dasbus 1.7

DBus library in Python 3

dasbus

This DBus library is written in Python 3, based on GLib and inspired by pydbus. Find out more in the documentation.

The code used to be part of the Anaconda Installer project. It was based on the pydbus library, but we replaced it with our own solution because its upstream development stalled. The dasbus library is a result of this effort.

Requirements

• Python 3.6+
• PyGObject 3

You can install PyGObject provided by your operating system or use PyPI. The system package is usually called python3-gi, python3-gobject or pygobject3. See the instructions for your platform (only for PyGObject, you don't need cairo or GTK).

The library is known to work with Python 3.8, PyGObject 3.34 and GLib 2.63, but these are not the required minimal versions.

Installation

Install the package from PyPI or install the package provided by your operating system if available.

Install from PyPI

Follow the instructions above to install the requirements before you install dasbus with pip. The required dependencies has to be installed manually in this case.

pip3 install dasbus

Install the system package

Follow the instructions for your operating system to install the python-dasbus package. The required dependencies should be installed automatically by the system package manager.

• Arch Linux
• Debian / Ubuntu
• Fedora / CentOS / RHEL
• openSUSE

Examples

Show the current hostname.

from dasbus.connection import SystemMessageBus
bus = SystemMessageBus()

proxy = bus.get_proxy(
    "org.freedesktop.hostname1",
    "/org/freedesktop/hostname1"
)

print(proxy.Hostname)

Send a notification to the notification server.

from dasbus.connection import SessionMessageBus
bus = SessionMessageBus()

proxy = bus.get_proxy(
    "org.freedesktop.Notifications",
    "/org/freedesktop/Notifications"
)

id = proxy.Notify(
    "", 0, "face-smile", "Hello World!",
    "This notification can be ignored.",
    [], {}, 0
)

print("The notification {} was sent.".format(id))

Handle a closed notification.

from dasbus.loop import EventLoop
loop = EventLoop()

from dasbus.connection import SessionMessageBus
bus = SessionMessageBus()

proxy = bus.get_proxy(
    "org.freedesktop.Notifications",
    "/org/freedesktop/Notifications"
)

def callback(id, reason):
    print("The notification {} was closed.".format(id))

proxy.NotificationClosed.connect(callback)
loop.run()

Asynchronously fetch a list of network devices.

from dasbus.loop import EventLoop
loop = EventLoop()

from dasbus.connection import SystemMessageBus
bus = SystemMessageBus()

proxy = bus.get_proxy(
    "org.freedesktop.NetworkManager",
    "/org/freedesktop/NetworkManager"
)

def callback(call):
    print(call())

proxy.GetDevices(callback=callback)
loop.run()

Inhibit the system suspend and hibernation.

import os
from dasbus.connection import SystemMessageBus
from dasbus.unix import GLibClientUnix
bus = SystemMessageBus()

proxy = bus.get_proxy(
    "org.freedesktop.login1",
    "/org/freedesktop/login1",
    client=GLibClientUnix
)

fd = proxy.Inhibit(
    "sleep", "my-example", "Running an example", "block"
)

proxy.ListInhibitors()
os.close(fd)

Define the org.example.HelloWorld service.

class HelloWorld(object):
    __dbus_xml__ = """
    <node>
        <interface name="org.example.HelloWorld">
            <method name="Hello">
                <arg direction="in" name="name" type="s" />
                <arg direction="out" name="return" type="s" />
            </method>
        </interface>
    </node>
    """

    def Hello(self, name):
        return "Hello {}!".format(name)

Define the org.example.HelloWorld service with an automatically generated XML specification.

from dasbus.server.interface import dbus_interface
from dasbus.typing import Str

@dbus_interface("org.example.HelloWorld")
class HelloWorld(object):

    def Hello(self, name: Str) -> Str:
        return "Hello {}!".format(name)

print(HelloWorld.__dbus_xml__)

Publish the org.example.HelloWorld service on the session message bus.

from dasbus.connection import SessionMessageBus
bus = SessionMessageBus()
bus.publish_object("/org/example/HelloWorld", HelloWorld())
bus.register_service("org.example.HelloWorld")

from dasbus.loop import EventLoop
loop = EventLoop()
loop.run()

See more examples in the documentation.

Inspiration

Look at the complete examples or DBus services of the Anaconda Installer for more inspiration.