...
import (
    ...

    "github.com/gorilla/websocket"
    "github.com/leffss/gowebssh"
)
...
id := r.Header.Get("Sec-WebSocket-Key")
webssh := gowebssh.NewWebSSH()
webssh.SetTerm(gowebssh.TermLinux)
webssh.SetBuffSize(8192)
webssh.SetId(id)
webssh.SetConnTimeOut(15 * time.Second)
webssh.DisableSZ()
//webssh.DisableRZ()
...
upGrader := websocket.Upgrader{
    CheckOrigin: func(r *http.Request) bool {
        return true
    },
    //Subprotocols: []string{r.Header.Get("Sec-WebSocket-Protocol")},
    Subprotocols: []string{"webssh"},
    ReadBufferSize: 8192,
    WriteBufferSize: 8192,
}
ws, _ := upGrader.Upgrade(w, r, nil)
webssh.AddWebsocket(ws)

type messageType string

const (
	messageTypeAddr      = "addr"
	messageTypeTerm      = "term"
	messageTypeLogin     = "login"
	messageTypePassword  = "password"
	messageTypePublickey = "publickey"
	messageTypeStdin     = "stdin"
	messageTypeStdout    = "stdout"
	messageTypeStderr    = "stderr"
	messageTypeResize    = "resize"
	messageTypeIgnore    = "ignore"
	messageTypeConsole   = "console"
)

type message struct {
	Type messageType  `json:"type"`
	Data []byte       `json:"data,omitempty"`
	Cols int          `json:"cols,omitempty"`
	Rows int          `json:"rows,omitempty"`
}

function utf8_to_b64(rawString) {
  return btoa(unescape(encodeURIComponent(rawString)));
}

function b64_to_utf8(encodeString) {
  return decodeURIComponent(escape(atob(encodeString)));
}