Stream Wayland desktop over network with Pipewire, GStreamer and MJPEG

client.sh

#!/bin/bash

gst-launch-1.0 tcpclientsrc host=localhost port=5000 ! multipartdemux ! jpegdec ! videoconvert ! autovideosink

server.py

#!/usr/bin/python3

# See https://gitlab.gnome.org/-/snippets/19

import re
import signal
import dbus
from gi.repository import GLib, GObject, Gst
from dbus.mainloop.glib import DBusGMainLoop

DBusGMainLoop(set_as_default=True)
Gst.init(None)

loop = GLib.MainLoop()
bus = dbus.SessionBus()
request_iface = 'org.freedesktop.portal.Request'
screen_cast_iface = 'org.freedesktop.portal.ScreenCast'
pipeline = None

request_token_counter = 0
session_token_counter = 0
sender_name = re.sub(r'\.', '_', bus.get_unique_name()[1:])

def new_request_path():
    global request_token_counter
    request_token_counter += 1
    token = f'u{request_token_counter}'
    return f'/org/freedesktop/portal/desktop/request/{sender_name}/{token}', token

def new_session_path():
    global session_token_counter
    session_token_counter += 1
    token = f'u{session_token_counter}'
    return f'/org/freedesktop/portal/desktop/session/{sender_name}/{token}', token

def screen_cast_call(method, callback, *args, options={}):
    request_path, request_token = new_request_path()
    bus.add_signal_receiver(callback, 'Response', request_iface, 'org.freedesktop.portal.Desktop', request_path)
    options['handle_token'] = request_token
    method(*args, options, dbus_interface=screen_cast_iface)

portal = bus.get_object('org.freedesktop.portal.Desktop', '/org/freedesktop/portal/desktop')

screen_cast_call(portal.CreateSession, 
    lambda response, results: (
        print(f"Failed to create session: {response}") if response != 0 else (
            globals().update({'session': results['session_handle']}),
            print(f"session {results['session_handle']} created"),
            screen_cast_call(portal.SelectSources, 
                lambda response, results: (
                    print(f"Failed to select sources: {response}") if response != 0 else (
                        print("sources selected"),
                        screen_cast_call(portal.Start, 
                            lambda response, results: (
                                print(f"Failed to start: {response}") if response != 0 else (
                                    print("streams:"),
                                    [(
                                        print(f"stream {node_id}"),
                                        (pipeline := Gst.parse_launch(f'pipewiresrc fd={portal.OpenPipeWireRemote(session, dbus.Dictionary(signature="sv"), dbus_interface=screen_cast_iface).take()} path={node_id} ! videorate ! video/x-raw,framerate=60/1 ! videoconvert ! clockoverlay shaded-background=true font-desc="Sans 38" ! queue ! jpegenc ! multipartmux ! queue ! tcpserversink host=0.0.0.0 port=5000')).set_state(Gst.State.PLAYING),
                                        pipeline.get_bus().connect('message', 
                                            lambda bus, message: (
                                                (pipeline.set_state(Gst.State.NULL), loop.quit()) if message.type in (Gst.MessageType.EOS, Gst.MessageType.ERROR) else None
                                            )
                                        )
                                    ) for node_id, _ in results['streams']]
                                )
                            ),
                            session, ''
                        )
                    )
                ),
                session, options={'multiple': False, 'types': dbus.UInt32(1 | 2)}
            )
        )
    ),
    options={'session_handle_token': new_session_path()[1]}
)

try:
    loop.run()
except KeyboardInterrupt:
    pipeline.set_state(Gst.State.NULL) if pipeline else None
    loop.quit()