wsep

wsep is a high performance, web socket command execution protocol. It can be thought of as SSH without encryption.

It's useful in cases where you want to provide a command exec interface into a remote environment. It's implemented with WebSocket so it may be used directly by a browser frontend. Its symmetric design satisfies wsep.Execer for local and remote execution.

Examples

Error handling is omitted for brevity.

Client

conn, _, _ := websocket.Dial(ctx, "ws://remote.exec.addr", nil)
defer conn.Close(websocket.StatusAbnormalClosure, "terminate process")

execer := wsep.RemoteExecer(conn)
process, _ := execer.Start(ctx, wsep.Command{
  Command: "cat",
  Args:    []string{"go.mod"},
  Stdin:   false,
})

go io.Copy(os.Stderr, process.Stderr())
go io.Copy(os.Stdout, process.Stdout())

process.Wait()
conn.Close(websocket.StatusNormalClosure, "normal closure")

Server

func (s server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
  conn, _ := websocket.Accept(w, r, nil)

  wsep.Serve(r.Context(), conn, wsep.LocalExecer{})

  ws.Close(websocket.StatusNormalClosure, "normal closure")
}

Development / Testing

Start a local executor:

go run ./dev/server

Start a client:

go run ./dev/client tty bash
go run ./dev/client notty ls

Local performance cost

Local sh through a local wsep connection

$ head -c 100000000 /dev/urandom > /tmp/random; cat /tmp/random | pv | time ./bin/client notty sh -c "cat > /dev/null"

95.4MiB 0:00:00 [ 269MiB/s] [ <=>                                                                                  ]
./bin/client notty sh -c "cat > /dev/null"  0.32s user 0.31s system 31% cpu 2.019 total

Local sh directly

$ head -c 100000000 /dev/urandom > /tmp/random; cat /tmp/random | pv | time  sh -c "cat > /dev/null"

95.4MiB 0:00:00 [1.73GiB/s] [ <=>                                                                                  ]
sh -c "cat > /dev/null"  0.00s user 0.02s system 32% cpu 0.057 total