Creating LSP (Language Server Protocol) for multiple clients using RPC - visual-studio-code

Question

I am trying to create a custom LSP.
My goal is to create one language server for both monaco editor (on web) and vscode extension.
Currently I use Node/IPC to connect the vscode-extension with the server.
and ws-jsonrpc to connect monaco editor with the server.
quoting from this article Extending a client with the language server protocol
:
There are multiple ways to use JSON-RPC, but you see these two ways in
most implementations:
Communication is done via the standard input / output, i.e., the command line interface
Communication is performed via TCP/IP, i.e., network messages similar to HTTP
I should be able to use JSON-RPC for both communication (internal communication between processes which is the vscode-extesion in my case , and external communication which is monaco-editor in my case)
Here is how I am launching the server for the moment:
For IPC communication:
const languageServer = new LanguageServer(createConnection(ProposedFeatures.all));
languageServer.start();
For WebSocket RPC:
import * as express from "express";
import * as ws from "ws";
import * as rpc from "vscode-ws-jsonrpc";
import * as url from "url";
import * as http from "http";
import * as net from "net";
const app = express();
const server = app.listen(3000);
const wss = new ws.Server({
noServer: true,
perMessageDeflate: false
});
function launch(socket : rpc.IWebSocket ){
const reader = new rpc.WebSocketMessageReader(socket);
const writer = new rpc.WebSocketMessageWriter(socket);
const languageServer = new LanguageServer(createConnection(reader, writer));
languageServer.start();
}
server.on('upgrade', (request: http.IncomingMessage, socket: net.Socket, head: Buffer) => {
const pathname = request.url ? url.parse(request.url).pathname : undefined;
console.log("server on upgrade ", pathname);
if (pathname === '/sampleServer') {
wss.handleUpgrade(request, socket, head, (webSocket: any) => {
const socket: rpc.IWebSocket = {
send: (content: any) => webSocket.send(content, (error: any) => {
if (error) {
throw error;
}
}),
onMessage: (cb: any) => webSocket.on('message', cb),
onError: (cb: any) => webSocket.on('error', cb),
onClose: (cb: any) => webSocket.on('close', cb),
dispose: () => webSocket.close()
};
// launch the server when the web socket is opened
if (webSocket.readyState === webSocket.OPEN) {
launch(socket);
} else {
webSocket.on('open', () => {
launch(socket);
});
}
});
}
})

Answer 1

The server that you are using should not operate with multiple clients using it at the same time. It even says: "the protocol currently assumes that one server serves one tool.". Also, maybe read this article about your topic. **https://code.visualstudio.com/api/language-extensions/language-server-extension-guide **