#
# Identification of DBus objects, interfaces and services
#
# Copyright (C) 2019 Red Hat, Inc. All rights reserved.
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
# USA
#
from dasbus.namespace import get_dbus_path, get_dbus_name
__all__ = [
'DBusInterfaceIdentifier',
'DBusObjectIdentifier',
'DBusServiceIdentifier'
]
class DBusBaseIdentifier(object):
"""A base identifier."""
def __init__(self, namespace, basename=None):
"""Create an identifier.
:param namespace: a sequence of strings
:param basename: a string with the base name or None
"""
if basename:
namespace = (*namespace, basename)
self._namespace = namespace
self._name = get_dbus_name(*namespace)
self._path = get_dbus_path(*namespace)
@property
def namespace(self):
"""DBus namespace of this object."""
return self._namespace
def __str__(self):
"""Return the string representation."""
return self._name
[docs]class DBusInterfaceIdentifier(DBusBaseIdentifier):
"""Identifier of a DBus interface."""
def __init__(self, namespace, basename=None, interface_version=None):
"""Describe a DBus interface.
:param namespace: a sequence of strings
:param basename: a string with the base name or None
:param interface_version: a version of the interface
"""
super().__init__(namespace, basename=basename)
self._interface_version = interface_version
def _version_to_string(self, version):
"""Convert version to a string.
:param version: a number or None
:return: a string
"""
if version is None:
return ""
return str(version)
@property
def interface_name(self):
"""Full name of the DBus interface."""
return self._name + self._version_to_string(self._interface_version)
def __str__(self):
"""Return the string representation."""
return self.interface_name
[docs]class DBusObjectIdentifier(DBusInterfaceIdentifier):
"""Identifier of a DBus object."""
def __init__(self, namespace, basename=None, interface_version=None,
object_version=None):
"""Describe a DBus object.
:param namespace: a sequence of strings
:param basename: a string with the base name or None
:param interface_version: a version of the DBus interface
:param object_version: a version of the DBus object
"""
super().__init__(namespace, basename=basename,
interface_version=interface_version)
self._object_version = object_version
@property
def object_path(self):
"""Full path of the DBus object."""
return self._path + self._version_to_string(self._object_version)
def __str__(self):
"""Return the string representation."""
return self.object_path
[docs]class DBusServiceIdentifier(DBusObjectIdentifier):
"""Identifier of a DBus service."""
def __init__(self, message_bus, namespace, basename=None,
interface_version=None, object_version=None,
service_version=None):
"""Describe a DBus service.
:param message_bus: a message bus
:param namespace: a sequence of strings
:param basename: a string with the base name or None
:param interface_version: a version of the DBus interface
:param object_version: a version of the DBus object
:param service_version: a version of the DBus service
"""
super().__init__(namespace, basename=basename,
interface_version=interface_version,
object_version=object_version)
self._service_version = service_version
self._message_bus = message_bus
@property
def message_bus(self):
"""Message bus of the DBus service.
:return: a message bus
:rtype: an instance of the MessageBus class
"""
return self._message_bus
@property
def service_name(self):
"""Full name of a DBus service."""
return self._name + self._version_to_string(self._service_version)
def __str__(self):
"""Return the string representation."""
return self.service_name
def _choose_object_path(self, object_id):
"""Choose an object path."""
if object_id is None:
return self.object_path
if isinstance(object_id, DBusObjectIdentifier):
return object_id.object_path
return object_id
def _choose_interface_name(self, interface_id):
"""Choose an interface name."""
if interface_id is None:
return None
if isinstance(interface_id, DBusInterfaceIdentifier):
return interface_id.interface_name
return interface_id
[docs] def get_proxy(self, object_path=None, interface_name=None,
**bus_arguments):
"""Returns a proxy of the DBus object.
If no object path is specified, we will use the object path
of this DBus service.
If no interface name is specified, we will use none and create
a proxy from all interfaces of the DBus object.
:param object_path: an object identifier or a DBus path or None
:param interface_name: an interface identifier or a DBus name or None
:param bus_arguments: additional arguments for the message bus
:return: a proxy object
"""
object_path = self._choose_object_path(object_path)
interface_name = self._choose_interface_name(interface_name)
return self._message_bus.get_proxy(
self.service_name,
object_path,
interface_name,
**bus_arguments
)