic data = JObject.Parse(e.Message);
                if (data.id == 123)
                {
                    Console.WriteLine("subscribed!");
                }
                if (data.@params != null)
                {
                    Console.WriteLine(data.@params.channel + " " + data.@params.message);
                }
            };

            websocket.Open();

            Console.ReadKey();
        }
    }
}

Thanks, i follow your suggestion to develop my application – Mattia Jul 03 '18 at 09:50 — Mattia, Jul 03 '18 at 09:50

score 1 · Answer 2 · answered Mar 28 '22 at 15:34

To update this post, it is now possible to pass the stream from the websocket using StreamJsonRpc.

Github websocket sample for .NetCore

 using (var jsonRpc = new JsonRpc(new WebSocketMessageHandler(socket)))
            {
                try
                {
                    jsonRpc.AddLocalRpcMethod("Tick", new Action<int>(tick => Console.WriteLine($"Tick {tick}!")));
                    jsonRpc.StartListening();
                    Console.WriteLine("JSON-RPC protocol over web socket established.");
                    int result = await jsonRpc.InvokeWithCancellationAsync<int>("Add", new object[] { 1, 2 }, cancellationToken);
                    Console.WriteLine($"JSON-RPC server says 1 + 2 = {result}");

                    // Request notifications from the server.
                    await jsonRpc.NotifyAsync("SendTicksAsync");

                    await jsonRpc.Completion.WithCancellation(cancellationToken);
                }
                catch (OperationCanceledException)
                {
                    // Closing is initiated by Ctrl+C on the client.
                    // Close the web socket gracefully -- before JsonRpc is disposed to avoid the socket going into an aborted state.
                    await socket.CloseAsync(WebSocketCloseStatus.NormalClosure, "Client closing", CancellationToken.None);
                    throw;
                }
            }

The .Net Framework implemenation is similar but slightly different

JSONRpc Client over websocket C#

2 Answers2