Di manakah pelayan jsonrpc2 Golang mendengar?

package main

import (
    "context"
    "fmt"
    "os"
    "sync"

    "github.com/sourcegraph/jsonrpc2"
)

type lspserver struct {
    // the symmetric connection
    conn jsonrpc2.conn

    // check if the connection is available
    connmutex sync.mutex

    // shutdown
    shutdown bool
}

func newlspserver() *lspserver {
    return &lspserver{}
}

func (s *lspserver) initialize(ctx context.context) error {
    // to implement
    return nil
}

func (s *lspserver) handle(context.context, *jsonrpc2.conn, *jsonrpc2.request) (result interface{}, err error) {
    fmt.println("handling request...")
    // to implement
    return nil, nil
}

func (s *lspserver) serve(ctx context.context) {
    fmt.println("starting lsp server...")
    // what port is this server listening on?
    // it is listening on port 4389

    // create a new jsonrpc2 stream server
    handler := jsonrpc2.handlerwitherror(s.handle)

    // create a new jsonrpc2 stream server
    <-jsonrpc2.newconn(
        context.background(),
        jsonrpc2.newbufferedstream(os.stdin, jsonrpc2.vscodeobjectcodec{}),
        handler).disconnectnotify()
}

func main() {

    // create a new lsp server
    server := newlspserver()
    server.serve(context.background())

}

import json
import requests

def rpc_call(url, method, args):
    headers = {'content-type': 'application/json'}
    payload = {
        "method": method,
        "params": [args],
        "jsonrpc": "2.0",
        "id": 1,
    }
    response = requests.post(url, data=json.dumps(payload), headers=headers).json()
    return response['result']

url = 'http://localhost:4389/'

emailArgs = {'To': '[email protected]','Subject': 'Hello', 'Content': 'Hi!!!'}
smsArgs = {'Number': '381641234567', 'Content': 'Sms!!!'}
print(rpc_call(url, 'email.SendEmail', emailArgs))
print(rpc_call(url, 'sms.SendSMS', smsArgs))

handlerwitherror(s.handle)

    // create a new jsonrpc2 stream server
    <-jsonrpc2.newconn(
        context.background(),
        jsonrpc2.newbufferedstream(os.stdin, jsonrpc2.vscodeobjectcodec{}),
        handler).disconnectnotify()
}

package main

import (
    "context"
    "net"
    "log"
    "sync"

    "github.com/sourcegraph/jsonrpc2"
)

type LSPServer struct {
    // The symmetric connection
    conn jsonrpc2.Conn

    // Check if the connection is available
    connMutex sync.Mutex

    // shutdown
    shutdown bool
}

func NewLSPServer() *LSPServer {
    return &LSPServer{}
}

func (s *LSPServer) Initialize(ctx context.Context) error {
    // Initialize here if needed
    return nil
}

func (s *LSPServer) Handle(context.Context, *jsonrpc2.Conn, *jsonrpc2.Request) (result interface{}, err error) {
    fmt.Println("Handling request...")
    // Handle something
    return nil, nil
}

func (s *LSPServer) Serve(ctx context.Context) {
    fmt.Println("Starting LSP server...")
    
    // Listen on TCP port 4389 on all available unicast and
    // anycast IP addresses of the local system.
    l, err := net.Listen("tcp", "localhost:4389")
    if err != nil {
        log.Fatal(err)
    }
    defer l.Close()

    for {
        // Wait for a connection.
        conn, err := l.Accept()
        if err != nil {
            log.Fatal(err)
        }

        // Handle the connection in a new goroutine.
        go func(c net.Conn) {
            // Create a new jsonrpc2 stream server
            handler := jsonrpc2.HandlerWithError(s.Handle)
            <-jsonrpc2.NewConn(
                ctx,
                jsonrpc2.NewBufferedStream(c, jsonrpc2.VSCodeObjectCodec{}),
                handler).DisconnectNotify()
            c.Close()
        }(conn)
    }
}

func main() {
    // Create a new LSP server
    server := NewLSPServer()
    go server.Serve(context.Background()) // run Serve in a separate goroutine
    select {} // wait forever
}