DBus接口属性

Question

如何获取可用的DBus接口属性列表？

我正在编写一个跟踪特定类型的USB设备连接的脚本.一种区分要跟踪的连接与所有usb连接的方法我想是检查DBus在usb连接上发送的信号接口的属性.我想得到所有这些属性的列表来选择相关的.

我的代码是:

    import sys
    import dbus
    from dbus.mainloop.glib import DBusGMainLoop
    import gobject

    def deviceAdded(udi):
        device = bus.get_object("org.freedesktop.Hal", udi)
        device_if = dbus.Interface(device, 'org.freedesktop.Hal.Device')
        if device_if.GetPropertyString('info.subsystem') == 'usb_device':
            #
            # Properties can be accesed like this:
            # vendor_id = device_if.GetPropertyInteger('usb_device.vendor_id')
            # 
            # how to get the list of all properties?
            #
            # do something

    def deviceRemoved(udi):
        # do something
        pass

    if __name__ == "__main__":
    DBusGMainLoop(set_as_default=True)
    bus = dbus.SystemBus()

    bus.add_signal_receiver( 
        deviceAdded,
        'DeviceAdded',
        'org.freedesktop.Hal.Manager',
        'org.freedesktop.Hal',
        '/org/freedesktop/Hal/Manager')

    bus.add_signal_receiver( 
        deviceRemoved,
        'DeviceRemoved',
        'org.freedesktop.Hal.Manager',
        'org.freedesktop.Hal',
        '/org/freedesktop/Hal/Manager')

    loop = gobject.MainLoop()

    try:
        loop.run()
    except KeyboardInterrupt:
        print "usb-device-tracker: keyboad interrupt received, shutting down"
        loop.quit()
        sys.exit(0)

Answer 1

首先，检查 hal 文档和来源，它们永远是你的朋友。

import dbus
bus = dbus.SystemBus()
dev = bus.get_object("org.freedesktop.Hal", u'/org/freedesktop/Hal/devices/computer_logicaldev_input')
iface = dbus.Interface(dev, 'org.freedesktop.Hal.Device')
props = iface.GetAllProperties()
print "\n".join(("%s: %s" % (k, props[k]) for k in props))

作为最后的手段，您始终可以使用“lshal”命令找到您感兴趣的属性。