#4483 stub encoder server

xpra/scripts/main.py

@@ -216,6 +216,7 @@ def configure_logging(options, mode) -> None:
     if mode in (
             "seamless", "desktop", "monitor", "expand",
             "shadow", "shadow-screen",
+            "encoder",
             "recover",
             "attach", "listen", "proxy",
             "version", "info", "id",
@@ -453,6 +454,7 @@ def run_mode(script_file: str, cmdline, error_cb, options, args, full_mode: str,
     if mode in (
             "seamless", "desktop", "shadow", "shadow-screen", "expand",
             "upgrade", "upgrade-seamless", "upgrade-desktop",
+            "encoder",
     ) and not display_is_remote and options.daemon and use_systemd_run(options.systemd_run):
         # make sure we run via the same interpreter,
         # inject it into the command line if we have to:
@@ -522,6 +524,7 @@ def run_mode(script_file: str, cmdline, error_cb, options, args, full_mode: str,
     if mode in (
             "seamless", "desktop", "shadow", "shadow-screen", "expand",
             "recover",
+            "encoder",
     ) or mode.startswith("upgrade") or mode.startswith("request-"):
         options.encodings = validated_encodings(options.encodings)
     try:
@@ -615,6 +618,7 @@ def do_run_mode(script_file: str, cmdline, error_cb, options, args, full_mode: s
             "seamless", "desktop", "monitor", "expand", "shadow", "shadow-screen",
             "upgrade", "upgrade-seamless", "upgrade-desktop",
             "proxy",
+            "encoder",
     ):
         return run_server(script_file, cmdline, error_cb, options, args, full_mode, defaults)
     if mode in (
@@ -2302,6 +2306,7 @@ def run_server(script_file, cmdline, error_cb, options, args, full_mode: str, de
     if mode in (
             "seamless", "desktop", "monitor", "expand",
             "upgrade", "upgrade-seamless", "upgrade-desktop", "upgrade-monitor",
+            "encoder",
     ):
         if OSX or WIN32:
             raise InitException(f"{mode} is not supported on this platform")
@@ -2338,9 +2343,10 @@ def run_server(script_file, cmdline, error_cb, options, args, full_mode: str, de
             scaled_h = round(root_h / scaling_y)
             options.resize_display = f"{scaled_w}x{scaled_h}"
 
-    r = start_server_via_proxy(cmdline, error_cb, options, args, full_mode)
-    if isinstance(r, int):
-        return r
+    if mode != "encoder":
+        r = start_server_via_proxy(cmdline, error_cb, options, args, full_mode)
+        if isinstance(r, int):
+            return r
 
     try:
         from xpra import server

xpra/scripts/server.py

@@ -394,6 +394,11 @@ def make_expand_server(attrs: dict[str, str]):
     return ExpandServer(attrs)
 
 
+def make_encoder_server():
+    from xpra.server.encoder_server import EncoderServer
+    return EncoderServer()
+
+
 def verify_display(xvfb=None, display_name=None, shadowing=False, log_errors=True, timeout=None) -> bool:
     # check that we can access the X11 display:
     from xpra.log import Logger
@@ -629,6 +634,7 @@ def do_run_server(script_file: str, cmdline, error_cb, opts, extra_args, full_mo
         "seamless", "desktop", "monitor", "expand", "shadow", "shadow-screen",
         "upgrade", "upgrade-seamless", "upgrade-desktop", "upgrade-monitor",
         "proxy",
+        "encoder",
     )
     validate_encryption(opts)
     if opts.encoding == "help" or "help" in opts.encodings:
@@ -694,6 +700,7 @@ def _do_run_server(script_file: str, cmdline,
     upgrading = mode.startswith("upgrade")
     shadowing = mode.startswith("shadow")
     proxying = mode == "proxy"
+    encoder = mode == "encoder"
     use_display = parse_bool_or("use-display", opts.use_display)
     if shadowing or expanding:
         use_display = True
@@ -751,7 +758,7 @@ def _do_run_server(script_file: str, cmdline,
             if not shadowing and not upgrading and not use_display:
                 display_name_check(display_name)
         else:
-            if proxying:
+            if proxying or encoder:
                 # find a free display number:
                 dotxpra = DotXpra(opts.socket_dir, opts.socket_dirs)
                 all_displays = dotxpra.sockets()
@@ -796,7 +803,7 @@ def _do_run_server(script_file: str, cmdline,
             else:
                 warn(f"server for {display_name} is not exiting")
 
-    if not (shadowing or proxying or upgrading) and opts.exit_with_children and not has_child_arg:
+    if not (shadowing or proxying or upgrading or encoder) and opts.exit_with_children and not has_child_arg:
         error_cb("--exit-with-children specified without any children to spawn; exiting immediately")
 
     # Generate the script text now, because os.getcwd() will
@@ -864,7 +871,7 @@ def write_session_file(filename: str, contents) -> str:
             del e
 
     clobber = int(upgrading) * CLOBBER_UPGRADE | int(use_display or 0) * CLOBBER_USE_DISPLAY
-    start_vfb: bool = not (shadowing or proxying or clobber or expanding)
+    start_vfb: bool = not (shadowing or proxying or clobber or expanding or encoder)
     xauth_data: str = get_hex_uuid() if start_vfb else ""
 
     # if pam is present, try to create a new session:
@@ -929,7 +936,9 @@ def write_session_file(filename: str, contents) -> str:
         # with the value supplied by the user:
         protected_env["XDG_RUNTIME_DIR"] = xrd
 
-    xvfb_cmd = xvfb_command(opts.xvfb, opts.pixel_depth, opts.dpi)
+    xvfb_cmd: list[str] = []
+    if start_vfb:
+        xvfb_cmd = xvfb_command(opts.xvfb, opts.pixel_depth, opts.dpi)
 
     sanitize_env()
     if not shadowing:
@@ -1052,7 +1061,9 @@ def write_session_file(filename: str, contents) -> str:
             commands += list(getattr(opts, start_prop.replace("-", "_")))
         if not commands:
             opts.start.append("xpra desktop-greeter")
-    if POSIX and configure_imsettings_env(opts.input_method) == "ibus" and not (upgrading or shadowing or proxying):
+    if POSIX and not (
+            upgrading or shadowing or proxying or encoder
+    ) and configure_imsettings_env(opts.input_method) == "ibus":
         # start ibus-daemon unless already specified in 'start':
         if IBUS_DAEMON_COMMAND and not (any(x.find("ibus-daemon") >= 0 for x in opts.start) or any(
             x.find("ibus-daemon") >= 0 for x in opts.start_late)
@@ -1129,7 +1140,7 @@ def write_session_file(filename: str, contents) -> str:
             log(f"using XAUTHORITY file {xauthority!r}")
         os.environ["XAUTHORITY"] = xauthority
         # resolve use-display='auto':
-        if (use_display is None or upgrading) and not proxying:
+        if (use_display is None or upgrading) and not proxying and not encoder:
             # figure out if we have to start the vfb or not
             # bail out if we need a display that is not running
             if not display_name:
@@ -1171,7 +1182,7 @@ def write_session_file(filename: str, contents) -> str:
     if POSIX and not OSX:
         from xpra.server.util import has_uinput, UINPUT_UUID_LEN
         uinput_uuid = ""
-        use_uinput = not (shadowing or proxying) and opts.input_devices.lower() in ("uinput", "auto") and has_uinput()
+        use_uinput = not (shadowing or proxying or encoder) and opts.input_devices.lower() in ("uinput", "auto") and has_uinput()
         if start_vfb:
             progress(40, "starting a virtual display")
             from xpra.x11.vfb_util import start_Xvfb, parse_resolutions, xauth_add
@@ -1335,7 +1346,7 @@ def check_xvfb(timeout=0) -> bool:
         if dbus_env:
             os.environ.update(dbus_env)
 
-    if SSH_AGENT_DISPATCH and not (shadowing or proxying) and opts.ssh.lower() not in FALSE_OPTIONS:
+    if SSH_AGENT_DISPATCH and not (shadowing or proxying or encoder) and opts.ssh.lower() not in FALSE_OPTIONS:
         progress(50, "setup ssh agent forwarding")
         try:
             from xpra.net.ssh.agent import setup_ssh_auth_sock
@@ -1346,7 +1357,7 @@ def check_xvfb(timeout=0) -> bool:
             log.error("Error setting up ssh agent forwarding", exc_info=True)
             progress(50, f"error setting up ssh agent forwarding: {e}")
 
-    if not proxying:
+    if not (proxying or encoder):
         if POSIX and not OSX:
             no_gtk()
             if starting or starting_desktop or starting_monitor:
@@ -1389,7 +1400,7 @@ def init_local_sockets() -> None:
     if envbool("XPRA_ENFORCE_FEATURES", True):
         enforce_server_features()
 
-    if not (proxying or shadowing) and POSIX and not OSX:
+    if not (proxying or shadowing or encoder) and POSIX and not OSX:
         if not check_xvfb():
             return 1
         from xpra.x11.gtk.display_source import init_gdk_display_source
@@ -1422,6 +1433,8 @@ def _get_int(prop) -> int:
         app = make_proxy_server()
     elif expanding:
         app = make_expand_server(mode_attrs)
+    elif encoder:
+        app = make_encoder_server()
     else:
         if starting or upgrading_seamless:
             app = make_seamless_server(clobber)
@@ -1456,7 +1469,7 @@ def server_not_started(msg="server not started"):
         init_local_sockets()
         app.init_sockets(sockets)
         app.init_dbus(dbus_pid, dbus_env)
-        if not shadowing and not proxying and not expanding:
+        if not (shadowing or proxying or expanding or encoder):
             app.init_display_pid(xvfb_pid)
             app.save_pid()
         app.original_desktop_display = desktop_display

xpra/server/core.py

@@ -250,7 +250,7 @@ def __init__(self):
         self._default_packet_handlers: dict[str, Callable] = {}
 
     def get_server_mode(self) -> str:
-        return "core"
+        return self.session_type
 
     def init(self, opts) -> None:
         log("ServerCore.init(%s)", opts)

xpra/server/encoder_server.py

@@ -0,0 +1,66 @@
+# This file is part of Xpra.
+# Copyright (C) 2025 Antoine Martin <[email protected]>
+# Xpra is released under the terms of the GNU GPL v2, or, at your option, any
+# later version. See the file COPYING for details.
+
+from typing import Any
+from collections.abc import Callable
+
+from xpra.os_util import gi_import
+from xpra.gtk.signals import register_os_signals, register_SIGUSR_signals
+from xpra.server.mixins.encoding import EncodingServer
+from xpra.server.core import ServerCore
+from xpra.log import Logger
+
+GLib = gi_import("GLib")
+
+log = Logger("server")
+
+
+class EncoderServer(ServerCore, EncodingServer):
+
+    def __init__(self):
+        log("EncoderServer.__init__()")
+        super().__init__()
+        self.session_type = "encoder"
+        self.loop = GLib.MainLoop()
+
+    def init(self, opts):
+        opts.start_new_commands = False
+        ServerCore.init(self, opts)
+        EncodingServer.init(self, opts)
+
+    def threaded_init(self) -> None:
+        EncoderServer.threaded_setup(self)
+
+    def install_signal_handlers(self, callback: Callable[[int], None]) -> None:
+        sstr = self.get_server_mode() + " server"
+        register_os_signals(callback, sstr)
+        register_SIGUSR_signals(sstr)
+
+    def do_run(self) -> None:
+        log("do_run() calling %s", self.loop.run)
+        self.loop.run()
+        log("do_run() end of %()", self.loop.run)
+
+    def do_quit(self) -> None:
+        log("do_quit: calling loop.quit()")
+        self.loop.quit()
+        # from now on, we can't rely on the main loop:
+        from xpra.util.system import register_SIGUSR_signals
+        register_SIGUSR_signals()
+
+    def get_info(self, proto) -> dict[str, Any]:
+        info = ServerCore.get_info(self, proto)
+        info.update(EncodingServer.get_info(self, proto))
+        return info
+
+    def cleanup(self):
+        EncodingServer.cleanup(self)
+        ServerCore.cleanup(self)
+
+    def make_hello(self, source) -> dict[str, Any]:
+        capabilities = super().make_hello(source)
+        if "features" in source.wants:
+            capabilities.update(EncoderServer.get_server_features(source))
+        return capabilities