qubes-notification-daemon: WIP refactor notification daemon

Adapated from previous work:
- https://gist.github.com/v6ak/6ef6768103587bc273fb
- https://github.com/nastaziya/dbus-notify/

QubesOS/qubes-issues#889

Makefile

@@ -121,7 +121,7 @@ install-init:
 	install -d $(DESTDIR)$(LIBDIR)/qubes/init
 	# FIXME: do a source code move vm-systemd/*.sh to init/
 	# since those scripts are shared between sysvinit and systemd.
-	install -m 0755 init/*.sh vm-systemd/*.sh $(DESTDIR)$(LIBDIR)/qubes/init/
+	install -m 0755 init/*.sh vm-systemd/*.sh vm-systemd/*.py $(DESTDIR)$(LIBDIR)/qubes/init/
 	install -m 0644 init/functions $(DESTDIR)$(LIBDIR)/qubes/init/
 
 # Systemd service files
@@ -136,6 +136,8 @@ install-systemd: install-init
 	install -m 0644 vm-systemd/75-qubes-vm.preset $(DESTDIR)$(SYSLIBDIR)/systemd/system-preset/
 	install -m 0644 vm-systemd/qubes-core.conf $(DESTDIR)$(SYSLIBDIR)/modules-load.d/
 
+	mv $(DESTDIR)$(SYSLIBDIR)/systemd/system/org.freedesktop.qubes.Notifications.service $(DESTDIR)/usr/share/dbus-1/services/
+
 install-sysvinit: install-init
 	install -d $(DESTDIR)/etc/init.d
 	install vm-init.d/qubes-sysinit $(DESTDIR)/etc/init.d/

rpm_spec/core-agent.spec.in

@@ -666,6 +666,7 @@ rm -f %{name}-%{version}
 /usr/lib/qubes/init/resize-rootfs-if-needed.sh
 /usr/lib/qubes/init/setup-rw.sh
 /usr/lib/qubes/init/setup-rwdev.sh
+/usr/lib/qubes/init/qubes-notifyd.py
 %dir /usr/lib/qubes-bind-dirs.d
 /usr/lib/qubes-bind-dirs.d/30_cron.conf
 /usr/share/applications/qubes-run-terminal.desktop
@@ -851,6 +852,8 @@ The Qubes core startup configuration for SystemD init.
 /lib/systemd/system/qubes-sync-time.timer
 /lib/systemd/system/qubes-updates-proxy-forwarder@.service
 /lib/systemd/system/qubes-updates-proxy-forwarder.socket
+/lib/systemd/system/qubes-notifyd.service
+/usr/share/dbus-1/services/org.freedesktop.qubes.Notifications.service
 /lib/systemd/system-preset/%qubes_preset_file
 /lib/modules-load.d/qubes-core.conf
 /lib/systemd/system/boot.automount.d/30_qubes.conf

vm-systemd/org.freedesktop.qubes.Notifications.service

@@ -0,0 +1,4 @@
+[D-BUS Service]
+Name=org.freedesktop.Notifications
+Exec=/usr/lib/qubes/init/qubes-notifyd.py
+SystemdService=qubes-notifyd.service

vm-systemd/qubes-notifyd.py

@@ -0,0 +1,54 @@
+#!/usr/bin/env python3
+
+import dbus.service
+import dbus.mainloop.glib
+from gi.repository import GLib
+import subprocess
+import dbus
+
+
+class NotificationFetcher(dbus.service.Object):
+    _id = 0
+
+    @dbus.service.method("org.freedesktop.Notifications",
+                         in_signature='susssasa{ss}i',
+                         out_signature='u')
+    def Notify(self, app_name, notification_id, app_icon,
+               summary, body, actions, hints, expire_timeout):
+        if not notification_id:
+            self._id += 1
+            notification_id = self._id
+        # send data notification @default
+        subprocess.call(
+            ["/usr/lib/qubes/qrexec-client-vm", "",
+             "qubes.TrayNotification",
+             "/usr/bin/printf", "{}\n{}\n{}\n".format(app_name, summary, body)])
+        return notification_id
+
+    @dbus.service.method("org.freedesktop.Notifications", in_signature='',
+                         out_signature='as')
+    def GetCapabilities(self):
+        return "body"
+
+    @dbus.service.signal('org.freedesktop.Notifications', signature='uu')
+    def NotificationClosed(self, id_in, reason_in):
+        pass
+
+    @dbus.service.method("org.freedesktop.Notifications", in_signature='u',
+                         out_signature='')
+    def CloseNotification(self, id):
+        pass
+
+    @dbus.service.method("org.freedesktop.Notifications", in_signature='',
+                         out_signature='ssss')
+    def GetServerInformation(self):
+        return "qubes.TrayNotification", "https://www.qubes-os.org/", "0.0", "1"
+
+
+if __name__ == '__main__':
+    dbus.mainloop.glib.DBusGMainLoop(set_as_default=True)
+    session_bus = dbus.SessionBus()
+    name = dbus.service.BusName("org.freedesktop.Notifications", session_bus)
+    NotificationFetcher(session_bus, '/org/freedesktop/Notifications')
+    loop = GLib.MainLoop()
+    loop.run()

vm-systemd/qubes-notifyd.service

@@ -0,0 +1,8 @@
+[Unit]
+Description=Qubes notifications service
+
+[Service]
+Type=dbus
+BusName=org.freedesktop.Notifications
+ExecStart=/usr/lib/qubes/init/qubes-notifyd.py
+