List nearby/discoverable bluetooth devices, including already paired, in Python, on Linux

Question

I'm trying to list all nearby/discoverable bluetooth devices, including those already paired, using Python on Linux.

I know how to list services for a device using its address, and can connect successfully:

services = bluetooth.find_service(address='...')

Reading the PyBluez docs I would expect any nearby device to show up if I don't specify any criteria:

"If no criteria are specified, then returns a list of all nearby services detected."

The "only" thing I need right now is to be able to list already paired devices, whether they are on, off, nearby or not. Much like the list I'm getting in All Settings --> Bluetooth in Ubuntu/Unity.

Btw, the following does not list already paired devices on my machine, even if they are on/nearby. Probably because they are not discoverable once paired:

import bluetooth
for d in bluetooth.discover_devices(flush_cache=True):
    print d

Any ideas ...?

Edit: I found and installed "bluez-tools".

bt-device --list

... gives me the information I need, i.e. addresses of added devices.

I've checked the C source, found out that this might not be as easy as I thought it would be.

Still don't know how to do this in Python ...

Edit: I think DBUS might be what I should be reading up on. Seems complicated enough. If anyone has got some code to share I would be really happy. :)

Answer 1

I managed to solve the problem myself. The following snippet lists addresses for all paired devices, on my default bluetooth adapter:

import dbus

bus = dbus.SystemBus()

manager = dbus.Interface(bus.get_object('org.bluez', '/'), 'org.bluez.Manager')

adapterPath = manager.DefaultAdapter()

adapter = dbus.Interface(bus.get_object('org.bluez', adapterPath), 'org.bluez.Adapter')

for devicePath in adapter.ListDevices():
    device = dbus.Interface(bus.get_object('org.bluez', devicePath),'org.bluez.Device')
    deviceProperties = device.GetProperties()
    print deviceProperties["Address"]

Answer 2

Since the adoption of the version 5 of the Bluetooth API most of the functions used in the @Micke solutions were dropped and the interaction with the bus take place throught the ObjectManager.GetManagedObjects [1]

import dbus


def proxyobj(bus, path, interface):
    """ commodity to apply an interface to a proxy object """
    obj = bus.get_object('org.bluez', path)
    return dbus.Interface(obj, interface)


def filter_by_interface(objects, interface_name):
    """ filters the objects based on their support
        for the specified interface """
    result = []
    for path in objects.keys():
        interfaces = objects[path]
        for interface in interfaces.keys():
            if interface == interface_name:
                result.append(path)
    return result


bus = dbus.SystemBus()

# we need a dbus object manager
manager = proxyobj(bus, "/", "org.freedesktop.DBus.ObjectManager")
objects = manager.GetManagedObjects()

# once we get the objects we have to pick the bluetooth devices.
# They support the org.bluez.Device1 interface
devices = filter_by_interface(objects, "org.bluez.Device1")

# now we are ready to get the informations we need
bt_devices = []
for device in devices:
    obj = proxyobj(bus, device, 'org.freedesktop.DBus.Properties')
    bt_devices.append({
        "name": str(obj.Get("org.bluez.Device1", "Name")),
        "addr": str(obj.Get("org.bluez.Device1", "Address"))
    })  

In the bt_device list there are dictionaries with the desired data: ie

for example

[{
    'name': 'BBC micro:bit [zigiz]', 
    'addr': 'E0:7C:62:5A:B1:8C'
 }, {
    'name': 'BBC micro:bit [putup]',
    'addr': 'FC:CC:69:48:5B:32'
}]

Reference: [1] http://www.bluez.org/bluez-5-api-introduction-and-porting-guide/